Mercurial Hosting > luan
annotate website/src/manual.html.luan @ 386:db23f654f87d
make all of website use luan
| author | Franklin Schmidt <fschmidt@gmail.com> |
|---|---|
| date | Thu, 23 Apr 2015 18:09:12 -0600 |
| parents | website/src/manual.html@8557581740db |
| children | 23d075ce1e48 |
| rev | line source |
|---|---|
|
386
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
1 local Io = require "luan:Io" |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
2 local Html = require "luan:Html" |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
3 local Http = require "luan:web/Http" |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
4 |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
5 |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
6 function service() |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
7 Io.stdout = Http.response.text_writer() |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
8 Html.simply_html_page{ |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
9 head = function() %> |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
10 <title>Luan Reference Manual</title> |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
11 <% end; |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
12 body = function() %> |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
13 |
| 372 | 14 <div container> |
| 15 <div><small><a href="/">Luan</a></small></div> | |
| 16 | |
| 17 <h1>Luan Reference Manual</h1> | |
| 18 | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
19 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
20 <small> |
| 372 | 21 Original copyright © 2015 Lua.org, PUC-Rio. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
22 Freely available under the terms of the |
| 372 | 23 <a href="http://www.lua.org/license.html">Lua license</a>. |
| 24 Modified for Luan. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
25 </small> |
| 372 | 26 </p> |
| 27 | |
| 28 <hr/> | |
| 29 | |
| 30 <h2>Contents</h2> | |
| 31 | |
| 32 <div margin-bottom="1em"><a href="#intro">Introduction</a></div> | |
| 33 | |
| 373 | 34 <div margin-bottom="1em"> |
| 35 <a href="#basic">Basic Concepts</a> | |
| 36 <ul> | |
| 37 <li><a href="#types">Values and Types</a></li> | |
| 38 <li><a href="#env">Environments</a></li> | |
| 39 <li><a href="#error">Error Handling</a></li> | |
| 40 <li><a href="#meta">Metatables and Metamethods</a></li> | |
| 380 | 41 <li><a href="#gc">Garbage Collection</a></li> |
| 42 </ul> | |
| 43 </div> | |
| 44 | |
| 45 <div margin-bottom="1em"> | |
| 46 <a href="#lang">The Language</a> | |
| 47 <ul> | |
| 48 <li><a href="#lex">Lexical Conventions</a></li> | |
| 49 <li><a href="#vars">Variables</a></li> | |
| 373 | 50 </ul> |
| 51 </div> | |
| 52 | |
| 372 | 53 <hr/> |
| 54 | |
| 373 | 55 |
| 372 | 56 <h2 margin-top="1em"><a name="intro">Introduction</a></h2> |
| 57 | |
| 58 <p>Luan is a high level programming language based on <a href="http://www.lua.org">Lua</a>. A great strength of Lua is its simplicity and Luan takes this even further, being even simpler than Lua. The goal is to provide a simple programming language for the casual programmer with as few concepts as possible so that one can quickly learn the language and then easily understand any code written in Luan.</p> | |
| 59 | |
| 60 <p>Luan is implemented in Java and is tightly coupled with Java. So it makes a great scripting language for Java programmers.</p> | |
| 61 | |
| 62 <p>Unlike Lua which is meant to be embedded, Luan is meant to be a full scripting language. This done not by adding feature to Luan, but rather by providing a complete set of libraries.</p> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
63 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
64 |
| 373 | 65 <h2 margin-top="1em"><a name="basic">Basic Concepts</a></h2> |
| 66 | |
| 67 <p>This section describes the basic concepts of the language.</p> | |
| 68 | |
| 69 <h3 margin-top="1em"><a name="types">Values and Types</a></h3> | |
| 70 | |
| 71 <p> | |
| 72 Luan is a <i>dynamically typed language</i>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
73 This means that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
74 variables do not have types; only values do. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
75 There are no type definitions in the language. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
76 All values carry their own type. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
77 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
78 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
79 <p> |
| 373 | 80 All values in Luan are <i>first-class values</i>. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
81 This means that all values can be stored in variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
82 passed as arguments to other functions, and returned as results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
83 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
84 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
85 <p> |
| 373 | 86 There are eight basic types in Luan: |
| 87 <i>nil</i>, <i>boolean</i>, <i>number</i>, | |
| 88 <i>string</i>, <i>binary</i>, <i>function</i>, <i>userdata</i>, | |
| 89 and <i>table</i>. | |
| 90 <i>Nil</i> is the type of the value <b>nil</b>, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
91 whose main property is to be different from any other value; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
92 it usually represents the absence of a useful value. |
| 373 | 93 <i>Nil</i> is implemented as the Java value <i>null</i>. |
| 94 <i>Boolean</i> is the type of the values <b>false</b> and <b>true</b>. | |
| 95 <i>Boolean</i> is implemented as the Java class <i>Boolean</i>. | |
| 96 <i>Number</i> represents both | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
97 integer numbers and real (floating-point) numbers. |
| 373 | 98 <i>Number</i> is implemented as the Java class <i>Number</i>. Any Java subclass of <i>Number</i> is allowed and this is invisible to the Luan user. Operations on numbers follow the same rules of |
| 99 the underlying Java implementation. | |
| 100 | |
| 101 <i>String</i> is implemented as the Java class <i>String</i>. | |
| 102 <i>Binary</i> is implemented as the Java type <i>byte[]</i>. | |
| 103 | |
| 104 | |
| 105 <p> | |
| 106 Luan can call (and manipulate) functions written in Luan and | |
| 107 functions written in Java (see <a href="#3.4.10">§3.4.10</a>). | |
| 108 Both are represented by the type <i>function</i>. | |
| 109 | |
| 110 | |
| 111 <p> | |
| 112 The type <i>userdata</i> is provided to allow arbitrary Java objects to | |
| 113 be stored in Luan variables. | |
| 114 A userdata value is a Java object that isn't one of the standard Luan types. | |
| 115 Userdata has no predefined operations in Luan, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
116 except assignment and identity test. |
| 373 | 117 Userdata is useful then Java access is enabled in Luan |
| 118 | |
| 119 | |
| 120 | |
| 121 <p> | |
| 122 The type <i>table</i> implements associative arrays, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
123 that is, arrays that can be indexed not only with numbers, |
| 373 | 124 but with any Luan value except <b>nil</b>. |
| 125 Tables can be <i>heterogeneous</i>; | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
126 that is, they can contain values of all types (except <b>nil</b>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
127 Any key with value <b>nil</b> is not considered part of the table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
128 Conversely, any key that is not part of a table has |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
129 an associated value <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
130 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
131 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
132 <p> |
| 373 | 133 Tables are the sole data-structuring mechanism in Luan; |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
134 they can be used to represent ordinary arrays, sequences, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
135 symbol tables, sets, records, graphs, trees, etc. |
| 373 | 136 To represent records, Luan uses the field name as an index. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
137 The language supports this representation by |
| 373 | 138 providing <tt>a.name</tt> as syntactic sugar for <tt>a["name"]</tt>. |
| 139 There are several convenient ways to create tables in Luan | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
140 (see <a href="#3.4.9">§3.4.9</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
143 <p> |
| 373 | 144 We use the term <i>sequence</i> to denote a table where |
| 145 the set of all positive numeric keys is equal to {1..<i>n</i>} | |
| 146 for some non-negative integer <i>n</i>, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
147 which is called the length of the sequence (see <a href="#3.4.7">§3.4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
148 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
149 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
150 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
151 Like indices, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
152 the values of table fields can be of any type. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
153 In particular, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
154 because functions are first-class values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
155 table fields can contain functions. |
| 373 | 156 Thus tables can also carry <i>methods</i> (see <a href="#3.4.11">§3.4.11</a>). |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
157 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
158 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
159 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
160 The indexing of tables follows |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
161 the definition of raw equality in the language. |
| 373 | 162 The expressions <tt>a[i]</tt> and <tt>a[j]</tt> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
163 denote the same table element |
| 373 | 164 if and only if <tt>i</tt> and <tt>j</tt> are raw equal |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
165 (that is, equal without metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
166 In particular, floats with integral values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
167 are equal to their respective integers |
| 373 | 168 (e.g., <tt>1.0 == 1</tt>). |
| 169 | |
| 170 | |
| 171 <p> | |
| 172 Luan values are <i>objects</i>: | |
| 173 variables do not actually <i>contain</i> values, | |
| 174 only <i>references</i> to them. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
175 Assignment, parameter passing, and function returns |
| 373 | 176 always manipulate references to values; |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
177 these operations do not imply any kind of copy. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
178 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
179 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
180 <p> |
| 373 | 181 The library function <a href="#pdf-type"><tt>Luan.type</tt></a> returns a string describing the type |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
182 of a given value (see <a href="#6.1">§6.1</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
183 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
185 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
186 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
187 |
| 373 | 188 <h3 margin-top="1em"><a name="env">Environments</a></h3> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
190 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
191 As will be discussed in <a href="#3.2">§3.2</a> and <a href="#3.3.3">§3.3.3</a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
192 any reference to a free name |
| 373 | 193 (that is, a name not bound to any declaration) <tt>var</tt> |
| 194 is syntactically translated to <tt>_ENV.var</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
195 Moreover, every chunk is compiled in the scope of |
| 373 | 196 an external local variable named <tt>_ENV</tt> (see <a href="#3.3.2">§3.3.2</a>), |
| 197 so <tt>_ENV</tt> itself is never a free name in a chunk. | |
| 198 | |
| 199 | |
| 200 <p> | |
| 201 Despite the existence of this external <tt>_ENV</tt> variable and | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
202 the translation of free names, |
| 373 | 203 <tt>_ENV</tt> is a completely regular name. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
204 In particular, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
205 you can define new variables and parameters with that name. |
| 373 | 206 Each reference to a free name uses the <tt>_ENV</tt> that is |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
207 visible at that point in the program, |
| 373 | 208 following the usual visibility rules of Luan (see <a href="#3.5">§3.5</a>). |
| 209 | |
| 210 | |
| 211 <p> | |
| 212 Any table used as the value of <tt>_ENV</tt> is called an <i>environment</i>. | |
| 213 | |
| 214 | |
| 215 <p> | |
| 216 When Luan loads a chunk, | |
| 217 the default value for its <tt>_ENV</tt> is an empty table. | |
| 218 | |
| 219 <p> | |
| 220 Luan also provides all chunks with two other local values: <tt>require</tt> and <tt>java</tt>. These are functions used to load and access libraries and other modules. | |
| 221 | |
| 222 | |
| 223 | |
| 224 | |
| 225 <h3 margin-top="1em"><a name="error">Error Handling</a></h3> | |
| 226 | |
| 227 <p> | |
| 228 Luan code can explicitly generate an error by calling the | |
| 229 <a href="#pdf-error"><tt>error</tt></a> function. | |
| 230 If you need to catch errors in Luan, | |
| 231 you can use <a href="#pdf-pcall"><tt>pcall</tt></a> or <a href="#pdf-xpcall"><tt>try</tt></a> | |
| 232 to call a given function in <i>protected mode</i>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
233 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
234 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
235 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
236 Whenever there is an error, |
| 373 | 237 an <i>error object</i> (also called an <i>error message</i>) |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
238 is propagated with information about the error. |
| 373 | 239 Luan itself only generates errors whose error object is a string, |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
240 but programs may generate errors with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
241 any value as the error object. |
| 373 | 242 It is up to the Luan program or its host to handle such error objects. |
| 243 | |
| 244 | |
| 245 | |
| 246 | |
| 247 | |
| 248 <h3 margin-top="1em"><a name="meta">Metatables and Metamethods</a></h3> | |
| 249 | |
| 250 <p> | |
| 251 Every table in Luan can have a <i>metatable</i>. | |
| 252 This <i>metatable</i> is an ordinary Luan table | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
253 that defines the behavior of the original value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
254 under certain special operations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
255 You can change several aspects of the behavior |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
256 of operations over a value by setting specific fields in its metatable. |
| 373 | 257 For instance, when a table is the operand of an addition, |
| 258 Luan checks for a function in the field "<tt>__add</tt>" of the table's metatable. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
259 If it finds one, |
| 373 | 260 Luan calls this function to perform the addition. |
| 261 | |
| 262 | |
| 263 <p> | |
| 264 The keys in a metatable are derived from the <i>event</i> names; | |
| 265 the corresponding values are called <ii>metamethods</i>. | |
| 266 In the previous example, the event is <tt>"add"</tt> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
267 and the metamethod is the function that performs the addition. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
268 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
269 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
270 <p> |
| 373 | 271 You can query the metatable of any table |
| 272 using the <a href="#pdf-getmetatable"><tt>get_metatable</tt></a> function. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
273 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
275 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
276 You can replace the metatable of tables |
| 373 | 277 using the <a href="#pdf-setmetatable"><tt>set_metatable</tt></a> function. |
| 278 | |
| 279 | |
| 280 <p> | |
| 281 A metatable controls how a table behaves in | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
282 arithmetic operations, bitwise operations, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
283 order comparisons, concatenation, length operation, calls, and indexing. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
284 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
285 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
286 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
287 A detailed list of events controlled by metatables is given next. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
288 Each operation is identified by its corresponding event name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
289 The key for each event is a string with its name prefixed by |
| 373 | 290 two underscores, '<tt>__</tt>'; |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
291 for instance, the key for operation "add" is the |
| 373 | 292 string "<tt>__add</tt>". |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
293 Note that queries for metamethods are always raw; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
294 the access to a metamethod does not invoke other metamethods. |
| 373 | 295 You can emulate how Luan queries a metamethod for an object <tt>obj</tt> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
296 with the following code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
297 |
| 382 | 298 <p><tt><pre> |
| 373 | 299 raw_get(get_metatable(obj) or {}, "__" .. event_name) |
| 382 | 300 </pre></tt></p> |
| 373 | 301 |
| 302 <p> | |
| 303 Here are the events: | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
304 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
305 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
306 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
307 <li><b>"add": </b> |
| 373 | 308 the <tt>+</tt> operation. |
| 309 | |
| 310 If any operand for an addition is a table, | |
| 311 Luan will try to call a metamethod. | |
| 312 First, Luan will check the first operand (even if it is valid). | |
| 313 If that operand does not define a metamethod for the "<tt>__add</tt>" event, | |
| 314 then Luan will check the second operand. | |
| 315 If Luan can find a metamethod, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
316 it calls the metamethod with the two operands as arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
317 and the result of the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
318 (adjusted to one value) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
319 is the result of the operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
320 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
321 it raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
322 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
323 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
324 <li><b>"sub": </b> |
| 373 | 325 the <tt>-</tt> operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
326 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
327 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
328 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
329 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
330 <li><b>"mul": </b> |
| 373 | 331 the <tt>*</tt> operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
332 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
333 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
334 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
335 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
336 <li><b>"div": </b> |
| 373 | 337 the <tt>/</tt> operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
338 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
339 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
340 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
341 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
342 <li><b>"mod": </b> |
| 373 | 343 the <tt>%</tt> operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
344 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
345 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
346 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
347 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
348 <li><b>"pow": </b> |
| 373 | 349 the <tt>^</tt> (exponentiation) operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
351 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
352 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
353 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
354 <li><b>"unm": </b> |
| 373 | 355 the <tt>-</tt> (unary minus) operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
357 Behavior similar to the "add" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
358 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
359 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
360 <li><b>"concat": </b> |
| 373 | 361 the <tt>..</tt> (concatenation) operation. |
| 362 | |
| 363 Behavior similar to the "add" operation. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
364 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
365 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
366 <li><b>"len": </b> |
| 373 | 367 the <tt>#</tt> (length) operation. |
| 368 | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
369 If there is a metamethod, |
| 373 | 370 Luan calls it with the object as argument, |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
371 and the result of the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
372 (always adjusted to one value) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
373 is the result of the operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
374 If there is no metamethod but the object is a table, |
| 373 | 375 then Luan uses the table length operation (see <a href="#3.4.7">§3.4.7</a>). |
| 376 Otherwise, Luan raises an error. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
377 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
378 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
379 <li><b>"eq": </b> |
| 373 | 380 the <tt>==</tt> (equal) operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
381 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
382 Behavior similar to the "add" operation, |
| 373 | 383 except that Luan will try a metamethod only when the values |
| 384 being compared are both tables | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
385 and they are not primitively equal. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
386 The result of the call is always converted to a boolean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
387 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
388 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
389 <li><b>"lt": </b> |
| 373 | 390 the <tt><</tt> (less than) operation. |
| 391 | |
| 392 Behavior similar to the "add" operation. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
393 The result of the call is always converted to a boolean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
394 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
395 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
396 <li><b>"le": </b> |
| 373 | 397 the <tt><=</tt> (less equal) operation. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
398 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
399 Unlike other operations, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
400 The less-equal operation can use two different events. |
| 373 | 401 First, Luan looks for the "<tt>__le</tt>" metamethod in both operands, |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
402 like in the "lt" operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
403 If it cannot find such a metamethod, |
| 373 | 404 then it will try the "<tt>__lt</tt>" event, |
| 405 assuming that <tt>a <= b</tt> is equivalent to <tt>not (b < a)</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
406 As with the other comparison operators, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
407 the result is always a boolean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
408 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
409 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
410 <li><b>"index": </b> |
| 373 | 411 The indexing access <tt>table[key]</tt>. |
| 412 | |
| 413 This event happens | |
| 414 when <tt>key</tt> is not present in <tt>table</tt>. | |
| 415 The metamethod is looked up in <tt>table</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
416 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
418 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
419 Despite the name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
420 the metamethod for this event can be either a function or a table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
421 If it is a function, |
| 373 | 422 it is called with <tt>table</tt> and <tt>key</tt> as arguments. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
423 If it is a table, |
| 373 | 424 the final result is the result of indexing this table with <tt>key</tt>. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
425 (This indexing is regular, not raw, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
426 and therefore can trigger another metamethod.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
427 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
428 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
429 <li><b>"newindex": </b> |
| 373 | 430 The indexing assignment <tt>table[key] = value</tt>. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
431 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
432 Like the index event, |
| 373 | 433 this event happens when |
| 434 when <tt>key</tt> is not present in <tt>table</tt>. | |
| 435 The metamethod is looked up in <tt>table</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
436 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
437 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
438 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
439 Like with indexing, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
440 the metamethod for this event can be either a function or a table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
441 If it is a function, |
| 373 | 442 it is called with <tt>table</tt>, <tt>key</tt>, and <tt>value</tt> as arguments. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
443 If it is a table, |
| 373 | 444 Luan does an indexing assignment to this table with the same key and value. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
445 (This assignment is regular, not raw, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
446 and therefore can trigger another metamethod.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
448 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
449 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
450 Whenever there is a "newindex" metamethod, |
| 373 | 451 Luan does not perform the primitive assignment. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
452 (If necessary, |
| 373 | 453 the metamethod itself can call <a href="#pdf-rawset"><tt>raw_set</tt></a> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
454 to do the assignment.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
455 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
456 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
457 <li><b>"call": </b> |
| 373 | 458 The call operation <tt>func(args)</tt>. |
| 459 | |
| 460 This event happens when Luan tries to call a table. | |
| 461 The metamethod is looked up in <tt>func</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
462 If present, |
| 373 | 463 the metamethod is called with <tt>func</tt> as its first argument, |
| 464 followed by the arguments of the original call (<tt>args</tt>). | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
465 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
466 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
467 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
468 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
469 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
470 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
471 |
| 380 | 472 <h3 margin-top="1em"><a name="gc">Garbage Collection</a></h3> |
| 473 | |
| 474 <p> | |
| 475 Luan uses Java's garbage collection. | |
| 476 | |
| 477 | |
| 478 | |
| 479 | |
| 480 | |
| 481 <h2 margin-top="1em"><a name="lang">The Language</a></h2> | |
| 482 | |
| 483 <p> | |
| 484 This section describes the lexis, the syntax, and the semantics of Luan. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
485 In other words, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
486 this section describes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
487 which tokens are valid, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
488 how they can be combined, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
489 and what their combinations mean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
490 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
491 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
492 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
493 Language constructs will be explained using the usual extended BNF notation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
494 in which |
| 380 | 495 {<i>a</i>} means 0 or more <i>a</i>'s, and |
| 496 [<i>a</i>] means an optional <i>a</i>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
497 Non-terminals are shown like non-terminal, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
498 keywords are shown like <b>kword</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
499 and other terminal symbols are shown like ‘<b>=</b>’. |
| 380 | 500 The complete syntax of Luan can be found in <a href="#9">§9</a> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
501 at the end of this manual. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
502 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
503 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
504 |
| 380 | 505 <h3 margin-top="1em"><a name="lex">Lexical Conventions</a></h3> |
| 506 | |
| 507 <p> | |
| 508 Luan ignores spaces and comments | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
509 between lexical elements (tokens), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
510 except as delimiters between names and keywords. |
| 380 | 511 Luan generally considers the end of a line to be the end of a statement. This catches errors and encourages readability. The exception to this is in paranthesis ( <i>(...)</i>, <i>[...]</i>, and <i>{...}</i> ) where the end of line is treated as white space. |
| 512 | |
| 513 <p> | |
| 514 <i>Names</i> | |
| 515 (also called <i>identifiers</i>) | |
| 516 in Luan can be any string of letters, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
517 digits, and underscores, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
518 not beginning with a digit. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
519 Identifiers are used to name variables, table fields, and labels. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
520 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
521 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
522 <p> |
| 380 | 523 The following <i>keywords</i> are reserved |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
524 and cannot be used as names: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
526 |
| 382 | 527 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
528 and break do else elseif end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
529 false for function goto if in |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
530 local nil not or repeat return |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
531 then true until while |
| 382 | 532 </pre></p> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
533 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
534 <p> |
| 380 | 535 Luan is a case-sensitive language: |
| 536 <tt>and</tt> is a reserved word, but <tt>And</tt> and <tt>AND</tt> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
537 are two different, valid names. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
540 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
541 The following strings denote other tokens: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
542 |
| 382 | 543 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
544 + - * / % ^ # |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
545 & ~ | << >> // |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
546 == ~= <= >= < > = |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
547 ( ) { } [ ] :: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
548 ; : , . .. ... |
| 382 | 549 </pre></p> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
550 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
551 <p> |
| 380 | 552 <i>Literal strings</i> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
553 can be delimited by matching single or double quotes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
554 and can contain the following C-like escape sequences: |
| 380 | 555 '<tt>\a</tt>' (bell), |
| 556 '<tt>\b</tt>' (backspace), | |
| 557 '<tt>\f</tt>' (form feed), | |
| 558 '<tt>\n</tt>' (newline), | |
| 559 '<tt>\r</tt>' (carriage return), | |
| 560 '<tt>\t</tt>' (horizontal tab), | |
| 561 '<tt>\v</tt>' (vertical tab), | |
| 562 '<tt>\\</tt>' (backslash), | |
| 563 '<tt>\"</tt>' (quotation mark [double quote]), | |
| 564 and '<tt>\'</tt>' (apostrophe [single quote]). | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
565 A backslash followed by a real newline |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
566 results in a newline in the string. |
| 380 | 567 The escape sequence '<tt>\z</tt>' skips the following span |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
568 of white-space characters, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
569 including line breaks; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
570 it is particularly useful to break and indent a long literal string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
571 into multiple lines without adding the newlines and spaces |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
572 into the string contents. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
573 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
574 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
575 <p> |
| 380 | 576 Luan can specify any character in a literal string by its numerical value. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
577 This can be done |
| 380 | 578 with the escape sequence <tt>\x<i>XX</i></tt>, |
| 579 where <i>XX</i> is a sequence of exactly two hexadecimal digits, | |
| 580 or with the escape sequence <tt>\<i>ddd</i></tt>, | |
| 581 where <i>ddd</i> is a sequence of up to three decimal digits. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
582 (Note that if a decimal escape sequence is to be followed by a digit, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
583 it must be expressed using exactly three digits.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
584 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
585 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
586 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
587 Literal strings can also be defined using a long format |
| 380 | 588 enclosed by <i>long brackets</i>. |
| 589 We define an <i>opening long bracket of level <i>n</i></i> as an opening | |
| 590 square bracket followed by <i>n</i> equal signs followed by another | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
591 opening square bracket. |
| 380 | 592 So, an opening long bracket of level 0 is written as <tt>[[</tt>, |
| 593 an opening long bracket of level 1 is written as <tt>[=[</tt>, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
594 and so on. |
| 380 | 595 A <i>closing long bracket</i> is defined similarly; |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
596 for instance, |
| 380 | 597 a closing long bracket of level 4 is written as <tt>]====]</tt>. |
| 598 A <i>long literal</i> starts with an opening long bracket of any level and | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
599 ends at the first closing long bracket of the same level. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
600 It can contain any text except a closing bracket of the same level. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
601 Literals in this bracketed form can run for several lines, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
602 do not interpret any escape sequences, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
603 and ignore long brackets of any other level. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
604 Any kind of end-of-line sequence |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
605 (carriage return, newline, carriage return followed by newline, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
606 or newline followed by carriage return) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
607 is converted to a simple newline. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
608 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
609 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
610 <p> |
| 380 | 611 Any character in a literal string not |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
612 explicitly affected by the previous rules represents itself. |
| 380 | 613 However, Luan opens files for parsing in text mode, |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
614 and the system file functions may have problems with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
615 some control characters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
616 So, it is safer to represent |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
617 non-text data as a quoted literal with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
618 explicit escape sequences for non-text characters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
619 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
620 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
621 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
622 For convenience, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
623 when the opening long bracket is immediately followed by a newline, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
624 the newline is not included in the string. |
| 380 | 625 As an example |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
626 the five literal strings below denote the same string: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
627 |
| 382 | 628 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
629 a = 'alo\n123"' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
630 a = "alo\n123\"" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
631 a = '\97lo\10\04923"' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
632 a = [[alo |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
633 123"]] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
634 a = [==[ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
635 alo |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
636 123"]==] |
| 382 | 637 </pre></p> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
638 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
639 <p> |
| 380 | 640 A <i>numerical constant</i> (or <i>numeral</i>) |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
641 can be written with an optional fractional part |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
642 and an optional decimal exponent, |
| 380 | 643 marked by a letter '<tt>e</tt>' or '<tt>E</tt>'. |
| 644 Luan also accepts hexadecimal constants, | |
| 645 which start with <tt>0x</tt> or <tt>0X</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
646 Hexadecimal constants also accept an optional fractional part |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
647 plus an optional binary exponent, |
| 380 | 648 marked by a letter '<tt>p</tt>' or '<tt>P</tt>'. |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
649 A numeric constant with a fractional dot or an exponent |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
650 denotes a float; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
651 otherwise it denotes an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
652 Examples of valid integer constants are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
653 |
| 382 | 654 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
655 3 345 0xff 0xBEBADA |
| 382 | 656 </pre></p> |
| 657 | |
| 658 <p> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
659 Examples of valid float constants are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
660 |
| 382 | 661 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
662 3.0 3.1416 314.16e-2 0.31416E1 34e1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
663 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1 |
| 382 | 664 </pre></p> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
665 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
666 <p> |
| 380 | 667 A <i>comment</i> starts with a double hyphen (<tt>--</tt>) |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
668 anywhere outside a string. |
| 380 | 669 If the text immediately after <tt>--</tt> is not an opening long bracket, |
| 670 the comment is a <i>short comment</i>, | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
671 which runs until the end of the line. |
| 380 | 672 Otherwise, it is a <i>long comment</i>, |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
673 which runs until the corresponding closing long bracket. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
674 Long comments are frequently used to disable code temporarily. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
675 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
676 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
677 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
678 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
679 |
| 380 | 680 <h3 margin-top="1em"><a name="vars">Variables</a></h3> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
681 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
682 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
683 Variables are places that store values. |
| 380 | 684 There are three kinds of variables in Luan: |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
685 global variables, local variables, and table fields. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
686 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
687 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
688 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
689 A single name can denote a global variable or a local variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
690 (or a function's formal parameter, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
691 which is a particular kind of local variable): |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
692 |
| 382 | 693 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
694 var ::= Name |
| 382 | 695 </pre></p> |
| 696 | |
| 697 <p> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
698 Name denotes identifiers, as defined in <a href="#3.1">§3.1</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
699 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
700 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
701 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
702 Any variable name is assumed to be global unless explicitly declared |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
703 as a local (see <a href="#3.3.7">§3.3.7</a>). |
| 380 | 704 Local variables are <i>lexically scoped</i>: |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
705 local variables can be freely accessed by functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
706 defined inside their scope (see <a href="#3.5">§3.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
707 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
708 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
709 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
710 Before the first assignment to a variable, its value is <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
711 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
712 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
713 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
714 Square brackets are used to index a table: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
715 |
| 382 | 716 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
717 var ::= prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’ |
| 382 | 718 </pre></p> |
| 719 | |
| 720 <p> | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
721 The meaning of accesses to table fields can be changed via metatables. |
| 380 | 722 An access to an indexed variable <tt>t[i]</tt> is equivalent to |
| 723 a call <tt>gettable_event(t,i)</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
724 (See <a href="#2.4">§2.4</a> for a complete description of the |
| 380 | 725 <tt>gettable_event</tt> function. |
| 726 This function is not defined or callable in Luan. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
727 We use it here only for explanatory purposes.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
728 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
729 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
730 <p> |
| 380 | 731 The syntax <tt>var.Name</tt> is just syntactic sugar for |
| 732 <tt>var["Name"]</tt>: | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
733 |
| 382 | 734 <p><pre> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
735 var ::= prefixexp ‘<b>.</b>’ Name |
| 382 | 736 </pre></p> |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
738 <p> |
| 380 | 739 An access to a global variable <tt>x</tt> |
| 740 is equivalent to <tt>_ENV.x</tt>. | |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
741 Due to the way that chunks are compiled, |
| 380 | 742 <tt>_ENV</tt> is never a global name (see <a href="#2.2">§2.2</a>). |
|
371
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
743 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
744 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
745 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
746 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
747 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
748 <h2>3.3 – <a name="3.3">Statements</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
749 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
750 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
751 Lua supports an almost conventional set of statements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
752 similar to those in Pascal or C. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
753 This set includes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
754 assignments, control structures, function calls, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
755 and variable declarations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
756 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
757 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
758 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
759 <h3>3.3.1 – <a name="3.3.1">Blocks</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
760 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
761 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
762 A block is a list of statements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
763 which are executed sequentially: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
764 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
765 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
766 block ::= {stat} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
767 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
768 Lua has <em>empty statements</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
769 that allow you to separate statements with semicolons, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
770 start a block with a semicolon |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
771 or write two semicolons in sequence: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
772 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
773 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
774 stat ::= ‘<b>;</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
775 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
776 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
777 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
778 Function calls and assignments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
779 can start with an open parenthesis. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
780 This possibility leads to an ambiguity in Lua's grammar. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
781 Consider the following fragment: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
782 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
783 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
784 a = b + c |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
785 (print or io.write)('done') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
786 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
787 The grammar could see it in two ways: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
788 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
789 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
790 a = b + c(print or io.write)('done') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
792 a = b + c; (print or io.write)('done') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
793 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
794 The current parser always sees such constructions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
795 in the first way, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
796 interpreting the open parenthesis |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
797 as the start of the arguments to a call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
798 To avoid this ambiguity, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
799 it is a good practice to always precede with a semicolon |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
800 statements that start with a parenthesis: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
802 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
803 ;(print or io.write)('done') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
804 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
805 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
806 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
807 A block can be explicitly delimited to produce a single statement: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
808 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
809 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
810 stat ::= <b>do</b> block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
811 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
812 Explicit blocks are useful |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
813 to control the scope of variable declarations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
814 Explicit blocks are also sometimes used to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
815 add a <b>return</b> statement in the middle |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
816 of another block (see <a href="#3.3.4">§3.3.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
817 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
818 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
819 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
822 <h3>3.3.2 – <a name="3.3.2">Chunks</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
823 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
824 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
825 The unit of compilation of Lua is called a <em>chunk</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
826 Syntactically, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
827 a chunk is simply a block: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
828 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
829 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
830 chunk ::= block |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
831 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
833 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
834 Lua handles a chunk as the body of an anonymous function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
835 with a variable number of arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
836 (see <a href="#3.4.11">§3.4.11</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
837 As such, chunks can define local variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
838 receive arguments, and return values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
839 Moreover, such anonymous function is compiled as in the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
840 scope of an external local variable called <code>_ENV</code> (see <a href="#2.2">§2.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
841 The resulting function always has <code>_ENV</code> as its only upvalue, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
842 even if it does not use that variable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
843 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
844 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
845 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
846 A chunk can be stored in a file or in a string inside the host program. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
847 To execute a chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
848 Lua first <em>loads</em> it, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
849 precompiling the chunk's code into instructions for a virtual machine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
850 and then Lua executes the compiled code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
851 with an interpreter for the virtual machine. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
852 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
853 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
854 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
855 Chunks can also be precompiled into binary form; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
856 see program <code>luac</code> and function <a href="#pdf-string.dump"><code>string.dump</code></a> for details. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
857 Programs in source and compiled forms are interchangeable; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
858 Lua automatically detects the file type and acts accordingly (see <a href="#pdf-load"><code>load</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
859 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
860 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
861 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
862 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
863 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
864 <h3>3.3.3 – <a name="3.3.3">Assignment</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
866 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
867 Lua allows multiple assignments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
868 Therefore, the syntax for assignment |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
869 defines a list of variables on the left side |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
870 and a list of expressions on the right side. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
871 The elements in both lists are separated by commas: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
872 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
873 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
874 stat ::= varlist ‘<b>=</b>’ explist |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
875 varlist ::= var {‘<b>,</b>’ var} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
876 explist ::= exp {‘<b>,</b>’ exp} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
877 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
878 Expressions are discussed in <a href="#3.4">§3.4</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
879 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
880 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
881 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
882 Before the assignment, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
883 the list of values is <em>adjusted</em> to the length of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
884 the list of variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
885 If there are more values than needed, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
886 the excess values are thrown away. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
887 If there are fewer values than needed, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
888 the list is extended with as many <b>nil</b>'s as needed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
889 If the list of expressions ends with a function call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
890 then all values returned by that call enter the list of values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
891 before the adjustment |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
892 (except when the call is enclosed in parentheses; see <a href="#3.4">§3.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
893 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
894 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
895 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
896 The assignment statement first evaluates all its expressions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
897 and only then the assignments are performed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
898 Thus the code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
899 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
900 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
901 i = 3 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
902 i, a[i] = i+1, 20 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
903 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
904 sets <code>a[3]</code> to 20, without affecting <code>a[4]</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
905 because the <code>i</code> in <code>a[i]</code> is evaluated (to 3) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
906 before it is assigned 4. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
907 Similarly, the line |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
908 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
909 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
910 x, y = y, x |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
911 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
912 exchanges the values of <code>x</code> and <code>y</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
913 and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
914 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
915 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
916 x, y, z = y, z, x |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
917 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
918 cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
919 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
920 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
921 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
922 The meaning of assignments to global variables |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
923 and table fields can be changed via metatables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
924 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
925 <code>settable_event(t,i,val)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
926 (See <a href="#2.4">§2.4</a> for a complete description of the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
927 <code>settable_event</code> function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
928 This function is not defined or callable in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
929 We use it here only for explanatory purposes.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
930 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
931 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
932 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
933 An assignment to a global name <code>x = val</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
934 is equivalent to the assignment |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
935 <code>_ENV.x = val</code> (see <a href="#2.2">§2.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
937 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
938 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
939 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
941 <h3>3.3.4 – <a name="3.3.4">Control Structures</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
942 The control structures |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
943 <b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
944 familiar syntax: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
945 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
946 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
947 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
948 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
949 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
950 stat ::= <b>while</b> exp <b>do</b> block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
951 stat ::= <b>repeat</b> block <b>until</b> exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
952 stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
953 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
954 Lua also has a <b>for</b> statement, in two flavors (see <a href="#3.3.5">§3.3.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
955 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
956 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
957 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
958 The condition expression of a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
959 control structure can return any value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
960 Both <b>false</b> and <b>nil</b> are considered false. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
961 All values different from <b>nil</b> and <b>false</b> are considered true |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
962 (in particular, the number 0 and the empty string are also true). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
964 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
965 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
966 In the <b>repeat</b>–<b>until</b> loop, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
967 the inner block does not end at the <b>until</b> keyword, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
968 but only after the condition. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
969 So, the condition can refer to local variables |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
970 declared inside the loop block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
971 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
972 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
973 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
974 The <b>goto</b> statement transfers the program control to a label. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
975 For syntactical reasons, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
976 labels in Lua are considered statements too: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
977 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
978 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
979 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
980 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
981 stat ::= <b>goto</b> Name |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
982 stat ::= label |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
983 label ::= ‘<b>::</b>’ Name ‘<b>::</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
984 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
986 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
987 A label is visible in the entire block where it is defined, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
988 except |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
989 inside nested blocks where a label with the same name is defined and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
990 inside nested functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
991 A goto may jump to any visible label as long as it does not |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
992 enter into the scope of a local variable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
995 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
996 Labels and empty statements are called <em>void statements</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
997 as they perform no actions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
998 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
999 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1000 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1001 The <b>break</b> statement terminates the execution of a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1002 <b>while</b>, <b>repeat</b>, or <b>for</b> loop, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1003 skipping to the next statement after the loop: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1006 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1007 stat ::= <b>break</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1008 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1009 A <b>break</b> ends the innermost enclosing loop. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1010 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1011 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1012 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1013 The <b>return</b> statement is used to return values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1014 from a function or a chunk |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1015 (which is an anonymous function). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1016 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1017 Functions can return more than one value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1018 so the syntax for the <b>return</b> statement is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1019 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1020 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1021 stat ::= <b>return</b> [explist] [‘<b>;</b>’] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1022 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1023 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1024 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1025 The <b>return</b> statement can only be written |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1026 as the last statement of a block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1027 If it is really necessary to <b>return</b> in the middle of a block, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1028 then an explicit inner block can be used, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1029 as in the idiom <code>do return end</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1030 because now <b>return</b> is the last statement in its (inner) block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1031 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1034 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1035 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1036 <h3>3.3.5 – <a name="3.3.5">For Statement</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1037 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1038 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1039 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1040 The <b>for</b> statement has two forms: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1041 one numeric and one generic. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1042 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1043 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1044 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1045 The numeric <b>for</b> loop repeats a block of code while a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1046 control variable runs through an arithmetic progression. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1047 It has the following syntax: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1048 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1049 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1050 stat ::= <b>for</b> Name ‘<b>=</b>’ exp ‘<b>,</b>’ exp [‘<b>,</b>’ exp] <b>do</b> block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1051 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1052 The <em>block</em> is repeated for <em>name</em> starting at the value of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1053 the first <em>exp</em>, until it passes the second <em>exp</em> by steps of the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1054 third <em>exp</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1055 More precisely, a <b>for</b> statement like |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1057 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1058 for v = <em>e1</em>, <em>e2</em>, <em>e3</em> do <em>block</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1059 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1060 is equivalent to the code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1061 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1062 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1063 do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1064 local <em>var</em>, <em>limit</em>, <em>step</em> = tonumber(<em>e1</em>), tonumber(<em>e2</em>), tonumber(<em>e3</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1065 if not (<em>var</em> and <em>limit</em> and <em>step</em>) then error() end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1066 <em>var</em> = <em>var</em> - <em>step</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1067 while true do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1068 <em>var</em> = <em>var</em> + <em>step</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1069 if (<em>step</em> >= 0 and <em>var</em> > <em>limit</em>) or (<em>step</em> < 0 and <em>var</em> < <em>limit</em>) then |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1070 break |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1071 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1072 local v = <em>var</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1073 <em>block</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1074 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1075 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1076 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1077 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1078 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1079 Note the following: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1080 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1081 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1083 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1084 All three control expressions are evaluated only once, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1085 before the loop starts. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1086 They must all result in numbers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1087 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1088 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1089 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1090 <code><em>var</em></code>, <code><em>limit</em></code>, and <code><em>step</em></code> are invisible variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1091 The names shown here are for explanatory purposes only. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1092 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1093 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1094 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1095 If the third expression (the step) is absent, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1096 then a step of 1 is used. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1097 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1099 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1100 You can use <b>break</b> and <b>goto</b> to exit a <b>for</b> loop. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1101 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1102 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1103 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1104 The loop variable <code>v</code> is local to the loop body. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1105 If you need its value after the loop, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1106 assign it to another variable before exiting the loop. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1107 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1109 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1110 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1111 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1112 The generic <b>for</b> statement works over functions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1113 called <em>iterators</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1114 On each iteration, the iterator function is called to produce a new value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1115 stopping when this new value is <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1116 The generic <b>for</b> loop has the following syntax: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1117 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1118 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1119 stat ::= <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1120 namelist ::= Name {‘<b>,</b>’ Name} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1121 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1122 A <b>for</b> statement like |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1123 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1124 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1125 for <em>var_1</em>, ···, <em>var_n</em> in <em>explist</em> do <em>block</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1126 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1127 is equivalent to the code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1128 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1129 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1130 do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1131 local <em>f</em>, <em>s</em>, <em>var</em> = <em>explist</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1132 while true do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1133 local <em>var_1</em>, ···, <em>var_n</em> = <em>f</em>(<em>s</em>, <em>var</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1134 if <em>var_1</em> == nil then break end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1135 <em>var</em> = <em>var_1</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1136 <em>block</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1137 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1138 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1139 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1140 Note the following: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1142 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1144 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1145 <code><em>explist</em></code> is evaluated only once. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1146 Its results are an <em>iterator</em> function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1147 a <em>state</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1148 and an initial value for the first <em>iterator variable</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1149 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1150 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1151 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1152 <code><em>f</em></code>, <code><em>s</em></code>, and <code><em>var</em></code> are invisible variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1153 The names are here for explanatory purposes only. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1154 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1156 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1157 You can use <b>break</b> to exit a <b>for</b> loop. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1158 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1159 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1160 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1161 The loop variables <code><em>var_i</em></code> are local to the loop; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1162 you cannot use their values after the <b>for</b> ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1163 If you need these values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1164 then assign them to other variables before breaking or exiting the loop. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1165 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1166 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1167 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1169 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1170 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1171 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1172 <h3>3.3.6 – <a name="3.3.6">Function Calls as Statements</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1173 To allow possible side-effects, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1174 function calls can be executed as statements: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1175 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1176 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1177 stat ::= functioncall |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1178 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1179 In this case, all returned values are thrown away. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1180 Function calls are explained in <a href="#3.4.10">§3.4.10</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1182 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1183 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1185 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1186 <h3>3.3.7 – <a name="3.3.7">Local Declarations</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1187 Local variables can be declared anywhere inside a block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1188 The declaration can include an initial assignment: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1190 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1191 stat ::= <b>local</b> namelist [‘<b>=</b>’ explist] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1192 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1193 If present, an initial assignment has the same semantics |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1194 of a multiple assignment (see <a href="#3.3.3">§3.3.3</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1195 Otherwise, all variables are initialized with <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1196 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1198 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1199 A chunk is also a block (see <a href="#3.3.2">§3.3.2</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1200 and so local variables can be declared in a chunk outside any explicit block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1202 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1203 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1204 The visibility rules for local variables are explained in <a href="#3.5">§3.5</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1206 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1207 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1208 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1210 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1211 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1212 <h2>3.4 – <a name="3.4">Expressions</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1214 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1215 The basic expressions in Lua are the following: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1216 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1217 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1218 exp ::= prefixexp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1219 exp ::= <b>nil</b> | <b>false</b> | <b>true</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1220 exp ::= Numeral |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1221 exp ::= LiteralString |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1222 exp ::= functiondef |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1223 exp ::= tableconstructor |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1224 exp ::= ‘<b>...</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1225 exp ::= exp binop exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1226 exp ::= unop exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1227 prefixexp ::= var | functioncall | ‘<b>(</b>’ exp ‘<b>)</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1228 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1229 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1230 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1231 Numerals and literal strings are explained in <a href="#3.1">§3.1</a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1232 variables are explained in <a href="#3.2">§3.2</a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1233 function definitions are explained in <a href="#3.4.11">§3.4.11</a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1234 function calls are explained in <a href="#3.4.10">§3.4.10</a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1235 table constructors are explained in <a href="#3.4.9">§3.4.9</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1236 Vararg expressions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1237 denoted by three dots ('<code>...</code>'), can only be used when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1238 directly inside a vararg function; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1239 they are explained in <a href="#3.4.11">§3.4.11</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1240 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1242 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1243 Binary operators comprise arithmetic operators (see <a href="#3.4.1">§3.4.1</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1244 bitwise operators (see <a href="#3.4.2">§3.4.2</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1245 relational operators (see <a href="#3.4.4">§3.4.4</a>), logical operators (see <a href="#3.4.5">§3.4.5</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1246 and the concatenation operator (see <a href="#3.4.6">§3.4.6</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1247 Unary operators comprise the unary minus (see <a href="#3.4.1">§3.4.1</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1248 the unary bitwise not (see <a href="#3.4.2">§3.4.2</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1249 the unary logical <b>not</b> (see <a href="#3.4.5">§3.4.5</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1250 and the unary <em>length operator</em> (see <a href="#3.4.7">§3.4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1251 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1252 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1253 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1254 Both function calls and vararg expressions can result in multiple values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1255 If a function call is used as a statement (see <a href="#3.3.6">§3.3.6</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1256 then its return list is adjusted to zero elements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1257 thus discarding all returned values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1258 If an expression is used as the last (or the only) element |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1259 of a list of expressions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1260 then no adjustment is made |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1261 (unless the expression is enclosed in parentheses). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1262 In all other contexts, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1263 Lua adjusts the result list to one element, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1264 either discarding all values except the first one |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1265 or adding a single <b>nil</b> if there are no values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1267 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1268 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1269 Here are some examples: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1270 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1271 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1272 f() -- adjusted to 0 results |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1273 g(f(), x) -- f() is adjusted to 1 result |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1274 g(x, f()) -- g gets x plus all results from f() |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1275 a,b,c = f(), x -- f() is adjusted to 1 result (c gets nil) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1276 a,b = ... -- a gets the first vararg parameter, b gets |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1277 -- the second (both a and b can get nil if there |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1278 -- is no corresponding vararg parameter) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1280 a,b,c = x, f() -- f() is adjusted to 2 results |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1281 a,b,c = f() -- f() is adjusted to 3 results |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1282 return f() -- returns all results from f() |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1283 return ... -- returns all received vararg parameters |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1284 return x,y,f() -- returns x, y, and all results from f() |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1285 {f()} -- creates a list with all results from f() |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1286 {...} -- creates a list with all vararg parameters |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1287 {f(), nil} -- f() is adjusted to 1 result |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1288 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1289 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1290 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1291 Any expression enclosed in parentheses always results in only one value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1292 Thus, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1293 <code>(f(x,y,z))</code> is always a single value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1294 even if <code>f</code> returns several values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1295 (The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1296 or <b>nil</b> if <code>f</code> does not return any values.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1297 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1298 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1300 <h3>3.4.1 – <a name="3.4.1">Arithmetic Operators</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1301 Lua supports the following arithmetic operators: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1302 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1303 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1304 <li><b><code>+</code>: </b>addition</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1305 <li><b><code>-</code>: </b>subtraction</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1306 <li><b><code>*</code>: </b>multiplication</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1307 <li><b><code>/</code>: </b>float division</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1308 <li><b><code>//</code>: </b>floor division</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1309 <li><b><code>%</code>: </b>modulo</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1310 <li><b><code>^</code>: </b>exponentiation</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1311 <li><b><code>-</code>: </b>unary minus</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1312 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1313 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1314 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1315 With the exception of exponentiation and float division, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1316 the arithmetic operators work as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1317 If both operands are integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1318 the operation is performed over integers and the result is an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1319 Otherwise, if both operands are numbers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1320 or strings that can be converted to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1321 numbers (see <a href="#3.4.3">§3.4.3</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1322 then they are converted to floats, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1323 the operation is performed following the usual rules |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1324 for floating-point arithmetic |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1325 (usually the IEEE 754 standard), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1326 and the result is a float. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1327 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1328 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1329 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1330 Exponentiation and float division (<code>/</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1331 always convert their operands to floats |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1332 and the result is always a float. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1333 Exponentiation uses the ISO C function <code>pow</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1334 so that it works for non-integer exponents too. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1335 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1336 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1337 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1338 Floor division (<code>//</code>) is a division |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1339 that rounds the quotient towards minus infinite, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1340 that is, the floor of the division of its operands. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1341 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1342 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1343 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1344 Modulo is defined as the remainder of a division |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1345 that rounds the quotient towards minus infinite (floor division). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1346 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1347 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1348 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1349 In case of overflows in integer arithmetic, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1350 all operations <em>wrap around</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1351 according to the usual rules of two-complement arithmetic. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1352 (In other words, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1353 they return the unique representable integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1354 that is equal modulo <em>2<sup>64</sup></em> to the mathematical result.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1355 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1357 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1358 <h3>3.4.2 – <a name="3.4.2">Bitwise Operators</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1359 Lua supports the following bitwise operators: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1360 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1361 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1362 <li><b><code>&</code>: </b>bitwise and</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1363 <li><b><code>|</code>: </b>bitwise or</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1364 <li><b><code>~</code>: </b>bitwise exclusive or</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1365 <li><b><code>>></code>: </b>right shift</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1366 <li><b><code><<</code>: </b>left shift</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1367 <li><b><code>~</code>: </b>unary bitwise not</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1368 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1369 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1370 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1371 All bitwise operations convert its operands to integers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1372 (see <a href="#3.4.3">§3.4.3</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1373 operate on all bits of those integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1374 and result in an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1375 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1376 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1377 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1378 Both right and left shifts fill the vacant bits with zeros. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1379 Negative displacements shift to the other direction; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1380 displacements with absolute values equal to or higher than |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1381 the number of bits in an integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1382 result in zero (as all bits are shifted out). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1383 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1384 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1385 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1387 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1388 <h3>3.4.3 – <a name="3.4.3">Coercions and Conversions</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1389 Lua provides some automatic conversions between some |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1390 types and representations at run time. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1391 Bitwise operators always convert float operands to integers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1392 Exponentiation and float division |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1393 always convert integer operands to floats. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1394 All other arithmetic operations applied to mixed numbers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1395 (integers and floats) convert the integer operand to a float; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1396 this is called the <em>usual rule</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1397 The C API also converts both integers to floats and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1398 floats to integers, as needed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1399 Moreover, string concatenation accepts numbers as arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1400 besides strings. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1403 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1404 Lua also converts strings to numbers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1405 whenever a number is expected. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1406 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1407 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1408 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1409 In a conversion from integer to float, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1410 if the integer value has an exact representation as a float, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1411 that is the result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1412 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1413 the conversion gets the nearest higher or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1414 the nearest lower representable value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1415 This kind of conversion never fails. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1416 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1418 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1419 The conversion from float to integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1420 checks whether the float has an exact representation as an integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1421 (that is, the float has an integral value and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1422 it is in the range of integer representation). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1423 If it does, that representation is the result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1424 Otherwise, the conversion fails. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1425 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1426 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1427 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1428 The conversion from strings to numbers goes as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1429 First, the string is converted to an integer or a float, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1430 following its syntax and the rules of the Lua lexer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1431 (The string may have also leading and trailing spaces and a sign.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1432 Then, the resulting number is converted to the required type |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1433 (float or integer) according to the previous rules. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1434 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1435 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1436 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1437 The conversion from numbers to strings uses a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1438 non-specified human-readable format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1439 For complete control over how numbers are converted to strings, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1440 use the <code>format</code> function from the string library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1441 (see <a href="#pdf-string.format"><code>string.format</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1443 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1444 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1445 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1446 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1447 <h3>3.4.4 – <a name="3.4.4">Relational Operators</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1448 Lua supports the following relational operators: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1449 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1450 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1451 <li><b><code>==</code>: </b>equality</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1452 <li><b><code>~=</code>: </b>inequality</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1453 <li><b><code><</code>: </b>less than</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1454 <li><b><code>></code>: </b>greater than</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1455 <li><b><code><=</code>: </b>less or equal</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1456 <li><b><code>>=</code>: </b>greater or equal</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1457 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1458 These operators always result in <b>false</b> or <b>true</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1459 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1460 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1461 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1462 Equality (<code>==</code>) first compares the type of its operands. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1463 If the types are different, then the result is <b>false</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1464 Otherwise, the values of the operands are compared. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1465 Strings are compared in the obvious way. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1466 Numbers follow the usual rule for binary operations: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1467 if both operands are integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1468 they are compared as integers; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1469 otherwise, they are converted to floats |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1470 and compared as such. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1472 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1473 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1474 Tables, userdata, and threads |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1475 are compared by reference: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1476 two objects are considered equal only if they are the same object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1477 Every time you create a new object |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1478 (a table, userdata, or thread), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1479 this new object is different from any previously existing object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1480 Closures with the same reference are always equal. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1481 Closures with any detectable difference |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1482 (different behavior, different definition) are always different. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1484 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1485 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1486 You can change the way that Lua compares tables and userdata |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1487 by using the "eq" metamethod (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1488 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1489 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1490 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1491 Equality comparisons do not convert strings to numbers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1492 or vice versa. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1493 Thus, <code>"0"==0</code> evaluates to <b>false</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1494 and <code>t[0]</code> and <code>t["0"]</code> denote different |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1495 entries in a table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1496 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1497 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1498 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1499 The operator <code>~=</code> is exactly the negation of equality (<code>==</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1500 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1501 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1502 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1503 The order operators work as follows. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1504 If both arguments are numbers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1505 then they are compared following |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1506 the usual rule for binary operations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1507 Otherwise, if both arguments are strings, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1508 then their values are compared according to the current locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1509 Otherwise, Lua tries to call the "lt" or the "le" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1510 metamethod (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1511 A comparison <code>a > b</code> is translated to <code>b < a</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1512 and <code>a >= b</code> is translated to <code>b <= a</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1513 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1514 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1515 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1516 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1517 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1518 <h3>3.4.5 – <a name="3.4.5">Logical Operators</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1519 The logical operators in Lua are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1520 <b>and</b>, <b>or</b>, and <b>not</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1521 Like the control structures (see <a href="#3.3.4">§3.3.4</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1522 all logical operators consider both <b>false</b> and <b>nil</b> as false |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1523 and anything else as true. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1524 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1526 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1527 The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1528 The conjunction operator <b>and</b> returns its first argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1529 if this value is <b>false</b> or <b>nil</b>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1530 otherwise, <b>and</b> returns its second argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1531 The disjunction operator <b>or</b> returns its first argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1532 if this value is different from <b>nil</b> and <b>false</b>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1533 otherwise, <b>or</b> returns its second argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1534 Both <b>and</b> and <b>or</b> use short-circuit evaluation; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1535 that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1536 the second operand is evaluated only if necessary. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1537 Here are some examples: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1539 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1540 10 or 20 --> 10 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1541 10 or error() --> 10 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1542 nil or "a" --> "a" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1543 nil and 10 --> nil |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1544 false and error() --> false |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1545 false and nil --> false |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1546 false or nil --> nil |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1547 10 and 20 --> 20 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1548 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1549 (In this manual, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1550 <code>--></code> indicates the result of the preceding expression.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1551 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1552 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1553 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1554 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1555 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1556 <h3>3.4.6 – <a name="3.4.6">Concatenation</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1557 The string concatenation operator in Lua is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1558 denoted by two dots ('<code>..</code>'). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1559 If both operands are strings or numbers, then they are converted to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1560 strings according to the rules described in <a href="#3.4.3">§3.4.3</a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1561 Otherwise, the <code>__concat</code> metamethod is called (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1562 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1563 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1564 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1566 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1567 <h3>3.4.7 – <a name="3.4.7">The Length Operator</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1568 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1569 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1570 The length operator is denoted by the unary prefix operator <code>#</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1571 The length of a string is its number of bytes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1572 (that is, the usual meaning of string length when each |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1573 character is one byte). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1574 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1575 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1576 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1577 A program can modify the behavior of the length operator for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1578 any value but strings through the <code>__len</code> metamethod (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1579 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1580 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1581 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1582 Unless a <code>__len</code> metamethod is given, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1583 the length of a table <code>t</code> is only defined if the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1584 table is a <em>sequence</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1585 that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1586 the set of its positive numeric keys is equal to <em>{1..n}</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1587 for some non-negative integer <em>n</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1588 In that case, <em>n</em> is its length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1589 Note that a table like |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1590 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1591 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1592 {10, 20, nil, 40} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1593 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1594 is not a sequence, because it has the key <code>4</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1595 but does not have the key <code>3</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1596 (So, there is no <em>n</em> such that the set <em>{1..n}</em> is equal |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1597 to the set of positive numeric keys of that table.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1598 Note, however, that non-numeric keys do not interfere |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1599 with whether a table is a sequence. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1600 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1601 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1602 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1603 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1604 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1605 <h3>3.4.8 – <a name="3.4.8">Precedence</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1606 Operator precedence in Lua follows the table below, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1607 from lower to higher priority: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1608 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1609 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1610 or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1611 and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1612 < > <= >= ~= == |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1613 | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1614 ~ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1615 & |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1616 << >> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1617 .. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1618 + - |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1619 * / // % |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1620 unary operators (not # - ~) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1621 ^ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1622 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1623 As usual, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1624 you can use parentheses to change the precedences of an expression. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1625 The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1626 operators are right associative. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1627 All other binary operators are left associative. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1628 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1629 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1630 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1631 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1632 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1633 <h3>3.4.9 – <a name="3.4.9">Table Constructors</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1634 Table constructors are expressions that create tables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1635 Every time a constructor is evaluated, a new table is created. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1636 A constructor can be used to create an empty table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1637 or to create a table and initialize some of its fields. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1638 The general syntax for constructors is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1639 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1640 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1641 tableconstructor ::= ‘<b>{</b>’ [fieldlist] ‘<b>}</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1642 fieldlist ::= field {fieldsep field} [fieldsep] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1643 field ::= ‘<b>[</b>’ exp ‘<b>]</b>’ ‘<b>=</b>’ exp | Name ‘<b>=</b>’ exp | exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1644 fieldsep ::= ‘<b>,</b>’ | ‘<b>;</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1645 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1647 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1648 Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1649 with key <code>exp1</code> and value <code>exp2</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1650 A field of the form <code>name = exp</code> is equivalent to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1651 <code>["name"] = exp</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1652 Finally, fields of the form <code>exp</code> are equivalent to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1653 <code>[i] = exp</code>, where <code>i</code> are consecutive integers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1654 starting with 1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1655 Fields in the other formats do not affect this counting. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1656 For example, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1657 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1658 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1659 a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1660 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1661 is equivalent to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1663 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1664 do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1665 local t = {} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1666 t[f(1)] = g |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1667 t[1] = "x" -- 1st exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1668 t[2] = "y" -- 2nd exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1669 t.x = 1 -- t["x"] = 1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1670 t[3] = f(x) -- 3rd exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1671 t[30] = 23 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1672 t[4] = 45 -- 4th exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1673 a = t |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1674 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1675 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1676 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1677 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1678 The order of the assignments in a constructor is undefined. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1679 (This order would be relevant only when there are repeated keys.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1680 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1681 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1682 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1683 If the last field in the list has the form <code>exp</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1684 and the expression is a function call or a vararg expression, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1685 then all values returned by this expression enter the list consecutively |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1686 (see <a href="#3.4.10">§3.4.10</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1687 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1688 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1689 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1690 The field list can have an optional trailing separator, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1691 as a convenience for machine-generated code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1692 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1693 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1694 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1696 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1697 <h3>3.4.10 – <a name="3.4.10">Function Calls</a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1698 A function call in Lua has the following syntax: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1699 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1700 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1701 functioncall ::= prefixexp args |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1702 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1703 In a function call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1704 first prefixexp and args are evaluated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1705 If the value of prefixexp has type <em>function</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1706 then this function is called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1707 with the given arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1708 Otherwise, the prefixexp "call" metamethod is called, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1709 having as first parameter the value of prefixexp, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1710 followed by the original call arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1711 (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1712 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1713 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1714 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1715 The form |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1716 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1717 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1718 functioncall ::= prefixexp ‘<b>:</b>’ Name args |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1719 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1720 can be used to call "methods". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1721 A call <code>v:name(<em>args</em>)</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1722 is syntactic sugar for <code>v.name(v,<em>args</em>)</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1723 except that <code>v</code> is evaluated only once. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1726 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1727 Arguments have the following syntax: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1728 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1729 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1730 args ::= ‘<b>(</b>’ [explist] ‘<b>)</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1731 args ::= tableconstructor |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1732 args ::= LiteralString |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1733 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1734 All argument expressions are evaluated before the call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1735 A call of the form <code>f{<em>fields</em>}</code> is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1736 syntactic sugar for <code>f({<em>fields</em>})</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1737 that is, the argument list is a single new table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1738 A call of the form <code>f'<em>string</em>'</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1739 (or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1740 is syntactic sugar for <code>f('<em>string</em>')</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1741 that is, the argument list is a single literal string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1742 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1743 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1744 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1745 A call of the form <code>return <em>functioncall</em></code> is called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1746 a <em>tail call</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1747 Lua implements <em>proper tail calls</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1748 (or <em>proper tail recursion</em>): |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1749 in a tail call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1750 the called function reuses the stack entry of the calling function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1751 Therefore, there is no limit on the number of nested tail calls that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1752 a program can execute. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1753 However, a tail call erases any debug information about the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1754 calling function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1755 Note that a tail call only happens with a particular syntax, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1756 where the <b>return</b> has one single function call as argument; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1757 this syntax makes the calling function return exactly |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1758 the returns of the called function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1759 So, none of the following examples are tail calls: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1760 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1761 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1762 return (f(x)) -- results adjusted to 1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1763 return 2 * f(x) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1764 return x, f(x) -- additional results |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1765 f(x); return -- results discarded |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1766 return x or f(x) -- results adjusted to 1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1767 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1768 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1769 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1770 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1771 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1772 <h3>3.4.11 – <a name="3.4.11">Function Definitions</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1773 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1774 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1775 The syntax for function definition is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1776 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1777 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1778 functiondef ::= <b>function</b> funcbody |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1779 funcbody ::= ‘<b>(</b>’ [parlist] ‘<b>)</b>’ block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1780 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1781 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1782 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1783 The following syntactic sugar simplifies function definitions: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1784 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1785 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1786 stat ::= <b>function</b> funcname funcbody |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1787 stat ::= <b>local</b> <b>function</b> Name funcbody |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1788 funcname ::= Name {‘<b>.</b>’ Name} [‘<b>:</b>’ Name] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1789 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1790 The statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1792 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1793 function f () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1794 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1795 translates to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1796 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1797 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1798 f = function () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1799 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1800 The statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1802 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1803 function t.a.b.c.f () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1804 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1805 translates to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1807 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1808 t.a.b.c.f = function () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1809 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1810 The statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1811 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1812 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1813 local function f () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1814 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1815 translates to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1816 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1817 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1818 local f; f = function () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1819 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1820 not to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1822 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1823 local f = function () <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1824 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1825 (This only makes a difference when the body of the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1826 contains references to <code>f</code>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1827 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1828 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1829 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1830 A function definition is an executable expression, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1831 whose value has type <em>function</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1832 When Lua precompiles a chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1833 all its function bodies are precompiled too. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1834 Then, whenever Lua executes the function definition, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1835 the function is <em>instantiated</em> (or <em>closed</em>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1836 This function instance (or <em>closure</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1837 is the final value of the expression. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1838 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1839 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1840 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1841 Parameters act as local variables that are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1842 initialized with the argument values: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1843 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1844 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1845 parlist ::= namelist [‘<b>,</b>’ ‘<b>...</b>’] | ‘<b>...</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1846 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1847 When a function is called, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1848 the list of arguments is adjusted to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1849 the length of the list of parameters, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1850 unless the function is a <em>vararg function</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1851 which is indicated by three dots ('<code>...</code>') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1852 at the end of its parameter list. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1853 A vararg function does not adjust its argument list; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1854 instead, it collects all extra arguments and supplies them |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1855 to the function through a <em>vararg expression</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1856 which is also written as three dots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1857 The value of this expression is a list of all actual extra arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1858 similar to a function with multiple results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1859 If a vararg expression is used inside another expression |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1860 or in the middle of a list of expressions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1861 then its return list is adjusted to one element. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1862 If the expression is used as the last element of a list of expressions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1863 then no adjustment is made |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1864 (unless that last expression is enclosed in parentheses). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1867 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1868 As an example, consider the following definitions: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1869 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1870 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1871 function f(a, b) end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1872 function g(a, b, ...) end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1873 function r() return 1,2,3 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1874 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1875 Then, we have the following mapping from arguments to parameters and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1876 to the vararg expression: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1877 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1878 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1879 CALL PARAMETERS |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1880 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1881 f(3) a=3, b=nil |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1882 f(3, 4) a=3, b=4 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1883 f(3, 4, 5) a=3, b=4 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1884 f(r(), 10) a=1, b=10 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1885 f(r()) a=1, b=2 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1886 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1887 g(3) a=3, b=nil, ... --> (nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1888 g(3, 4) a=3, b=4, ... --> (nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1889 g(3, 4, 5, 8) a=3, b=4, ... --> 5 8 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1890 g(5, r()) a=5, b=1, ... --> 2 3 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1891 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1892 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1893 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1894 Results are returned using the <b>return</b> statement (see <a href="#3.3.4">§3.3.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1895 If control reaches the end of a function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1896 without encountering a <b>return</b> statement, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1897 then the function returns with no results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1898 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1899 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1900 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1901 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1902 There is a system-dependent limit on the number of values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1903 that a function may return. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1904 This limit is guaranteed to be larger than 1000. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1905 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1906 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1907 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1908 The <em>colon</em> syntax |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1909 is used for defining <em>methods</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1910 that is, functions that have an implicit extra parameter <code>self</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1911 Thus, the statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1912 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1913 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1914 function t.a.b.c:f (<em>params</em>) <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1915 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1916 is syntactic sugar for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1917 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1918 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1919 t.a.b.c.f = function (self, <em>params</em>) <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1920 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1921 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1923 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1925 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1926 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1927 <h2>3.5 – <a name="3.5">Visibility Rules</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1928 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1929 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1930 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1931 Lua is a lexically scoped language. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1932 The scope of a local variable begins at the first statement after |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1933 its declaration and lasts until the last non-void statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1934 of the innermost block that includes the declaration. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1935 Consider the following example: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1937 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1938 x = 10 -- global variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1939 do -- new block |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1940 local x = x -- new 'x', with value 10 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1941 print(x) --> 10 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1942 x = x+1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1943 do -- another block |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1944 local x = x+1 -- another 'x' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1945 print(x) --> 12 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1946 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1947 print(x) --> 11 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1948 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1949 print(x) --> 10 (the global one) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1950 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1951 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1952 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1953 Notice that, in a declaration like <code>local x = x</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1954 the new <code>x</code> being declared is not in scope yet, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1955 and so the second <code>x</code> refers to the outside variable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1956 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1957 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1958 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1959 Because of the lexical scoping rules, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1960 local variables can be freely accessed by functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1961 defined inside their scope. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1962 A local variable used by an inner function is called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1963 an <em>upvalue</em>, or <em>external local variable</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1964 inside the inner function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1965 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1966 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1967 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1968 Notice that each execution of a <b>local</b> statement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1969 defines new local variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1970 Consider the following example: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1971 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1972 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1973 a = {} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1974 local x = 20 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1975 for i=1,10 do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1976 local y = 0 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1977 a[i] = function () y=y+1; return x+y end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1978 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1979 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1980 The loop creates ten closures |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1981 (that is, ten instances of the anonymous function). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1982 Each of these closures uses a different <code>y</code> variable, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1983 while all of them share the same <code>x</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1984 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1986 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1987 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1988 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1989 <h1>4 – <a name="4">The Application Program Interface</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1990 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1991 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1992 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1993 This section describes the C API for Lua, that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1994 the set of C functions available to the host program to communicate |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1995 with Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1996 All API functions and related types and constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1997 are declared in the header file <a name="pdf-lua.h"><code>lua.h</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1998 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
1999 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2000 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2001 Even when we use the term "function", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2002 any facility in the API may be provided as a macro instead. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2003 Except where stated otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2004 all such macros use each of their arguments exactly once |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2005 (except for the first argument, which is always a Lua state), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2006 and so do not generate any hidden side-effects. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2007 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2008 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2009 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2010 As in most C libraries, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2011 the Lua API functions do not check their arguments for validity or consistency. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2012 However, you can change this behavior by compiling Lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2013 with the macro <a name="pdf-LUA_USE_APICHECK"><code>LUA_USE_APICHECK</code></a> defined. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2014 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2015 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2016 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2017 <h2>4.1 – <a name="4.1">The Stack</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2019 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2020 Lua uses a <em>virtual stack</em> to pass values to and from C. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2021 Each element in this stack represents a Lua value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2022 (<b>nil</b>, number, string, etc.). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2023 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2024 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2025 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2026 Whenever Lua calls C, the called function gets a new stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2027 which is independent of previous stacks and of stacks of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2028 C functions that are still active. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2029 This stack initially contains any arguments to the C function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2030 and it is where the C function pushes its results |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2031 to be returned to the caller (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2034 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2035 For convenience, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2036 most query operations in the API do not follow a strict stack discipline. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2037 Instead, they can refer to any element in the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2038 by using an <em>index</em>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2039 A positive index represents an absolute stack position |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2040 (starting at 1); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2041 a negative index represents an offset relative to the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2042 More specifically, if the stack has <em>n</em> elements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2043 then index 1 represents the first element |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2044 (that is, the element that was pushed onto the stack first) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2045 and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2046 index <em>n</em> represents the last element; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2047 index -1 also represents the last element |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2048 (that is, the element at the top) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2049 and index <em>-n</em> represents the first element. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2051 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2052 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2053 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2054 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2055 <h2>4.2 – <a name="4.2">Stack Size</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2057 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2058 When you interact with the Lua API, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2059 you are responsible for ensuring consistency. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2060 In particular, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2061 <em>you are responsible for controlling stack overflow</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2062 You can use the function <a href="#lua_checkstack"><code>lua_checkstack</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2063 to ensure that the stack has enough space for pushing new elements. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2064 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2065 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2066 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2067 Whenever Lua calls C, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2068 it ensures that the stack has space for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2069 at least <a name="pdf-LUA_MINSTACK"><code>LUA_MINSTACK</code></a> extra slots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2070 <code>LUA_MINSTACK</code> is defined as 20, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2071 so that usually you do not have to worry about stack space |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2072 unless your code has loops pushing elements onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2073 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2074 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2075 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2076 When you call a Lua function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2077 without a fixed number of results (see <a href="#lua_call"><code>lua_call</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2078 Lua ensures that the stack has enough space for all results, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2079 but it does not ensure any extra space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2080 So, before pushing anything in the stack after such a call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2081 you should use <a href="#lua_checkstack"><code>lua_checkstack</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2083 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2084 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2085 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2086 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2087 <h2>4.3 – <a name="4.3">Valid and Acceptable Indices</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2088 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2089 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2090 Any function in the API that receives stack indices |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2091 works only with <em>valid indices</em> or <em>acceptable indices</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2092 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2093 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2094 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2095 A <em>valid index</em> is an index that refers to a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2096 real position within the stack, that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2097 its position lies between 1 and the stack top |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2098 (<code>1 ≤ abs(index) ≤ top</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2099 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2100 Usually, functions that can modify the value at an index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2101 require valid indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2102 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2103 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2104 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2105 Unless otherwise noted, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2106 any function that accepts valid indices also accepts <em>pseudo-indices</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2107 which represent some Lua values that are accessible to C code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2108 but which are not in the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2109 Pseudo-indices are used to access the registry |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2110 and the upvalues of a C function (see <a href="#4.4">§4.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2111 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2112 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2113 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2114 Functions that do not need a specific stack position, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2115 but only a value in the stack (e.g., query functions), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2116 can be called with acceptable indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2117 An <em>acceptable index</em> can be any valid index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2118 including the pseudo-indices, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2119 but it also can be any positive index after the stack top |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2120 within the space allocated for the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2121 that is, indices up to the stack size. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2122 (Note that 0 is never an acceptable index.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2123 Except when noted otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2124 functions in the API work with acceptable indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2125 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2126 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2127 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2128 Acceptable indices serve to avoid extra tests |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2129 against the stack top when querying the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2130 For instance, a C function can query its third argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2131 without the need to first check whether there is a third argument, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2132 that is, without the need to check whether 3 is a valid index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2133 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2134 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2135 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2136 For functions that can be called with acceptable indices, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2137 any non-valid index is treated as if it |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2138 contains a value of a virtual type <a name="pdf-LUA_TNONE"><code>LUA_TNONE</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2139 which behaves like a nil value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2140 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2144 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2145 <h2>4.4 – <a name="4.4">C Closures</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2146 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2147 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2148 When a C function is created, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2149 it is possible to associate some values with it, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2150 thus creating a <em>C closure</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2151 (see <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2152 these values are called <em>upvalues</em> and are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2153 accessible to the function whenever it is called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2154 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2156 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2157 Whenever a C function is called, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2158 its upvalues are located at specific pseudo-indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2159 These pseudo-indices are produced by the macro |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2160 <a href="#lua_upvalueindex"><code>lua_upvalueindex</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2161 The first value associated with a function is at position |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2162 <code>lua_upvalueindex(1)</code>, and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2163 Any access to <code>lua_upvalueindex(<em>n</em>)</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2164 where <em>n</em> is greater than the number of upvalues of the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2165 current function (but not greater than 256), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2166 produces an acceptable but invalid index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2169 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2170 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2171 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2172 <h2>4.5 – <a name="4.5">Registry</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2173 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2174 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2175 Lua provides a <em>registry</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2176 a predefined table that can be used by any C code to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2177 store whatever Lua values it needs to store. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2178 The registry table is always located at pseudo-index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2179 <a name="pdf-LUA_REGISTRYINDEX"><code>LUA_REGISTRYINDEX</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2180 which is a valid index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2181 Any C library can store data into this table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2182 but it must take care to choose keys |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2183 that are different from those used |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2184 by other libraries, to avoid collisions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2185 Typically, you should use as key a string containing your library name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2186 or a light userdata with the address of a C object in your code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2187 or any Lua object created by your code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2188 As with variable names, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2189 string keys starting with an underscore followed by |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2190 uppercase letters are reserved for Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2191 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2192 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2193 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2194 The integer keys in the registry are used |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2195 by the reference mechanism (see <a href="#luaL_ref"><code>luaL_ref</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2196 and by some predefined values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2197 Therefore, integer keys must not be used for other purposes. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2198 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2199 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2200 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2201 When you create a new Lua state, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2202 its registry comes with some predefined values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2203 These predefined values are indexed with integer keys |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2204 defined as constants in <code>lua.h</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2205 The following constants are defined: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2206 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2207 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2208 <li><b><a name="pdf-LUA_RIDX_MAINTHREAD"><code>LUA_RIDX_MAINTHREAD</code></a>: </b> At this index the registry has |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2209 the main thread of the state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2210 (The main thread is the one created together with the state.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2211 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2212 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2213 <li><b><a name="pdf-LUA_RIDX_GLOBALS"><code>LUA_RIDX_GLOBALS</code></a>: </b> At this index the registry has |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2214 the global environment. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2215 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2216 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2218 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2219 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2220 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2221 <h2>4.6 – <a name="4.6">Error Handling in C</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2222 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2223 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2224 Internally, Lua uses the C <code>longjmp</code> facility to handle errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2225 (Lua will use exceptions if you compile it as C++; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2226 search for <code>LUAI_THROW</code> in the source code for details.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2227 When Lua faces any error |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2228 (such as a memory allocation error, type errors, syntax errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2229 and runtime errors) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2230 it <em>raises</em> an error; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2231 that is, it does a long jump. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2232 A <em>protected environment</em> uses <code>setjmp</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2233 to set a recovery point; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2234 any error jumps to the most recent active recovery point. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2237 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2238 If an error happens outside any protected environment, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2239 Lua calls a <em>panic function</em> (see <a href="#lua_atpanic"><code>lua_atpanic</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2240 and then calls <code>abort</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2241 thus exiting the host application. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2242 Your panic function can avoid this exit by |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2243 never returning |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2244 (e.g., doing a long jump to your own recovery point outside Lua). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2245 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2246 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2247 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2248 The panic function runs as if it were a message handler (see <a href="#2.3">§2.3</a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2249 in particular, the error message is at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2250 However, there is no guarantee about stack space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2251 To push anything on the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2252 the panic function must first check the available space (see <a href="#4.2">§4.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2255 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2256 Most functions in the API can raise an error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2257 for instance due to a memory allocation error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2258 The documentation for each function indicates whether |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2259 it can raise errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2260 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2261 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2262 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2263 Inside a C function you can raise an error by calling <a href="#lua_error"><code>lua_error</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2264 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2267 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2268 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2269 <h2>4.7 – <a name="4.7">Handling Yields in C</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2270 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2271 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2272 Internally, Lua uses the C <code>longjmp</code> facility to yield a coroutine. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2273 Therefore, if a C function <code>foo</code> calls an API function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2274 and this API function yields |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2275 (directly or indirectly by calling another function that yields), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2276 Lua cannot return to <code>foo</code> any more, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2277 because the <code>longjmp</code> removes its frame from the C stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2278 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2280 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2281 To avoid this kind of problem, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2282 Lua raises an error whenever it tries to yield across an API call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2283 except for three functions: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2284 <a href="#lua_yieldk"><code>lua_yieldk</code></a>, <a href="#lua_callk"><code>lua_callk</code></a>, and <a href="#lua_pcallk"><code>lua_pcallk</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2285 All those functions receive a <em>continuation function</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2286 (as a parameter named <code>k</code>) to continue execution after a yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2287 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2288 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2289 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2290 We need to set some terminology to explain continuations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2291 We have a C function called from Lua which we will call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2292 the <em>original function</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2293 This original function then calls one of those three functions in the C API, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2294 which we will call the <em>callee function</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2295 that then yields the current thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2296 (This can happen when the callee function is <a href="#lua_yieldk"><code>lua_yieldk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2297 or when the callee function is either <a href="#lua_callk"><code>lua_callk</code></a> or <a href="#lua_pcallk"><code>lua_pcallk</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2298 and the function called by them yields.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2300 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2301 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2302 Suppose the running thread yields while executing the callee function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2303 After the thread resumes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2304 it eventually will finish running the callee function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2305 However, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2306 the callee function cannot return to the original function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2307 because its frame in the C stack was destroyed by the yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2308 Instead, Lua calls a <em>continuation function</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2309 which was given as an argument to the callee function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2310 As the name implies, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2311 the continuation function should continue the task |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2312 of the original function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2313 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2314 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2315 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2316 As an illustration, consider the following function: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2317 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2318 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2319 int original_function (lua_State *L) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2320 ... /* code 1 */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2321 status = lua_pcall(L, n, m, h); /* calls Lua */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2322 ... /* code 2 */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2323 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2324 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2325 Now we want to allow |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2326 the Lua code being run by <a href="#lua_pcall"><code>lua_pcall</code></a> to yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2327 First, we can rewrite our function like here: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2328 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2329 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2330 int k (lua_State *L, int status, lua_KContext ctx) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2331 ... /* code 2 */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2332 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2333 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2334 int original_function (lua_State *L) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2335 ... /* code 1 */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2336 return k(L, lua_pcall(L, n, m, h), ctx); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2337 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2338 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2339 In the above code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2340 the new function <code>k</code> is a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2341 <em>continuation function</em> (with type <a href="#lua_KFunction"><code>lua_KFunction</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2342 which should do all the work that the original function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2343 was doing after calling <a href="#lua_pcall"><code>lua_pcall</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2344 Now, we must inform Lua that it must call <code>k</code> if the Lua code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2345 being executed by <a href="#lua_pcall"><code>lua_pcall</code></a> gets interrupted in some way |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2346 (errors or yielding), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2347 so we rewrite the code as here, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2348 replacing <a href="#lua_pcall"><code>lua_pcall</code></a> by <a href="#lua_pcallk"><code>lua_pcallk</code></a>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2350 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2351 int original_function (lua_State *L) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2352 ... /* code 1 */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2353 return k(L, lua_pcallk(L, n, m, h, ctx2, k), ctx1); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2354 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2355 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2356 Note the external, explicit call to the continuation: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2357 Lua will call the continuation only if needed, that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2358 in case of errors or resuming after a yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2359 If the called function returns normally without ever yielding, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2360 <a href="#lua_pcallk"><code>lua_pcallk</code></a> (and <a href="#lua_callk"><code>lua_callk</code></a>) will also return normally. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2361 (Of course, instead of calling the continuation in that case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2362 you can do the equivalent work directly inside the original function.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2363 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2365 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2366 Besides the Lua state, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2367 the continuation function has two other parameters: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2368 the final status of the call plus the context value (<code>ctx</code>) that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2369 was passed originally to <a href="#lua_pcallk"><code>lua_pcallk</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2370 (Lua does not use this context value; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2371 it only passes this value from the original function to the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2372 continuation function.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2373 For <a href="#lua_pcallk"><code>lua_pcallk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2374 the status is the same value that would be returned by <a href="#lua_pcallk"><code>lua_pcallk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2375 except that it is <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> when being executed after a yield |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2376 (instead of <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2377 For <a href="#lua_yieldk"><code>lua_yieldk</code></a> and <a href="#lua_callk"><code>lua_callk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2378 the status is always <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> when Lua calls the continuation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2379 (For these two functions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2380 Lua will not call the continuation in case of errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2381 because they do not handle errors.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2382 Similarly, when using <a href="#lua_callk"><code>lua_callk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2383 you should call the continuation function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2384 with <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> as the status. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2385 (For <a href="#lua_yieldk"><code>lua_yieldk</code></a>, there is not much point in calling |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2386 directly the continuation function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2387 because <a href="#lua_yieldk"><code>lua_yieldk</code></a> usually does not return.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2388 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2389 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2390 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2391 Lua treats the continuation function as if it were the original function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2392 The continuation function receives the same Lua stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2393 from the original function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2394 in the same state it would be if the callee function had returned. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2395 (For instance, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2396 after a <a href="#lua_callk"><code>lua_callk</code></a> the function and its arguments are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2397 removed from the stack and replaced by the results from the call.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2398 It also has the same upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2399 Whatever it returns is handled by Lua as if it were the return |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2400 of the original function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2403 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2404 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2405 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2406 <h2>4.8 – <a name="4.8">Functions and Types</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2407 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2408 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2409 Here we list all functions and types from the C API in |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2410 alphabetical order. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2411 Each function has an indicator like this: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2412 <span class="apii">[-o, +p, <em>x</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2413 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2414 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2415 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2416 The first field, <code>o</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2417 is how many elements the function pops from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2418 The second field, <code>p</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2419 is how many elements the function pushes onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2420 (Any function always pushes its results after popping its arguments.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2421 A field in the form <code>x|y</code> means the function can push (or pop) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2422 <code>x</code> or <code>y</code> elements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2423 depending on the situation; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2424 an interrogation mark '<code>?</code>' means that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2425 we cannot know how many elements the function pops/pushes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2426 by looking only at its arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2427 (e.g., they may depend on what is on the stack). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2428 The third field, <code>x</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2429 tells whether the function may raise errors: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2430 '<code>-</code>' means the function never raises any error; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2431 '<code>e</code>' means the function may raise errors; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2432 '<code>v</code>' means the function may raise an error on purpose. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2433 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2434 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2435 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2436 <hr><h3><a name="lua_absindex"><code>lua_absindex</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2437 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2438 <pre>int lua_absindex (lua_State *L, int idx);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2439 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2440 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2441 Converts the acceptable index <code>idx</code> into an absolute index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2442 (that is, one that does not depend on the stack top). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2443 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2444 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2445 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2446 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2448 <hr><h3><a name="lua_Alloc"><code>lua_Alloc</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2449 <pre>typedef void * (*lua_Alloc) (void *ud, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2450 void *ptr, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2451 size_t osize, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2452 size_t nsize);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2453 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2454 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2455 The type of the memory-allocation function used by Lua states. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2456 The allocator function must provide a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2457 functionality similar to <code>realloc</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2458 but not exactly the same. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2459 Its arguments are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2460 <code>ud</code>, an opaque pointer passed to <a href="#lua_newstate"><code>lua_newstate</code></a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2461 <code>ptr</code>, a pointer to the block being allocated/reallocated/freed; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2462 <code>osize</code>, the original size of the block or some code about what |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2463 is being allocated; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2464 and <code>nsize</code>, the new size of the block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2465 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2466 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2467 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2468 When <code>ptr</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2469 <code>osize</code> is the size of the block pointed by <code>ptr</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2470 that is, the size given when it was allocated or reallocated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2472 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2473 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2474 When <code>ptr</code> is <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2475 <code>osize</code> encodes the kind of object that Lua is allocating. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2476 <code>osize</code> is any of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2477 <a href="#pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>, <a href="#pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>, <a href="#pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2478 <a href="#pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>, or <a href="#pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a> when (and only when) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2479 Lua is creating a new object of that type. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2480 When <code>osize</code> is some other value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2481 Lua is allocating memory for something else. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2482 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2484 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2485 Lua assumes the following behavior from the allocator function: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2486 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2487 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2488 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2489 When <code>nsize</code> is zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2490 the allocator must behave like <code>free</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2491 and return <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2492 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2493 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2494 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2495 When <code>nsize</code> is not zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2496 the allocator must behave like <code>realloc</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2497 The allocator returns <code>NULL</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2498 if and only if it cannot fulfill the request. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2499 Lua assumes that the allocator never fails when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2500 <code>osize >= nsize</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2501 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2502 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2503 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2504 Here is a simple implementation for the allocator function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2505 It is used in the auxiliary library by <a href="#luaL_newstate"><code>luaL_newstate</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2506 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2507 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2508 static void *l_alloc (void *ud, void *ptr, size_t osize, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2509 size_t nsize) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2510 (void)ud; (void)osize; /* not used */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2511 if (nsize == 0) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2512 free(ptr); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2513 return NULL; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2514 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2515 else |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2516 return realloc(ptr, nsize); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2517 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2518 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2519 Note that Standard C ensures |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2520 that <code>free(NULL)</code> has no effect and that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2521 <code>realloc(NULL,size)</code> is equivalent to <code>malloc(size)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2522 This code assumes that <code>realloc</code> does not fail when shrinking a block. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2523 (Although Standard C does not ensure this behavior, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2524 it seems to be a safe assumption.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2526 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2527 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2528 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2529 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2530 <hr><h3><a name="lua_arith"><code>lua_arith</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2531 <span class="apii">[-(2|1), +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2532 <pre>void lua_arith (lua_State *L, int op);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2533 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2534 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2535 Performs an arithmetic or bitwise operation over the two values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2536 (or one, in the case of negations) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2537 at the top of the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2538 with the value at the top being the second operand, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2539 pops these values, and pushes the result of the operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2540 The function follows the semantics of the corresponding Lua operator |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2541 (that is, it may call metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2542 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2543 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2544 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2545 The value of <code>op</code> must be one of the following constants: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2546 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2547 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2548 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2549 <li><b><a name="pdf-LUA_OPADD"><code>LUA_OPADD</code></a>: </b> performs addition (<code>+</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2550 <li><b><a name="pdf-LUA_OPSUB"><code>LUA_OPSUB</code></a>: </b> performs subtraction (<code>-</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2551 <li><b><a name="pdf-LUA_OPMUL"><code>LUA_OPMUL</code></a>: </b> performs multiplication (<code>*</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2552 <li><b><a name="pdf-LUA_OPDIV"><code>LUA_OPDIV</code></a>: </b> performs float division (<code>/</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2553 <li><b><a name="pdf-LUA_OPIDIV"><code>LUA_OPIDIV</code></a>: </b> performs floor division (<code>//</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2554 <li><b><a name="pdf-LUA_OPMOD"><code>LUA_OPMOD</code></a>: </b> performs modulo (<code>%</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2555 <li><b><a name="pdf-LUA_OPPOW"><code>LUA_OPPOW</code></a>: </b> performs exponentiation (<code>^</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2556 <li><b><a name="pdf-LUA_OPUNM"><code>LUA_OPUNM</code></a>: </b> performs mathematical negation (unary <code>-</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2557 <li><b><a name="pdf-LUA_OPBNOT"><code>LUA_OPBNOT</code></a>: </b> performs bitwise negation (<code>~</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2558 <li><b><a name="pdf-LUA_OPBAND"><code>LUA_OPBAND</code></a>: </b> performs bitwise and (<code>&</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2559 <li><b><a name="pdf-LUA_OPBOR"><code>LUA_OPBOR</code></a>: </b> performs bitwise or (<code>|</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2560 <li><b><a name="pdf-LUA_OPBXOR"><code>LUA_OPBXOR</code></a>: </b> performs bitwise exclusive or (<code>~</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2561 <li><b><a name="pdf-LUA_OPSHL"><code>LUA_OPSHL</code></a>: </b> performs left shift (<code><<</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2562 <li><b><a name="pdf-LUA_OPSHR"><code>LUA_OPSHR</code></a>: </b> performs right shift (<code>>></code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2563 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2564 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2566 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2567 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2568 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2569 <hr><h3><a name="lua_atpanic"><code>lua_atpanic</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2570 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2571 <pre>lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2572 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2573 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2574 Sets a new panic function and returns the old one (see <a href="#4.6">§4.6</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2575 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2576 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2577 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2578 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2579 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2580 <hr><h3><a name="lua_call"><code>lua_call</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2581 <span class="apii">[-(nargs+1), +nresults, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2582 <pre>void lua_call (lua_State *L, int nargs, int nresults);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2583 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2584 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2585 Calls a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2586 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2587 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2588 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2589 To call a function you must use the following protocol: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2590 first, the function to be called is pushed onto the stack; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2591 then, the arguments to the function are pushed |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2592 in direct order; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2593 that is, the first argument is pushed first. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2594 Finally you call <a href="#lua_call"><code>lua_call</code></a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2595 <code>nargs</code> is the number of arguments that you pushed onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2596 All arguments and the function value are popped from the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2597 when the function is called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2598 The function results are pushed onto the stack when the function returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2599 The number of results is adjusted to <code>nresults</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2600 unless <code>nresults</code> is <a name="pdf-LUA_MULTRET"><code>LUA_MULTRET</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2601 In this case, all results from the function are pushed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2602 Lua takes care that the returned values fit into the stack space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2603 The function results are pushed onto the stack in direct order |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2604 (the first result is pushed first), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2605 so that after the call the last result is on the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2607 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2608 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2609 Any error inside the called function is propagated upwards |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2610 (with a <code>longjmp</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2611 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2612 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2613 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2614 The following example shows how the host program can do the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2615 equivalent to this Lua code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2616 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2617 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2618 a = f("how", t.x, 14) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2619 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2620 Here it is in C: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2621 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2622 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2623 lua_getglobal(L, "f"); /* function to be called */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2624 lua_pushliteral(L, "how"); /* 1st argument */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2625 lua_getglobal(L, "t"); /* table to be indexed */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2626 lua_getfield(L, -1, "x"); /* push result of t.x (2nd arg) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2627 lua_remove(L, -2); /* remove 't' from the stack */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2628 lua_pushinteger(L, 14); /* 3rd argument */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2629 lua_call(L, 3, 1); /* call 'f' with 3 arguments and 1 result */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2630 lua_setglobal(L, "a"); /* set global 'a' */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2631 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2632 Note that the code above is <em>balanced</em>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2633 at its end, the stack is back to its original configuration. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2634 This is considered good programming practice. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2635 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2636 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2637 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2638 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2639 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2640 <hr><h3><a name="lua_callk"><code>lua_callk</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2641 <span class="apii">[-(nargs + 1), +nresults, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2642 <pre>void lua_callk (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2643 int nargs, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2644 int nresults, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2645 lua_KContext ctx, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2646 lua_KFunction k);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2648 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2649 This function behaves exactly like <a href="#lua_call"><code>lua_call</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2650 but allows the called function to yield (see <a href="#4.7">§4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2651 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2652 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2653 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2654 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2655 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2656 <hr><h3><a name="lua_CFunction"><code>lua_CFunction</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2657 <pre>typedef int (*lua_CFunction) (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2658 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2659 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2660 Type for C functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2661 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2663 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2664 In order to communicate properly with Lua, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2665 a C function must use the following protocol, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2666 which defines the way parameters and results are passed: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2667 a C function receives its arguments from Lua in its stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2668 in direct order (the first argument is pushed first). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2669 So, when the function starts, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2670 <code>lua_gettop(L)</code> returns the number of arguments received by the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2671 The first argument (if any) is at index 1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2672 and its last argument is at index <code>lua_gettop(L)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2673 To return values to Lua, a C function just pushes them onto the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2674 in direct order (the first result is pushed first), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2675 and returns the number of results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2676 Any other value in the stack below the results will be properly |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2677 discarded by Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2678 Like a Lua function, a C function called by Lua can also return |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2679 many results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2680 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2681 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2682 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2683 As an example, the following function receives a variable number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2684 of numerical arguments and returns their average and their sum: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2685 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2686 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2687 static int foo (lua_State *L) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2688 int n = lua_gettop(L); /* number of arguments */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2689 lua_Number sum = 0.0; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2690 int i; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2691 for (i = 1; i <= n; i++) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2692 if (!lua_isnumber(L, i)) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2693 lua_pushliteral(L, "incorrect argument"); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2694 lua_error(L); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2695 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2696 sum += lua_tonumber(L, i); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2697 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2698 lua_pushnumber(L, sum/n); /* first result */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2699 lua_pushnumber(L, sum); /* second result */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2700 return 2; /* number of results */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2701 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2702 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2703 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2704 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2705 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2706 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2707 <hr><h3><a name="lua_checkstack"><code>lua_checkstack</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2708 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2709 <pre>int lua_checkstack (lua_State *L, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2710 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2711 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2712 Ensures that the stack has space for at least <code>n</code> extra slots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2713 It returns false if it cannot fulfill the request, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2714 either because it would cause the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2715 to be larger than a fixed maximum size |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2716 (typically at least several thousand elements) or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2717 because it cannot allocate memory for the extra space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2718 This function never shrinks the stack; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2719 if the stack is already larger than the new size, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2720 it is left unchanged. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2721 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2722 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2723 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2726 <hr><h3><a name="lua_close"><code>lua_close</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2727 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2728 <pre>void lua_close (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2729 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2730 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2731 Destroys all objects in the given Lua state |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2732 (calling the corresponding garbage-collection metamethods, if any) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2733 and frees all dynamic memory used by this state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2734 On several platforms, you may not need to call this function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2735 because all resources are naturally released when the host program ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2736 On the other hand, long-running programs that create multiple states, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2737 such as daemons or web servers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2738 will probably need to close states as soon as they are not needed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2739 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2740 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2741 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2742 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2743 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2744 <hr><h3><a name="lua_compare"><code>lua_compare</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2745 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2746 <pre>int lua_compare (lua_State *L, int index1, int index2, int op);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2747 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2748 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2749 Compares two Lua values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2750 Returns 1 if the value at index <code>index1</code> satisfies <code>op</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2751 when compared with the value at index <code>index2</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2752 following the semantics of the corresponding Lua operator |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2753 (that is, it may call metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2754 Otherwise returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2755 Also returns 0 if any of the indices is not valid. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2756 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2757 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2758 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2759 The value of <code>op</code> must be one of the following constants: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2760 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2761 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2762 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2763 <li><b><a name="pdf-LUA_OPEQ"><code>LUA_OPEQ</code></a>: </b> compares for equality (<code>==</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2764 <li><b><a name="pdf-LUA_OPLT"><code>LUA_OPLT</code></a>: </b> compares for less than (<code><</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2765 <li><b><a name="pdf-LUA_OPLE"><code>LUA_OPLE</code></a>: </b> compares for less or equal (<code><=</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2766 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2767 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2768 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2769 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2770 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2771 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2772 <hr><h3><a name="lua_concat"><code>lua_concat</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2773 <span class="apii">[-n, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2774 <pre>void lua_concat (lua_State *L, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2775 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2776 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2777 Concatenates the <code>n</code> values at the top of the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2778 pops them, and leaves the result at the top. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2779 If <code>n</code> is 1, the result is the single value on the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2780 (that is, the function does nothing); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2781 if <code>n</code> is 0, the result is the empty string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2782 Concatenation is performed following the usual semantics of Lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2783 (see <a href="#3.4.6">§3.4.6</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2784 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2785 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2786 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2787 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2788 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2789 <hr><h3><a name="lua_copy"><code>lua_copy</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2790 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2791 <pre>void lua_copy (lua_State *L, int fromidx, int toidx);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2792 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2793 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2794 Copies the element at index <code>fromidx</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2795 into the valid index <code>toidx</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2796 replacing the value at that position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2797 Values at other positions are not affected. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2798 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2799 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2800 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2802 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2803 <hr><h3><a name="lua_createtable"><code>lua_createtable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2804 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2805 <pre>void lua_createtable (lua_State *L, int narr, int nrec);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2807 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2808 Creates a new empty table and pushes it onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2809 Parameter <code>narr</code> is a hint for how many elements the table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2810 will have as a sequence; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2811 parameter <code>nrec</code> is a hint for how many other elements |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2812 the table will have. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2813 Lua may use these hints to preallocate memory for the new table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2814 This pre-allocation is useful for performance when you know in advance |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2815 how many elements the table will have. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2816 Otherwise you can use the function <a href="#lua_newtable"><code>lua_newtable</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2817 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2818 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2819 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2822 <hr><h3><a name="lua_dump"><code>lua_dump</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2823 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2824 <pre>int lua_dump (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2825 lua_Writer writer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2826 void *data, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2827 int strip);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2828 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2829 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2830 Dumps a function as a binary chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2831 Receives a Lua function on the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2832 and produces a binary chunk that, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2833 if loaded again, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2834 results in a function equivalent to the one dumped. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2835 As it produces parts of the chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2836 <a href="#lua_dump"><code>lua_dump</code></a> calls function <code>writer</code> (see <a href="#lua_Writer"><code>lua_Writer</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2837 with the given <code>data</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2838 to write them. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2839 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2840 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2841 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2842 If <code>strip</code> is true, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2843 the binary representation is created without debug information |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2844 about the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2845 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2846 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2847 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2848 The value returned is the error code returned by the last |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2849 call to the writer; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2850 0 means no errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2851 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2852 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2853 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2854 This function does not pop the Lua function from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2855 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2856 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2857 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2858 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2859 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2860 <hr><h3><a name="lua_error"><code>lua_error</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2861 <span class="apii">[-1, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2862 <pre>int lua_error (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2863 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2864 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2865 Generates a Lua error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2866 using the value at the top of the stack as the error object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2867 This function does a long jump, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2868 and therefore never returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2869 (see <a href="#luaL_error"><code>luaL_error</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2870 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2871 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2872 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2873 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2874 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2875 <hr><h3><a name="lua_gc"><code>lua_gc</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2876 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2877 <pre>int lua_gc (lua_State *L, int what, int data);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2878 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2879 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2880 Controls the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2881 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2882 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2883 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2884 This function performs several tasks, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2885 according to the value of the parameter <code>what</code>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2886 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2887 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2888 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2889 <li><b><code>LUA_GCSTOP</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2890 stops the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2891 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2892 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2893 <li><b><code>LUA_GCRESTART</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2894 restarts the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2895 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2896 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2897 <li><b><code>LUA_GCCOLLECT</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2898 performs a full garbage-collection cycle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2899 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2900 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2901 <li><b><code>LUA_GCCOUNT</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2902 returns the current amount of memory (in Kbytes) in use by Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2903 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2904 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2905 <li><b><code>LUA_GCCOUNTB</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2906 returns the remainder of dividing the current amount of bytes of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2907 memory in use by Lua by 1024. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2908 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2909 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2910 <li><b><code>LUA_GCSTEP</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2911 performs an incremental step of garbage collection. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2912 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2913 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2914 <li><b><code>LUA_GCSETPAUSE</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2915 sets <code>data</code> as the new value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2916 for the <em>pause</em> of the collector (see <a href="#2.5">§2.5</a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2917 and returns the previous value of the pause. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2918 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2919 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2920 <li><b><code>LUA_GCSETSTEPMUL</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2921 sets <code>data</code> as the new value for the <em>step multiplier</em> of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2922 the collector (see <a href="#2.5">§2.5</a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2923 and returns the previous value of the step multiplier. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2924 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2925 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2926 <li><b><code>LUA_GCISRUNNING</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2927 returns a boolean that tells whether the collector is running |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2928 (i.e., not stopped). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2929 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2930 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2931 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2933 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2934 For more details about these options, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2935 see <a href="#pdf-collectgarbage"><code>collectgarbage</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2937 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2938 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2939 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2941 <hr><h3><a name="lua_getallocf"><code>lua_getallocf</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2942 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2943 <pre>lua_Alloc lua_getallocf (lua_State *L, void **ud);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2944 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2945 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2946 Returns the memory-allocation function of a given state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2947 If <code>ud</code> is not <code>NULL</code>, Lua stores in <code>*ud</code> the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2948 opaque pointer given when the memory-allocator function was set. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2949 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2950 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2951 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2952 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2953 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2954 <hr><h3><a name="lua_getfield"><code>lua_getfield</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2955 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2956 <pre>int lua_getfield (lua_State *L, int index, const char *k);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2957 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2958 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2959 Pushes onto the stack the value <code>t[k]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2960 where <code>t</code> is the value at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2961 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2962 for the "index" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2964 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2965 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2966 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2967 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2968 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2969 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2970 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2971 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2972 <hr><h3><a name="lua_getextraspace"><code>lua_getextraspace</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2973 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2974 <pre>void *lua_getextraspace (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2975 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2976 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2977 Returns a pointer to a raw memory area associated with the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2978 given Lua state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2979 The application can use this area for any purpose; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2980 Lua does not use it for anything. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2981 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2982 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2983 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2984 Each new thread has this area initialized with a copy |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2985 of the area of the main thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2986 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2987 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2988 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2989 By default, this area has the size of a pointer to void, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2990 but you can recompile Lua with a different size for this area. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2991 (See <code>LUA_EXTRASPACE</code> in <code>luaconf.h</code>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2992 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2995 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2996 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2997 <hr><h3><a name="lua_getglobal"><code>lua_getglobal</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2998 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
2999 <pre>int lua_getglobal (lua_State *L, const char *name);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3000 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3001 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3002 Pushes onto the stack the value of the global <code>name</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3003 Returns the type of that value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3006 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3007 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3008 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3009 <hr><h3><a name="lua_geti"><code>lua_geti</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3010 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3011 <pre>int lua_geti (lua_State *L, int index, lua_Integer i);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3012 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3013 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3014 Pushes onto the stack the value <code>t[i]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3015 where <code>t</code> is the value at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3016 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3017 for the "index" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3019 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3020 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3021 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3022 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3023 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3024 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3025 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3026 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3027 <hr><h3><a name="lua_getmetatable"><code>lua_getmetatable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3028 <span class="apii">[-0, +(0|1), –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3029 <pre>int lua_getmetatable (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3030 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3031 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3032 If the value at the given index has a metatable, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3033 the function pushes that metatable onto the stack and returns 1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3034 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3035 the function returns 0 and pushes nothing on the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3036 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3037 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3038 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3039 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3040 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3041 <hr><h3><a name="lua_gettable"><code>lua_gettable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3042 <span class="apii">[-1, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3043 <pre>int lua_gettable (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3044 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3045 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3046 Pushes onto the stack the value <code>t[k]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3047 where <code>t</code> is the value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3048 and <code>k</code> is the value at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3049 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3051 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3052 This function pops the key from the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3053 pushing the resulting value in its place. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3054 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3055 for the "index" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3057 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3058 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3059 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3060 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3061 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3062 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3063 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3064 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3065 <hr><h3><a name="lua_gettop"><code>lua_gettop</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3066 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3067 <pre>int lua_gettop (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3068 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3069 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3070 Returns the index of the top element in the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3071 Because indices start at 1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3072 this result is equal to the number of elements in the stack; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3073 in particular, 0 means an empty stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3074 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3075 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3076 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3077 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3078 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3079 <hr><h3><a name="lua_getuservalue"><code>lua_getuservalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3080 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3081 <pre>int lua_getuservalue (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3083 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3084 Pushes onto the stack the Lua value associated with the userdata |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3085 at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3086 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3087 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3088 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3089 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3090 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3091 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3092 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3093 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3094 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3095 <hr><h3><a name="lua_insert"><code>lua_insert</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3096 <span class="apii">[-1, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3097 <pre>void lua_insert (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3099 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3100 Moves the top element into the given valid index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3101 shifting up the elements above this index to open space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3102 This function cannot be called with a pseudo-index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3103 because a pseudo-index is not an actual stack position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3104 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3105 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3106 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3109 <hr><h3><a name="lua_Integer"><code>lua_Integer</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3110 <pre>typedef ... lua_Integer;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3111 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3112 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3113 The type of integers in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3114 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3115 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3116 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3117 By default this type is <code>long long</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3118 (usually a 64-bit two-complement integer), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3119 but that can be changed to <code>long</code> or <code>int</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3120 (usually a 32-bit two-complement integer). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3121 (See <code>LUA_INT</code> in <code>luaconf.h</code>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3122 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3123 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3124 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3125 Lua also defines the constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3126 <a name="pdf-LUA_MININTEGER"><code>LUA_MININTEGER</code></a> and <a name="pdf-LUA_MAXINTEGER"><code>LUA_MAXINTEGER</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3127 with the minimum and the maximum values that fit in this type. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3128 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3129 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3130 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3131 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3132 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3133 <hr><h3><a name="lua_isboolean"><code>lua_isboolean</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3134 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3135 <pre>int lua_isboolean (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3136 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3137 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3138 Returns 1 if the value at the given index is a boolean, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3139 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3140 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3144 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3145 <hr><h3><a name="lua_iscfunction"><code>lua_iscfunction</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3146 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3147 <pre>int lua_iscfunction (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3148 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3149 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3150 Returns 1 if the value at the given index is a C function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3151 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3152 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3153 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3154 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3156 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3157 <hr><h3><a name="lua_isfunction"><code>lua_isfunction</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3158 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3159 <pre>int lua_isfunction (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3160 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3161 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3162 Returns 1 if the value at the given index is a function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3163 (either C or Lua), and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3164 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3165 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3166 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3169 <hr><h3><a name="lua_isinteger"><code>lua_isinteger</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3170 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3171 <pre>int lua_isinteger (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3172 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3173 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3174 Returns 1 if the value at the given index is an integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3175 (that is, the value is a number and is represented as an integer), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3176 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3177 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3178 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3179 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3180 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3182 <hr><h3><a name="lua_islightuserdata"><code>lua_islightuserdata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3183 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3184 <pre>int lua_islightuserdata (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3185 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3186 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3187 Returns 1 if the value at the given index is a light userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3188 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3190 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3191 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3192 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3193 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3194 <hr><h3><a name="lua_isnil"><code>lua_isnil</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3195 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3196 <pre>int lua_isnil (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3198 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3199 Returns 1 if the value at the given index is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3200 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3202 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3203 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3204 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3206 <hr><h3><a name="lua_isnone"><code>lua_isnone</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3207 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3208 <pre>int lua_isnone (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3210 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3211 Returns 1 if the given index is not valid, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3212 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3214 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3215 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3216 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3218 <hr><h3><a name="lua_isnoneornil"><code>lua_isnoneornil</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3219 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3220 <pre>int lua_isnoneornil (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3221 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3222 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3223 Returns 1 if the given index is not valid |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3224 or if the value at this index is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3225 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3226 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3227 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3228 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3229 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3230 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3231 <hr><h3><a name="lua_isnumber"><code>lua_isnumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3232 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3233 <pre>int lua_isnumber (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3234 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3235 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3236 Returns 1 if the value at the given index is a number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3237 or a string convertible to a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3238 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3239 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3240 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3243 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3244 <hr><h3><a name="lua_isstring"><code>lua_isstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3245 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3246 <pre>int lua_isstring (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3247 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3248 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3249 Returns 1 if the value at the given index is a string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3250 or a number (which is always convertible to a string), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3251 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3252 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3255 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3256 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3257 <hr><h3><a name="lua_istable"><code>lua_istable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3258 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3259 <pre>int lua_istable (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3260 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3261 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3262 Returns 1 if the value at the given index is a table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3263 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3264 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3267 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3268 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3269 <hr><h3><a name="lua_isthread"><code>lua_isthread</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3270 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3271 <pre>int lua_isthread (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3272 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3273 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3274 Returns 1 if the value at the given index is a thread, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3275 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3276 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3277 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3278 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3280 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3281 <hr><h3><a name="lua_isuserdata"><code>lua_isuserdata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3282 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3283 <pre>int lua_isuserdata (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3284 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3285 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3286 Returns 1 if the value at the given index is a userdata |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3287 (either full or light), and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3288 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3289 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3290 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3291 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3292 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3293 <hr><h3><a name="lua_isyieldable"><code>lua_isyieldable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3294 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3295 <pre>int lua_isyieldable (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3296 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3297 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3298 Returns 1 if the given coroutine can yield, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3299 and 0 otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3300 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3301 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3302 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3303 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3304 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3305 <hr><h3><a name="lua_KContext"><code>lua_KContext</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3306 <pre>typedef ... lua_KContext;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3307 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3308 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3309 The type for continuation-function contexts. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3310 It must be a numerical type. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3311 This type is defined as <code>intptr_t</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3312 when <code>intptr_t</code> is available, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3313 so that it can store pointers too. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3314 Otherwise, it is defined as <code>ptrdiff_t</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3315 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3316 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3317 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3318 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3319 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3320 <hr><h3><a name="lua_KFunction"><code>lua_KFunction</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3321 <pre>typedef int (*lua_KFunction) (lua_State *L, int status, lua_KContext ctx);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3322 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3323 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3324 Type for continuation functions (see <a href="#4.7">§4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3325 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3326 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3327 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3328 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3329 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3330 <hr><h3><a name="lua_len"><code>lua_len</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3331 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3332 <pre>void lua_len (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3333 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3334 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3335 Returns the length of the value at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3336 It is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.7">§3.4.7</a>) and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3337 may trigger a metamethod for the "length" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3338 The result is pushed on the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3339 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3340 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3341 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3342 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3343 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3344 <hr><h3><a name="lua_load"><code>lua_load</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3345 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3346 <pre>int lua_load (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3347 lua_Reader reader, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3348 void *data, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3349 const char *chunkname, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3350 const char *mode);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3351 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3352 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3353 Loads a Lua chunk without running it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3354 If there are no errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3355 <code>lua_load</code> pushes the compiled chunk as a Lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3356 function on top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3357 Otherwise, it pushes an error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3358 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3359 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3360 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3361 The return values of <code>lua_load</code> are: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3362 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3363 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3365 <li><b><a href="#pdf-LUA_OK"><code>LUA_OK</code></a>: </b> no errors;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3366 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3367 <li><b><a name="pdf-LUA_ERRSYNTAX"><code>LUA_ERRSYNTAX</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3368 syntax error during precompilation;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3369 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3370 <li><b><a href="#pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3371 memory allocation error;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3372 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3373 <li><b><a href="#pdf-LUA_ERRGCMM"><code>LUA_ERRGCMM</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3374 error while running a <code>__gc</code> metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3375 (This error has no relation with the chunk being loaded. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3376 It is generated by the garbage collector.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3377 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3378 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3379 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3380 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3381 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3382 The <code>lua_load</code> function uses a user-supplied <code>reader</code> function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3383 to read the chunk (see <a href="#lua_Reader"><code>lua_Reader</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3384 The <code>data</code> argument is an opaque value passed to the reader function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3385 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3387 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3388 The <code>chunkname</code> argument gives a name to the chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3389 which is used for error messages and in debug information (see <a href="#4.9">§4.9</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3390 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3391 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3392 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3393 <code>lua_load</code> automatically detects whether the chunk is text or binary |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3394 and loads it accordingly (see program <code>luac</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3395 The string <code>mode</code> works as in function <a href="#pdf-load"><code>load</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3396 with the addition that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3397 a <code>NULL</code> value is equivalent to the string "<code>bt</code>". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3398 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3399 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3400 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3401 <code>lua_load</code> uses the stack internally, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3402 so the reader function must always leave the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3403 unmodified when returning. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3404 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3405 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3406 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3407 If the resulting function has upvalues, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3408 its first upvalue is set to the value of the global environment |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3409 stored at index <code>LUA_RIDX_GLOBALS</code> in the registry (see <a href="#4.5">§4.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3410 When loading main chunks, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3411 this upvalue will be the <code>_ENV</code> variable (see <a href="#2.2">§2.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3412 Other upvalues are initialized with <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3413 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3414 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3415 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3416 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3418 <hr><h3><a name="lua_newstate"><code>lua_newstate</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3419 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3420 <pre>lua_State *lua_newstate (lua_Alloc f, void *ud);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3421 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3422 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3423 Creates a new thread running in a new, independent state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3424 Returns <code>NULL</code> if it cannot create the thread or the state |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3425 (due to lack of memory). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3426 The argument <code>f</code> is the allocator function; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3427 Lua does all memory allocation for this state through this function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3428 The second argument, <code>ud</code>, is an opaque pointer that Lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3429 passes to the allocator in every call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3430 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3431 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3432 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3433 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3434 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3435 <hr><h3><a name="lua_newtable"><code>lua_newtable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3436 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3437 <pre>void lua_newtable (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3438 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3439 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3440 Creates a new empty table and pushes it onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3441 It is equivalent to <code>lua_createtable(L, 0, 0)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3443 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3444 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3445 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3446 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3447 <hr><h3><a name="lua_newthread"><code>lua_newthread</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3448 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3449 <pre>lua_State *lua_newthread (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3450 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3451 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3452 Creates a new thread, pushes it on the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3453 and returns a pointer to a <a href="#lua_State"><code>lua_State</code></a> that represents this new thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3454 The new thread returned by this function shares with the original thread |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3455 its global environment, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3456 but has an independent execution stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3457 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3458 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3459 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3460 There is no explicit function to close or to destroy a thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3461 Threads are subject to garbage collection, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3462 like any Lua object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3463 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3464 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3465 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3466 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3467 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3468 <hr><h3><a name="lua_newuserdata"><code>lua_newuserdata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3469 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3470 <pre>void *lua_newuserdata (lua_State *L, size_t size);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3472 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3473 This function allocates a new block of memory with the given size, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3474 pushes onto the stack a new full userdata with the block address, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3475 and returns this address. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3476 The host program can freely use this memory. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3477 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3478 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3479 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3480 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3481 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3482 <hr><h3><a name="lua_next"><code>lua_next</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3483 <span class="apii">[-1, +(2|0), <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3484 <pre>int lua_next (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3485 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3486 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3487 Pops a key from the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3488 and pushes a key–value pair from the table at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3489 (the "next" pair after the given key). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3490 If there are no more elements in the table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3491 then <a href="#lua_next"><code>lua_next</code></a> returns 0 (and pushes nothing). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3492 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3493 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3494 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3495 A typical traversal looks like this: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3496 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3497 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3498 /* table is in the stack at index 't' */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3499 lua_pushnil(L); /* first key */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3500 while (lua_next(L, t) != 0) { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3501 /* uses 'key' (at index -2) and 'value' (at index -1) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3502 printf("%s - %s\n", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3503 lua_typename(L, lua_type(L, -2)), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3504 lua_typename(L, lua_type(L, -1))); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3505 /* removes 'value'; keeps 'key' for next iteration */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3506 lua_pop(L, 1); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3507 } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3508 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3509 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3510 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3511 While traversing a table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3512 do not call <a href="#lua_tolstring"><code>lua_tolstring</code></a> directly on a key, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3513 unless you know that the key is actually a string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3514 Recall that <a href="#lua_tolstring"><code>lua_tolstring</code></a> may change |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3515 the value at the given index; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3516 this confuses the next call to <a href="#lua_next"><code>lua_next</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3517 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3518 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3519 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3520 See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3521 the table during its traversal. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3522 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3523 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3524 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3526 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3527 <hr><h3><a name="lua_Number"><code>lua_Number</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3528 <pre>typedef double lua_Number;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3529 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3530 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3531 The type of floats in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3532 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3533 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3534 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3535 By default this type is double, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3536 but that can be changed to a single float. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3537 (See <code>LUA_REAL</code> in <code>luaconf.h</code>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3540 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3541 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3542 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3543 <hr><h3><a name="lua_numbertointeger"><code>lua_numbertointeger</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3544 <pre>int lua_numbertointeger (lua_Number n, lua_Integer *p);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3545 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3546 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3547 Converts a Lua float to a Lua integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3548 This macro assumes that <code>n</code> has an integral value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3549 If that value is within the range of Lua integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3550 it is converted to an integer and assigned to <code>*p</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3551 The macro results in a boolean indicating whether the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3552 conversion was successful. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3553 (Note that this range test can be tricky to do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3554 correctly without this macro, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3555 due to roundings.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3556 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3557 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3558 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3559 This macro may evaluate its arguments more than once. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3561 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3562 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3563 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3564 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3565 <hr><h3><a name="lua_pcall"><code>lua_pcall</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3566 <span class="apii">[-(nargs + 1), +(nresults|1), –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3567 <pre>int lua_pcall (lua_State *L, int nargs, int nresults, int msgh);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3568 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3569 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3570 Calls a function in protected mode. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3571 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3572 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3573 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3574 Both <code>nargs</code> and <code>nresults</code> have the same meaning as |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3575 in <a href="#lua_call"><code>lua_call</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3576 If there are no errors during the call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3577 <a href="#lua_pcall"><code>lua_pcall</code></a> behaves exactly like <a href="#lua_call"><code>lua_call</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3578 However, if there is any error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3579 <a href="#lua_pcall"><code>lua_pcall</code></a> catches it, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3580 pushes a single value on the stack (the error message), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3581 and returns an error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3582 Like <a href="#lua_call"><code>lua_call</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3583 <a href="#lua_pcall"><code>lua_pcall</code></a> always removes the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3584 and its arguments from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3585 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3586 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3587 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3588 If <code>msgh</code> is 0, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3589 then the error message returned on the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3590 is exactly the original error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3591 Otherwise, <code>msgh</code> is the stack index of a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3592 <em>message handler</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3593 (In the current implementation, this index cannot be a pseudo-index.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3594 In case of runtime errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3595 this function will be called with the error message |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3596 and its return value will be the message |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3597 returned on the stack by <a href="#lua_pcall"><code>lua_pcall</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3598 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3599 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3600 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3601 Typically, the message handler is used to add more debug |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3602 information to the error message, such as a stack traceback. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3603 Such information cannot be gathered after the return of <a href="#lua_pcall"><code>lua_pcall</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3604 since by then the stack has unwound. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3605 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3607 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3608 The <a href="#lua_pcall"><code>lua_pcall</code></a> function returns one of the following constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3609 (defined in <code>lua.h</code>): |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3610 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3611 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3612 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3613 <li><b><a name="pdf-LUA_OK"><code>LUA_OK</code></a> (0): </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3614 success.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3615 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3616 <li><b><a name="pdf-LUA_ERRRUN"><code>LUA_ERRRUN</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3617 a runtime error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3618 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3619 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3620 <li><b><a name="pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3621 memory allocation error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3622 For such errors, Lua does not call the message handler. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3623 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3624 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3625 <li><b><a name="pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3626 error while running the message handler. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3627 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3628 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3629 <li><b><a name="pdf-LUA_ERRGCMM"><code>LUA_ERRGCMM</code></a>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3630 error while running a <code>__gc</code> metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3631 (This error typically has no relation with the function being called.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3632 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3633 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3634 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3635 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3636 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3637 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3638 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3639 <hr><h3><a name="lua_pcallk"><code>lua_pcallk</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3640 <span class="apii">[-(nargs + 1), +(nresults|1), –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3641 <pre>int lua_pcallk (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3642 int nargs, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3643 int nresults, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3644 int msgh, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3645 lua_KContext ctx, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3646 lua_KFunction k);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3648 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3649 This function behaves exactly like <a href="#lua_pcall"><code>lua_pcall</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3650 but allows the called function to yield (see <a href="#4.7">§4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3651 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3652 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3653 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3654 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3655 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3656 <hr><h3><a name="lua_pop"><code>lua_pop</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3657 <span class="apii">[-n, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3658 <pre>void lua_pop (lua_State *L, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3659 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3660 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3661 Pops <code>n</code> elements from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3663 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3664 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3665 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3666 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3667 <hr><h3><a name="lua_pushboolean"><code>lua_pushboolean</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3668 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3669 <pre>void lua_pushboolean (lua_State *L, int b);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3670 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3671 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3672 Pushes a boolean value with value <code>b</code> onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3673 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3674 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3675 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3676 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3677 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3678 <hr><h3><a name="lua_pushcclosure"><code>lua_pushcclosure</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3679 <span class="apii">[-n, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3680 <pre>void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3681 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3682 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3683 Pushes a new C closure onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3684 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3685 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3686 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3687 When a C function is created, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3688 it is possible to associate some values with it, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3689 thus creating a C closure (see <a href="#4.4">§4.4</a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3690 these values are then accessible to the function whenever it is called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3691 To associate values with a C function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3692 first these values must be pushed onto the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3693 (when there are multiple values, the first value is pushed first). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3694 Then <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3695 is called to create and push the C function onto the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3696 with the argument <code>n</code> telling how many values will be |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3697 associated with the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3698 <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a> also pops these values from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3699 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3700 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3701 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3702 The maximum value for <code>n</code> is 255. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3703 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3704 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3705 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3706 When <code>n</code> is zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3707 this function creates a <em>light C function</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3708 which is just a pointer to the C function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3709 In that case, it never raises a memory error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3710 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3711 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3712 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3713 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3714 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3715 <hr><h3><a name="lua_pushcfunction"><code>lua_pushcfunction</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3716 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3717 <pre>void lua_pushcfunction (lua_State *L, lua_CFunction f);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3718 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3719 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3720 Pushes a C function onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3721 This function receives a pointer to a C function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3722 and pushes onto the stack a Lua value of type <code>function</code> that, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3723 when called, invokes the corresponding C function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3726 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3727 Any function to be registered in Lua must |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3728 follow the correct protocol to receive its parameters |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3729 and return its results (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3730 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3731 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3732 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3733 <code>lua_pushcfunction</code> is defined as a macro: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3734 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3735 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3736 #define lua_pushcfunction(L,f) lua_pushcclosure(L,f,0) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3737 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3738 Note that <code>f</code> is used twice. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3739 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3740 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3741 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3742 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3743 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3744 <hr><h3><a name="lua_pushfstring"><code>lua_pushfstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3745 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3746 <pre>const char *lua_pushfstring (lua_State *L, const char *fmt, ...);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3747 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3748 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3749 Pushes onto the stack a formatted string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3750 and returns a pointer to this string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3751 It is similar to the ISO C function <code>sprintf</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3752 but has some important differences: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3754 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3755 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3756 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3757 You do not have to allocate space for the result: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3758 the result is a Lua string and Lua takes care of memory allocation |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3759 (and deallocation, through garbage collection). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3760 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3761 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3762 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3763 The conversion specifiers are quite restricted. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3764 There are no flags, widths, or precisions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3765 The conversion specifiers can only be |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3766 '<code>%%</code>' (inserts the character '<code>%</code>'), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3767 '<code>%s</code>' (inserts a zero-terminated string, with no size restrictions), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3768 '<code>%f</code>' (inserts a <a href="#lua_Number"><code>lua_Number</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3769 '<code>%L</code>' (inserts a <a href="#lua_Integer"><code>lua_Integer</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3770 '<code>%p</code>' (inserts a pointer as a hexadecimal numeral), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3771 '<code>%d</code>' (inserts an <code>int</code>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3772 '<code>%c</code>' (inserts an <code>int</code> as a one-byte character), and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3773 '<code>%U</code>' (inserts a <code>long int</code> as a UTF-8 byte sequence). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3774 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3775 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3776 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3777 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3778 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3779 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3780 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3781 <hr><h3><a name="lua_pushglobaltable"><code>lua_pushglobaltable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3782 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3783 <pre>void lua_pushglobaltable (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3784 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3785 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3786 Pushes the global environment onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3787 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3788 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3789 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3790 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3792 <hr><h3><a name="lua_pushinteger"><code>lua_pushinteger</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3793 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3794 <pre>void lua_pushinteger (lua_State *L, lua_Integer n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3795 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3796 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3797 Pushes an integer with value <code>n</code> onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3798 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3799 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3800 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3802 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3803 <hr><h3><a name="lua_pushlightuserdata"><code>lua_pushlightuserdata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3804 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3805 <pre>void lua_pushlightuserdata (lua_State *L, void *p);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3807 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3808 Pushes a light userdata onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3810 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3811 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3812 Userdata represent C values in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3813 A <em>light userdata</em> represents a pointer, a <code>void*</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3814 It is a value (like a number): |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3815 you do not create it, it has no individual metatable, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3816 and it is not collected (as it was never created). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3817 A light userdata is equal to "any" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3818 light userdata with the same C address. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3819 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3822 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3823 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3824 <hr><h3><a name="lua_pushliteral"><code>lua_pushliteral</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3825 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3826 <pre>const char *lua_pushliteral (lua_State *L, const char *s);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3827 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3828 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3829 This macro is equivalent to <a href="#lua_pushlstring"><code>lua_pushlstring</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3830 but can be used only when <code>s</code> is a literal string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3831 It automatically provides the string length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3833 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3834 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3835 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3836 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3837 <hr><h3><a name="lua_pushlstring"><code>lua_pushlstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3838 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3839 <pre>const char *lua_pushlstring (lua_State *L, const char *s, size_t len);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3840 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3841 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3842 Pushes the string pointed to by <code>s</code> with size <code>len</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3843 onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3844 Lua makes (or reuses) an internal copy of the given string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3845 so the memory at <code>s</code> can be freed or reused immediately after |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3846 the function returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3847 The string can contain any binary data, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3848 including embedded zeros. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3849 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3850 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3851 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3852 Returns a pointer to the internal copy of the string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3853 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3854 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3855 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3856 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3857 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3858 <hr><h3><a name="lua_pushnil"><code>lua_pushnil</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3859 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3860 <pre>void lua_pushnil (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3861 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3862 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3863 Pushes a nil value onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3864 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3867 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3868 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3869 <hr><h3><a name="lua_pushnumber"><code>lua_pushnumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3870 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3871 <pre>void lua_pushnumber (lua_State *L, lua_Number n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3872 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3873 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3874 Pushes a float with value <code>n</code> onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3875 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3876 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3877 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3878 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3879 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3880 <hr><h3><a name="lua_pushstring"><code>lua_pushstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3881 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3882 <pre>const char *lua_pushstring (lua_State *L, const char *s);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3883 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3884 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3885 Pushes the zero-terminated string pointed to by <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3886 onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3887 Lua makes (or reuses) an internal copy of the given string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3888 so the memory at <code>s</code> can be freed or reused immediately after |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3889 the function returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3890 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3891 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3892 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3893 Returns a pointer to the internal copy of the string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3894 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3895 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3896 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3897 If <code>s</code> is <code>NULL</code>, pushes <b>nil</b> and returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3898 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3899 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3900 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3901 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3902 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3903 <hr><h3><a name="lua_pushthread"><code>lua_pushthread</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3904 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3905 <pre>int lua_pushthread (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3906 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3907 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3908 Pushes the thread represented by <code>L</code> onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3909 Returns 1 if this thread is the main thread of its state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3911 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3912 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3913 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3914 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3915 <hr><h3><a name="lua_pushvalue"><code>lua_pushvalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3916 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3917 <pre>void lua_pushvalue (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3918 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3919 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3920 Pushes a copy of the element at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3921 onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3923 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3925 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3926 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3927 <hr><h3><a name="lua_pushvfstring"><code>lua_pushvfstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3928 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3929 <pre>const char *lua_pushvfstring (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3930 const char *fmt, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3931 va_list argp);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3933 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3934 Equivalent to <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>, except that it receives a <code>va_list</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3935 instead of a variable number of arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3937 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3938 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3939 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3941 <hr><h3><a name="lua_rawequal"><code>lua_rawequal</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3942 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3943 <pre>int lua_rawequal (lua_State *L, int index1, int index2);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3944 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3945 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3946 Returns 1 if the two values in indices <code>index1</code> and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3947 <code>index2</code> are primitively equal |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3948 (that is, without calling metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3949 Otherwise returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3950 Also returns 0 if any of the indices are not valid. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3951 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3952 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3953 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3954 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3955 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3956 <hr><h3><a name="lua_rawget"><code>lua_rawget</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3957 <span class="apii">[-1, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3958 <pre>int lua_rawget (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3959 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3960 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3961 Similar to <a href="#lua_gettable"><code>lua_gettable</code></a>, but does a raw access |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3962 (i.e., without metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3964 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3965 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3966 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3967 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3968 <hr><h3><a name="lua_rawgeti"><code>lua_rawgeti</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3969 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3970 <pre>int lua_rawgeti (lua_State *L, int index, lua_Integer n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3971 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3972 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3973 Pushes onto the stack the value <code>t[n]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3974 where <code>t</code> is the table at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3975 The access is raw; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3976 that is, it does not invoke metamethods. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3977 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3978 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3979 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3980 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3981 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3982 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3983 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3984 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3986 <hr><h3><a name="lua_rawgetp"><code>lua_rawgetp</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3987 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3988 <pre>int lua_rawgetp (lua_State *L, int index, const void *p);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3989 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3990 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3991 Pushes onto the stack the value <code>t[k]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3992 where <code>t</code> is the table at the given index and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3993 <code>k</code> is the pointer <code>p</code> represented as a light userdata. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3994 The access is raw; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3995 that is, it does not invoke metamethods. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3996 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3997 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3998 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
3999 Returns the type of the pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4000 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4001 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4002 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4003 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4005 <hr><h3><a name="lua_rawlen"><code>lua_rawlen</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4006 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4007 <pre>size_t lua_rawlen (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4008 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4009 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4010 Returns the raw "length" of the value at the given index: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4011 for strings, this is the string length; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4012 for tables, this is the result of the length operator ('<code>#</code>') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4013 with no metamethods; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4014 for userdata, this is the size of the block of memory allocated |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4015 for the userdata; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4016 for other values, it is 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4017 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4019 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4020 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4021 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4022 <hr><h3><a name="lua_rawset"><code>lua_rawset</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4023 <span class="apii">[-2, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4024 <pre>void lua_rawset (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4025 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4026 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4027 Similar to <a href="#lua_settable"><code>lua_settable</code></a>, but does a raw assignment |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4028 (i.e., without metamethods). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4029 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4030 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4031 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4034 <hr><h3><a name="lua_rawseti"><code>lua_rawseti</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4035 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4036 <pre>void lua_rawseti (lua_State *L, int index, lua_Integer i);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4037 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4038 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4039 Does the equivalent of <code>t[i] = v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4040 where <code>t</code> is the table at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4041 and <code>v</code> is the value at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4042 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4043 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4044 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4045 This function pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4046 The assignment is raw; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4047 that is, it does not invoke metamethods. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4048 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4049 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4051 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4052 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4053 <hr><h3><a name="lua_rawsetp"><code>lua_rawsetp</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4054 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4055 <pre>void lua_rawsetp (lua_State *L, int index, const void *p);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4057 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4058 Does the equivalent of <code>t[k] = v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4059 where <code>t</code> is the table at the given index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4060 <code>k</code> is the pointer <code>p</code> represented as a light userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4061 and <code>v</code> is the value at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4062 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4063 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4064 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4065 This function pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4066 The assignment is raw; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4067 that is, it does not invoke metamethods. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4068 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4069 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4070 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4072 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4073 <hr><h3><a name="lua_Reader"><code>lua_Reader</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4074 <pre>typedef const char * (*lua_Reader) (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4075 void *data, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4076 size_t *size);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4077 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4078 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4079 The reader function used by <a href="#lua_load"><code>lua_load</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4080 Every time it needs another piece of the chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4081 <a href="#lua_load"><code>lua_load</code></a> calls the reader, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4082 passing along its <code>data</code> parameter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4083 The reader must return a pointer to a block of memory |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4084 with a new piece of the chunk |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4085 and set <code>size</code> to the block size. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4086 The block must exist until the reader function is called again. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4087 To signal the end of the chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4088 the reader must return <code>NULL</code> or set <code>size</code> to zero. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4089 The reader function may return pieces of any size greater than zero. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4090 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4091 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4092 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4093 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4094 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4095 <hr><h3><a name="lua_register"><code>lua_register</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4096 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4097 <pre>void lua_register (lua_State *L, const char *name, lua_CFunction f);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4099 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4100 Sets the C function <code>f</code> as the new value of global <code>name</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4101 It is defined as a macro: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4102 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4103 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4104 #define lua_register(L,n,f) \ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4105 (lua_pushcfunction(L, f), lua_setglobal(L, n)) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4106 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4109 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4110 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4111 <hr><h3><a name="lua_remove"><code>lua_remove</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4112 <span class="apii">[-1, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4113 <pre>void lua_remove (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4114 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4115 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4116 Removes the element at the given valid index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4117 shifting down the elements above this index to fill the gap. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4118 This function cannot be called with a pseudo-index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4119 because a pseudo-index is not an actual stack position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4120 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4121 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4122 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4123 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4124 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4125 <hr><h3><a name="lua_replace"><code>lua_replace</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4126 <span class="apii">[-1, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4127 <pre>void lua_replace (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4128 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4129 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4130 Moves the top element into the given valid index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4131 without shifting any element |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4132 (therefore replacing the value at the given index), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4133 and then pops the top element. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4134 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4135 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4136 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4137 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4138 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4139 <hr><h3><a name="lua_resume"><code>lua_resume</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4140 <span class="apii">[-?, +?, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4141 <pre>int lua_resume (lua_State *L, lua_State *from, int nargs);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4143 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4144 Starts and resumes a coroutine in a given thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4145 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4146 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4147 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4148 To start a coroutine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4149 you push onto the thread stack the main function plus any arguments; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4150 then you call <a href="#lua_resume"><code>lua_resume</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4151 with <code>nargs</code> being the number of arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4152 This call returns when the coroutine suspends or finishes its execution. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4153 When it returns, the stack contains all values passed to <a href="#lua_yield"><code>lua_yield</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4154 or all values returned by the body function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4155 <a href="#lua_resume"><code>lua_resume</code></a> returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4156 <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the coroutine yields, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4157 <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> if the coroutine finishes its execution |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4158 without errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4159 or an error code in case of errors (see <a href="#lua_pcall"><code>lua_pcall</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4160 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4161 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4162 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4163 In case of errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4164 the stack is not unwound, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4165 so you can use the debug API over it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4166 The error message is on the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4169 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4170 To resume a coroutine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4171 you remove any results from the last <a href="#lua_yield"><code>lua_yield</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4172 put on its stack only the values to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4173 be passed as results from <code>yield</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4174 and then call <a href="#lua_resume"><code>lua_resume</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4175 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4176 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4177 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4178 The parameter <code>from</code> represents the coroutine that is resuming <code>L</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4179 If there is no such coroutine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4180 this parameter can be <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4182 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4183 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4185 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4186 <hr><h3><a name="lua_rotate"><code>lua_rotate</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4187 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4188 <pre>void lua_rotate (lua_State *L, int idx, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4190 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4191 Rotates the stack elements from <code>idx</code> to the top <code>n</code> positions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4192 in the direction of the top, for a positive <code>n</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4193 or <code>-n</code> positions in the direction of the bottom, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4194 for a negative <code>n</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4195 The absolute value of <code>n</code> must not be greater than the size |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4196 of the slice being rotated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4198 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4199 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4200 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4202 <hr><h3><a name="lua_setallocf"><code>lua_setallocf</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4203 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4204 <pre>void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4206 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4207 Changes the allocator function of a given state to <code>f</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4208 with user data <code>ud</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4210 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4211 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4212 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4214 <hr><h3><a name="lua_setfield"><code>lua_setfield</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4215 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4216 <pre>void lua_setfield (lua_State *L, int index, const char *k);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4218 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4219 Does the equivalent to <code>t[k] = v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4220 where <code>t</code> is the value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4221 and <code>v</code> is the value at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4222 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4223 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4224 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4225 This function pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4226 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4227 for the "newindex" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4228 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4229 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4230 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4231 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4232 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4233 <hr><h3><a name="lua_setglobal"><code>lua_setglobal</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4234 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4235 <pre>void lua_setglobal (lua_State *L, const char *name);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4237 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4238 Pops a value from the stack and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4239 sets it as the new value of global <code>name</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4240 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4243 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4244 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4245 <hr><h3><a name="lua_seti"><code>lua_seti</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4246 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4247 <pre>void lua_seti (lua_State *L, int index, lua_Integer n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4248 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4249 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4250 Does the equivalent to <code>t[n] = v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4251 where <code>t</code> is the value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4252 and <code>v</code> is the value at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4255 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4256 This function pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4257 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4258 for the "newindex" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4259 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4260 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4261 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4262 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4263 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4264 <hr><h3><a name="lua_setmetatable"><code>lua_setmetatable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4265 <span class="apii">[-1, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4266 <pre>void lua_setmetatable (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4267 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4268 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4269 Pops a table from the stack and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4270 sets it as the new metatable for the value at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4271 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4272 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4273 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4275 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4276 <hr><h3><a name="lua_settable"><code>lua_settable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4277 <span class="apii">[-2, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4278 <pre>void lua_settable (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4280 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4281 Does the equivalent to <code>t[k] = v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4282 where <code>t</code> is the value at the given index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4283 <code>v</code> is the value at the top of the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4284 and <code>k</code> is the value just below the top. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4285 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4286 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4287 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4288 This function pops both the key and the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4289 As in Lua, this function may trigger a metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4290 for the "newindex" event (see <a href="#2.4">§2.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4291 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4292 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4293 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4294 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4295 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4296 <hr><h3><a name="lua_settop"><code>lua_settop</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4297 <span class="apii">[-?, +?, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4298 <pre>void lua_settop (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4300 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4301 Accepts any index, or 0, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4302 and sets the stack top to this index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4303 If the new top is larger than the old one, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4304 then the new elements are filled with <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4305 If <code>index</code> is 0, then all stack elements are removed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4306 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4307 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4308 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4309 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4310 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4311 <hr><h3><a name="lua_setuservalue"><code>lua_setuservalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4312 <span class="apii">[-1, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4313 <pre>void lua_setuservalue (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4314 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4315 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4316 Pops a value from the stack and sets it as |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4317 the new value associated to the userdata at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4318 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4319 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4320 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4321 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4322 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4323 <hr><h3><a name="lua_State"><code>lua_State</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4324 <pre>typedef struct lua_State lua_State;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4325 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4326 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4327 An opaque structure that points to a thread and indirectly |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4328 (through the thread) to the whole state of a Lua interpreter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4329 The Lua library is fully reentrant: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4330 it has no global variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4331 All information about a state is accessible through this structure. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4332 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4333 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4334 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4335 A pointer to this structure must be passed as the first argument to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4336 every function in the library, except to <a href="#lua_newstate"><code>lua_newstate</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4337 which creates a Lua state from scratch. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4338 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4339 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4340 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4341 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4342 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4343 <hr><h3><a name="lua_status"><code>lua_status</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4344 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4345 <pre>int lua_status (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4346 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4347 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4348 Returns the status of the thread <code>L</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4351 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4352 The status can be 0 (<a href="#pdf-LUA_OK"><code>LUA_OK</code></a>) for a normal thread, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4353 an error code if the thread finished the execution |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4354 of a <a href="#lua_resume"><code>lua_resume</code></a> with an error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4355 or <a name="pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the thread is suspended. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4357 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4358 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4359 You can only call functions in threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4360 You can resume threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4361 (to start a new coroutine) or <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4362 (to resume a coroutine). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4363 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4365 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4366 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4367 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4368 <hr><h3><a name="lua_stringtonumber"><code>lua_stringtonumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4369 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4370 <pre>size_t lua_stringtonumber (lua_State *L, const char *s);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4371 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4372 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4373 Converts the zero-terminated string <code>s</code> to a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4374 pushes that number into the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4375 and returns the total size of the string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4376 that is, its length plus one. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4377 The conversion can result in an integer or a float, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4378 according to the lexical conventions of Lua (see <a href="#3.1">§3.1</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4379 The string may have leading and trailing spaces and a sign. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4380 If the string is not a valid numeral, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4381 returns 0 and pushes nothing. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4382 (Note that the result can be used as a boolean, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4383 true if the conversion succeeds.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4384 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4385 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4387 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4388 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4389 <hr><h3><a name="lua_toboolean"><code>lua_toboolean</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4390 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4391 <pre>int lua_toboolean (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4392 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4393 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4394 Converts the Lua value at the given index to a C boolean |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4395 value (0 or 1). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4396 Like all tests in Lua, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4397 <a href="#lua_toboolean"><code>lua_toboolean</code></a> returns true for any Lua value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4398 different from <b>false</b> and <b>nil</b>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4399 otherwise it returns false. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4400 (If you want to accept only actual boolean values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4401 use <a href="#lua_isboolean"><code>lua_isboolean</code></a> to test the value's type.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4403 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4404 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4405 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4406 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4407 <hr><h3><a name="lua_tocfunction"><code>lua_tocfunction</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4408 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4409 <pre>lua_CFunction lua_tocfunction (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4410 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4411 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4412 Converts a value at the given index to a C function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4413 That value must be a C function; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4414 otherwise, returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4415 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4416 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4418 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4419 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4420 <hr><h3><a name="lua_tointeger"><code>lua_tointeger</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4421 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4422 <pre>lua_Integer lua_tointeger (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4423 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4424 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4425 Equivalent to <a href="#lua_tointegerx"><code>lua_tointegerx</code></a> with <code>isnum</code> equal to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4426 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4427 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4428 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4429 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4430 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4431 <hr><h3><a name="lua_tointegerx"><code>lua_tointegerx</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4432 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4433 <pre>lua_Integer lua_tointegerx (lua_State *L, int index, int *isnum);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4434 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4435 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4436 Converts the Lua value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4437 to the signed integral type <a href="#lua_Integer"><code>lua_Integer</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4438 The Lua value must be an integer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4439 or a number or string convertible to an integer (see <a href="#3.4.3">§3.4.3</a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4440 otherwise, <code>lua_tointegerx</code> returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4441 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4443 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4444 If <code>isnum</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4445 its referent is assigned a boolean value that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4446 indicates whether the operation succeeded. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4448 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4449 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4450 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4451 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4452 <hr><h3><a name="lua_tolstring"><code>lua_tolstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4453 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4454 <pre>const char *lua_tolstring (lua_State *L, int index, size_t *len);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4455 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4456 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4457 Converts the Lua value at the given index to a C string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4458 If <code>len</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4459 it also sets <code>*len</code> with the string length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4460 The Lua value must be a string or a number; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4461 otherwise, the function returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4462 If the value is a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4463 then <code>lua_tolstring</code> also |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4464 <em>changes the actual value in the stack to a string</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4465 (This change confuses <a href="#lua_next"><code>lua_next</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4466 when <code>lua_tolstring</code> is applied to keys during a table traversal.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4467 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4468 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4469 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4470 <code>lua_tolstring</code> returns a fully aligned pointer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4471 to a string inside the Lua state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4472 This string always has a zero ('<code>\0</code>') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4473 after its last character (as in C), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4474 but can contain other zeros in its body. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4475 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4476 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4477 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4478 Because Lua has garbage collection, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4479 there is no guarantee that the pointer returned by <code>lua_tolstring</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4480 will be valid after the corresponding Lua value is removed from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4481 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4482 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4484 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4485 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4486 <hr><h3><a name="lua_tonumber"><code>lua_tonumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4487 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4488 <pre>lua_Number lua_tonumber (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4489 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4490 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4491 Equivalent to <a href="#lua_tonumberx"><code>lua_tonumberx</code></a> with <code>isnum</code> equal to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4492 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4493 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4494 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4495 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4496 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4497 <hr><h3><a name="lua_tonumberx"><code>lua_tonumberx</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4498 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4499 <pre>lua_Number lua_tonumberx (lua_State *L, int index, int *isnum);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4500 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4501 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4502 Converts the Lua value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4503 to the C type <a href="#lua_Number"><code>lua_Number</code></a> (see <a href="#lua_Number"><code>lua_Number</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4504 The Lua value must be a number or a string convertible to a number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4505 (see <a href="#3.4.3">§3.4.3</a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4506 otherwise, <a href="#lua_tonumberx"><code>lua_tonumberx</code></a> returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4507 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4508 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4509 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4510 If <code>isnum</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4511 its referent is assigned a boolean value that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4512 indicates whether the operation succeeded. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4513 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4514 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4515 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4516 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4517 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4518 <hr><h3><a name="lua_topointer"><code>lua_topointer</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4519 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4520 <pre>const void *lua_topointer (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4521 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4522 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4523 Converts the value at the given index to a generic |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4524 C pointer (<code>void*</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4525 The value can be a userdata, a table, a thread, or a function; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4526 otherwise, <code>lua_topointer</code> returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4527 Different objects will give different pointers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4528 There is no way to convert the pointer back to its original value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4529 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4530 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4531 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4532 Typically this function is used only for debug information. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4533 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4534 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4535 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4536 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4537 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4538 <hr><h3><a name="lua_tostring"><code>lua_tostring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4539 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4540 <pre>const char *lua_tostring (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4541 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4542 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4543 Equivalent to <a href="#lua_tolstring"><code>lua_tolstring</code></a> with <code>len</code> equal to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4544 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4545 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4546 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4547 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4548 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4549 <hr><h3><a name="lua_tothread"><code>lua_tothread</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4550 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4551 <pre>lua_State *lua_tothread (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4552 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4553 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4554 Converts the value at the given index to a Lua thread |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4555 (represented as <code>lua_State*</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4556 This value must be a thread; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4557 otherwise, the function returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4558 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4559 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4561 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4562 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4563 <hr><h3><a name="lua_touserdata"><code>lua_touserdata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4564 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4565 <pre>void *lua_touserdata (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4566 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4567 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4568 If the value at the given index is a full userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4569 returns its block address. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4570 If the value is a light userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4571 returns its pointer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4572 Otherwise, returns <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4573 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4574 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4575 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4576 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4577 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4578 <hr><h3><a name="lua_type"><code>lua_type</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4579 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4580 <pre>int lua_type (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4581 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4582 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4583 Returns the type of the value in the given valid index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4584 or <code>LUA_TNONE</code> for a non-valid (but acceptable) index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4585 The types returned by <a href="#lua_type"><code>lua_type</code></a> are coded by the following constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4586 defined in <code>lua.h</code>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4587 <a name="pdf-LUA_TNIL"><code>LUA_TNIL</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4588 <a name="pdf-LUA_TNUMBER"><code>LUA_TNUMBER</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4589 <a name="pdf-LUA_TBOOLEAN"><code>LUA_TBOOLEAN</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4590 <a name="pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4591 <a name="pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4592 <a name="pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4593 <a name="pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4594 <a name="pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4595 and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4596 <a name="pdf-LUA_TLIGHTUSERDATA"><code>LUA_TLIGHTUSERDATA</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4597 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4598 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4599 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4600 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4601 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4602 <hr><h3><a name="lua_typename"><code>lua_typename</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4603 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4604 <pre>const char *lua_typename (lua_State *L, int tp);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4605 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4606 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4607 Returns the name of the type encoded by the value <code>tp</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4608 which must be one the values returned by <a href="#lua_type"><code>lua_type</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4609 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4610 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4611 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4612 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4614 <hr><h3><a name="lua_Unsigned"><code>lua_Unsigned</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4615 <pre>typedef ... lua_Unsigned;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4616 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4617 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4618 The unsigned version of <a href="#lua_Integer"><code>lua_Integer</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4619 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4620 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4621 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4622 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4623 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4624 <hr><h3><a name="lua_upvalueindex"><code>lua_upvalueindex</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4625 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4626 <pre>int lua_upvalueindex (int i);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4627 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4628 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4629 Returns the pseudo-index that represents the <code>i</code>-th upvalue of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4630 the running function (see <a href="#4.4">§4.4</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4631 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4632 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4633 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4634 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4635 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4636 <hr><h3><a name="lua_version"><code>lua_version</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4637 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4638 <pre>const lua_Number *lua_version (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4639 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4640 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4641 Returns the address of the version number stored in the Lua core. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4642 When called with a valid <a href="#lua_State"><code>lua_State</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4643 returns the address of the version used to create that state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4644 When called with <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4645 returns the address of the version running the call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4648 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4649 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4650 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4651 <hr><h3><a name="lua_Writer"><code>lua_Writer</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4652 <pre>typedef int (*lua_Writer) (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4653 const void* p, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4654 size_t sz, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4655 void* ud);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4656 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4657 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4658 The type of the writer function used by <a href="#lua_dump"><code>lua_dump</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4659 Every time it produces another piece of chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4660 <a href="#lua_dump"><code>lua_dump</code></a> calls the writer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4661 passing along the buffer to be written (<code>p</code>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4662 its size (<code>sz</code>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4663 and the <code>data</code> parameter supplied to <a href="#lua_dump"><code>lua_dump</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4664 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4665 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4666 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4667 The writer returns an error code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4668 0 means no errors; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4669 any other value means an error and stops <a href="#lua_dump"><code>lua_dump</code></a> from |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4670 calling the writer again. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4671 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4672 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4673 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4674 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4675 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4676 <hr><h3><a name="lua_xmove"><code>lua_xmove</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4677 <span class="apii">[-?, +?, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4678 <pre>void lua_xmove (lua_State *from, lua_State *to, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4679 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4680 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4681 Exchange values between different threads of the same state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4682 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4683 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4684 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4685 This function pops <code>n</code> values from the stack <code>from</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4686 and pushes them onto the stack <code>to</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4687 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4688 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4689 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4690 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4691 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4692 <hr><h3><a name="lua_yield"><code>lua_yield</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4693 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4694 <pre>int lua_yield (lua_State *L, int nresults);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4696 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4697 This function is equivalent to <a href="#lua_yieldk"><code>lua_yieldk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4698 but it has no continuation (see <a href="#4.7">§4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4699 Therefore, when the thread resumes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4700 it continues the function that called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4701 the function calling <code>lua_yield</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4702 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4703 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4704 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4705 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4706 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4707 <hr><h3><a name="lua_yieldk"><code>lua_yieldk</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4708 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4709 <pre>int lua_yieldk (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4710 int nresults, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4711 lua_KContext ctx, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4712 lua_KFunction k);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4713 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4714 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4715 Yields a coroutine (thread). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4716 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4717 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4718 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4719 When a C function calls <a href="#lua_yieldk"><code>lua_yieldk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4720 the running coroutine suspends its execution, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4721 and the call to <a href="#lua_resume"><code>lua_resume</code></a> that started this coroutine returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4722 The parameter <code>nresults</code> is the number of values from the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4723 that will be passed as results to <a href="#lua_resume"><code>lua_resume</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4726 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4727 When the coroutine is resumed again, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4728 Lua calls the given continuation function <code>k</code> to continue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4729 the execution of the C function that yielded (see <a href="#4.7">§4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4730 This continuation function receives the same stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4731 from the previous function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4732 with the <code>n</code> results removed and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4733 replaced by the arguments passed to <a href="#lua_resume"><code>lua_resume</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4734 Moreover, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4735 the continuation function receives the value <code>ctx</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4736 that was passed to <a href="#lua_yieldk"><code>lua_yieldk</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4738 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4739 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4740 Usually, this function does not return; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4741 when the coroutine eventually resumes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4742 it continues executing the continuation function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4743 However, there is one special case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4744 which is when this function is called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4745 from inside a line hook (see <a href="#4.9">§4.9</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4746 In that case, <code>lua_yieldk</code> should be called with no continuation |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4747 (probably in the form of <a href="#lua_yield"><code>lua_yield</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4748 and the hook should return immediately after the call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4749 Lua will yield and, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4750 when the coroutine resumes again, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4751 it will continue the normal execution |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4752 of the (Lua) function that triggered the hook. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4754 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4755 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4756 This function can raise an error if it is called from a thread |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4757 with a pending C call with no continuation function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4758 or it is called from a thread that is not running inside a resume |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4759 (e.g., the main thread). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4760 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4761 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4762 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4763 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4764 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4765 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4766 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4767 <h2>4.9 – <a name="4.9">The Debug Interface</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4768 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4769 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4770 Lua has no built-in debugging facilities. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4771 Instead, it offers a special interface |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4772 by means of functions and <em>hooks</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4773 This interface allows the construction of different |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4774 kinds of debuggers, profilers, and other tools |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4775 that need "inside information" from the interpreter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4776 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4777 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4778 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4779 <hr><h3><a name="lua_Debug"><code>lua_Debug</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4780 <pre>typedef struct lua_Debug { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4781 int event; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4782 const char *name; /* (n) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4783 const char *namewhat; /* (n) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4784 const char *what; /* (S) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4785 const char *source; /* (S) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4786 int currentline; /* (l) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4787 int linedefined; /* (S) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4788 int lastlinedefined; /* (S) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4789 unsigned char nups; /* (u) number of upvalues */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4790 unsigned char nparams; /* (u) number of parameters */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4791 char isvararg; /* (u) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4792 char istailcall; /* (t) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4793 char short_src[LUA_IDSIZE]; /* (S) */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4794 /* private part */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4795 <em>other fields</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4796 } lua_Debug;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4797 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4798 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4799 A structure used to carry different pieces of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4800 information about a function or an activation record. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4801 <a href="#lua_getstack"><code>lua_getstack</code></a> fills only the private part |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4802 of this structure, for later use. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4803 To fill the other fields of <a href="#lua_Debug"><code>lua_Debug</code></a> with useful information, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4804 call <a href="#lua_getinfo"><code>lua_getinfo</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4805 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4807 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4808 The fields of <a href="#lua_Debug"><code>lua_Debug</code></a> have the following meaning: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4810 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4811 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4812 <li><b><code>source</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4813 the name of the chunk that created the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4814 If <code>source</code> starts with a '<code>@</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4815 it means that the function was defined in a file where |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4816 the file name follows the '<code>@</code>'. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4817 If <code>source</code> starts with a '<code>=</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4818 the remainder of its contents describe the source in a user-dependent manner. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4819 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4820 the function was defined in a string where |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4821 <code>source</code> is that string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4822 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4823 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4824 <li><b><code>short_src</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4825 a "printable" version of <code>source</code>, to be used in error messages. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4826 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4827 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4828 <li><b><code>linedefined</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4829 the line number where the definition of the function starts. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4830 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4831 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4832 <li><b><code>lastlinedefined</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4833 the line number where the definition of the function ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4834 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4835 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4836 <li><b><code>what</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4837 the string <code>"Lua"</code> if the function is a Lua function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4838 <code>"C"</code> if it is a C function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4839 <code>"main"</code> if it is the main part of a chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4840 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4841 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4842 <li><b><code>currentline</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4843 the current line where the given function is executing. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4844 When no line information is available, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4845 <code>currentline</code> is set to -1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4846 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4847 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4848 <li><b><code>name</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4849 a reasonable name for the given function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4850 Because functions in Lua are first-class values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4851 they do not have a fixed name: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4852 some functions can be the value of multiple global variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4853 while others can be stored only in a table field. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4854 The <code>lua_getinfo</code> function checks how the function was |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4855 called to find a suitable name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4856 If it cannot find a name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4857 then <code>name</code> is set to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4858 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4859 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4860 <li><b><code>namewhat</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4861 explains the <code>name</code> field. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4862 The value of <code>namewhat</code> can be |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4863 <code>"global"</code>, <code>"local"</code>, <code>"method"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4864 <code>"field"</code>, <code>"upvalue"</code>, or <code>""</code> (the empty string), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4865 according to how the function was called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4866 (Lua uses the empty string when no other option seems to apply.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4867 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4868 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4869 <li><b><code>istailcall</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4870 true if this function invocation was called by a tail call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4871 In this case, the caller of this level is not in the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4872 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4873 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4874 <li><b><code>nups</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4875 the number of upvalues of the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4876 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4877 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4878 <li><b><code>nparams</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4879 the number of fixed parameters of the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4880 (always 0 for C functions). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4881 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4882 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4883 <li><b><code>isvararg</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4884 true if the function is a vararg function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4885 (always true for C functions). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4886 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4887 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4888 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4889 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4890 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4891 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4892 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4893 <hr><h3><a name="lua_gethook"><code>lua_gethook</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4894 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4895 <pre>lua_Hook lua_gethook (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4896 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4897 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4898 Returns the current hook function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4899 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4900 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4901 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4902 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4903 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4904 <hr><h3><a name="lua_gethookcount"><code>lua_gethookcount</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4905 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4906 <pre>int lua_gethookcount (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4907 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4908 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4909 Returns the current hook count. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4911 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4912 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4913 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4914 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4915 <hr><h3><a name="lua_gethookmask"><code>lua_gethookmask</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4916 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4917 <pre>int lua_gethookmask (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4918 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4919 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4920 Returns the current hook mask. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4921 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4923 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4925 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4926 <hr><h3><a name="lua_getinfo"><code>lua_getinfo</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4927 <span class="apii">[-(0|1), +(0|1|2), <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4928 <pre>int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4929 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4930 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4931 Gets information about a specific function or function invocation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4933 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4934 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4935 To get information about a function invocation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4936 the parameter <code>ar</code> must be a valid activation record that was |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4937 filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4938 given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4939 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4941 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4942 To get information about a function you push it onto the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4943 and start the <code>what</code> string with the character '<code>></code>'. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4944 (In that case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4945 <code>lua_getinfo</code> pops the function from the top of the stack.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4946 For instance, to know in which line a function <code>f</code> was defined, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4947 you can write the following code: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4948 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4949 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4950 lua_Debug ar; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4951 lua_getglobal(L, "f"); /* get global 'f' */ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4952 lua_getinfo(L, ">S", &ar); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4953 printf("%d\n", ar.linedefined); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4954 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4955 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4956 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4957 Each character in the string <code>what</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4958 selects some fields of the structure <code>ar</code> to be filled or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4959 a value to be pushed on the stack: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4960 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4961 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4962 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4963 <li><b>'<code>n</code>': </b> fills in the field <code>name</code> and <code>namewhat</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4964 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4965 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4966 <li><b>'<code>S</code>': </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4967 fills in the fields <code>source</code>, <code>short_src</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4968 <code>linedefined</code>, <code>lastlinedefined</code>, and <code>what</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4969 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4970 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4971 <li><b>'<code>l</code>': </b> fills in the field <code>currentline</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4972 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4973 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4974 <li><b>'<code>t</code>': </b> fills in the field <code>istailcall</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4975 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4976 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4977 <li><b>'<code>u</code>': </b> fills in the fields |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4978 <code>nups</code>, <code>nparams</code>, and <code>isvararg</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4979 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4980 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4981 <li><b>'<code>f</code>': </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4982 pushes onto the stack the function that is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4983 running at the given level; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4984 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4986 <li><b>'<code>L</code>': </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4987 pushes onto the stack a table whose indices are the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4988 numbers of the lines that are valid on the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4989 (A <em>valid line</em> is a line with some associated code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4990 that is, a line where you can put a break point. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4991 Non-valid lines include empty lines and comments.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4992 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4994 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4995 If this option is given together with option '<code>f</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4996 its table is pushed after the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4997 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4998 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
4999 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5000 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5001 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5002 This function returns 0 on error |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5003 (for instance, an invalid option in <code>what</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5006 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5007 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5008 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5009 <hr><h3><a name="lua_getlocal"><code>lua_getlocal</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5010 <span class="apii">[-0, +(0|1), –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5011 <pre>const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5012 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5013 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5014 Gets information about a local variable of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5015 a given activation record or a given function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5016 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5017 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5018 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5019 In the first case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5020 the parameter <code>ar</code> must be a valid activation record that was |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5021 filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5022 given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5023 The index <code>n</code> selects which local variable to inspect; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5024 see <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for details about variable indices |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5025 and names. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5026 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5027 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5028 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5029 <a href="#lua_getlocal"><code>lua_getlocal</code></a> pushes the variable's value onto the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5030 and returns its name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5031 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5033 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5034 In the second case, <code>ar</code> must be <code>NULL</code> and the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5035 to be inspected must be at the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5036 In this case, only parameters of Lua functions are visible |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5037 (as there is no information about what variables are active) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5038 and no values are pushed onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5039 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5040 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5041 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5042 Returns <code>NULL</code> (and pushes nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5043 when the index is greater than |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5044 the number of active local variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5045 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5046 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5047 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5048 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5049 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5050 <hr><h3><a name="lua_getstack"><code>lua_getstack</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5051 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5052 <pre>int lua_getstack (lua_State *L, int level, lua_Debug *ar);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5053 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5054 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5055 Gets information about the interpreter runtime stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5057 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5058 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5059 This function fills parts of a <a href="#lua_Debug"><code>lua_Debug</code></a> structure with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5060 an identification of the <em>activation record</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5061 of the function executing at a given level. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5062 Level 0 is the current running function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5063 whereas level <em>n+1</em> is the function that has called level <em>n</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5064 (except for tail calls, which do not count on the stack). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5065 When there are no errors, <a href="#lua_getstack"><code>lua_getstack</code></a> returns 1; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5066 when called with a level greater than the stack depth, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5067 it returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5068 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5069 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5070 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5072 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5073 <hr><h3><a name="lua_getupvalue"><code>lua_getupvalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5074 <span class="apii">[-0, +(0|1), –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5075 <pre>const char *lua_getupvalue (lua_State *L, int funcindex, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5076 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5077 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5078 Gets information about a closure's upvalue. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5079 (For Lua functions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5080 upvalues are the external local variables that the function uses, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5081 and that are consequently included in its closure.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5082 <a href="#lua_getupvalue"><code>lua_getupvalue</code></a> gets the index <code>n</code> of an upvalue, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5083 pushes the upvalue's value onto the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5084 and returns its name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5085 <code>funcindex</code> points to the closure in the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5086 (Upvalues have no particular order, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5087 as they are active through the whole function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5088 So, they are numbered in an arbitrary order.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5089 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5090 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5091 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5092 Returns <code>NULL</code> (and pushes nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5093 when the index is greater than the number of upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5094 For C functions, this function uses the empty string <code>""</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5095 as a name for all upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5096 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5097 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5099 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5100 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5101 <hr><h3><a name="lua_Hook"><code>lua_Hook</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5102 <pre>typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5103 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5104 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5105 Type for debugging hook functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5106 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5108 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5109 Whenever a hook is called, its <code>ar</code> argument has its field |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5110 <code>event</code> set to the specific event that triggered the hook. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5111 Lua identifies these events with the following constants: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5112 <a name="pdf-LUA_HOOKCALL"><code>LUA_HOOKCALL</code></a>, <a name="pdf-LUA_HOOKRET"><code>LUA_HOOKRET</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5113 <a name="pdf-LUA_HOOKTAILCALL"><code>LUA_HOOKTAILCALL</code></a>, <a name="pdf-LUA_HOOKLINE"><code>LUA_HOOKLINE</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5114 and <a name="pdf-LUA_HOOKCOUNT"><code>LUA_HOOKCOUNT</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5115 Moreover, for line events, the field <code>currentline</code> is also set. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5116 To get the value of any other field in <code>ar</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5117 the hook must call <a href="#lua_getinfo"><code>lua_getinfo</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5118 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5119 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5120 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5121 For call events, <code>event</code> can be <code>LUA_HOOKCALL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5122 the normal value, or <code>LUA_HOOKTAILCALL</code>, for a tail call; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5123 in this case, there will be no corresponding return event. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5124 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5125 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5126 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5127 While Lua is running a hook, it disables other calls to hooks. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5128 Therefore, if a hook calls back Lua to execute a function or a chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5129 this execution occurs without any calls to hooks. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5130 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5131 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5132 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5133 Hook functions cannot have continuations, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5134 that is, they cannot call <a href="#lua_yieldk"><code>lua_yieldk</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5135 <a href="#lua_pcallk"><code>lua_pcallk</code></a>, or <a href="#lua_callk"><code>lua_callk</code></a> with a non-null <code>k</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5136 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5137 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5138 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5139 Hook functions can yield under the following conditions: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5140 Only count and line events can yield |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5141 and they cannot yield any value; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5142 to yield a hook function must finish its execution |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5143 calling <a href="#lua_yield"><code>lua_yield</code></a> with <code>nresults</code> equal to zero. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5144 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5145 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5146 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5147 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5148 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5149 <hr><h3><a name="lua_sethook"><code>lua_sethook</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5150 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5151 <pre>void lua_sethook (lua_State *L, lua_Hook f, int mask, int count);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5152 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5153 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5154 Sets the debugging hook function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5156 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5157 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5158 Argument <code>f</code> is the hook function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5159 <code>mask</code> specifies on which events the hook will be called: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5160 it is formed by a bitwise or of the constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5161 <a name="pdf-LUA_MASKCALL"><code>LUA_MASKCALL</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5162 <a name="pdf-LUA_MASKRET"><code>LUA_MASKRET</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5163 <a name="pdf-LUA_MASKLINE"><code>LUA_MASKLINE</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5164 and <a name="pdf-LUA_MASKCOUNT"><code>LUA_MASKCOUNT</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5165 The <code>count</code> argument is only meaningful when the mask |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5166 includes <code>LUA_MASKCOUNT</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5167 For each event, the hook is called as explained below: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5169 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5170 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5171 <li><b>The call hook: </b> is called when the interpreter calls a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5172 The hook is called just after Lua enters the new function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5173 before the function gets its arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5174 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5175 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5176 <li><b>The return hook: </b> is called when the interpreter returns from a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5177 The hook is called just before Lua leaves the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5178 There is no standard way to access the values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5179 to be returned by the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5180 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5182 <li><b>The line hook: </b> is called when the interpreter is about to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5183 start the execution of a new line of code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5184 or when it jumps back in the code (even to the same line). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5185 (This event only happens while Lua is executing a Lua function.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5186 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5187 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5188 <li><b>The count hook: </b> is called after the interpreter executes every |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5189 <code>count</code> instructions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5190 (This event only happens while Lua is executing a Lua function.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5191 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5192 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5193 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5194 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5195 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5196 A hook is disabled by setting <code>mask</code> to zero. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5198 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5199 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5200 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5202 <hr><h3><a name="lua_setlocal"><code>lua_setlocal</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5203 <span class="apii">[-(0|1), +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5204 <pre>const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5206 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5207 Sets the value of a local variable of a given activation record. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5208 Parameters <code>ar</code> and <code>n</code> are as in <a href="#lua_getlocal"><code>lua_getlocal</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5209 (see <a href="#lua_getlocal"><code>lua_getlocal</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5210 <a href="#lua_setlocal"><code>lua_setlocal</code></a> assigns the value at the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5211 to the variable and returns its name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5212 It also pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5214 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5215 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5216 Returns <code>NULL</code> (and pops nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5217 when the index is greater than |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5218 the number of active local variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5219 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5220 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5221 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5222 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5223 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5224 <hr><h3><a name="lua_setupvalue"><code>lua_setupvalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5225 <span class="apii">[-(0|1), +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5226 <pre>const char *lua_setupvalue (lua_State *L, int funcindex, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5227 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5228 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5229 Sets the value of a closure's upvalue. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5230 It assigns the value at the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5231 to the upvalue and returns its name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5232 It also pops the value from the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5233 Parameters <code>funcindex</code> and <code>n</code> are as in the <a href="#lua_getupvalue"><code>lua_getupvalue</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5234 (see <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5237 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5238 Returns <code>NULL</code> (and pops nothing) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5239 when the index is greater than the number of upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5240 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5243 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5244 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5245 <hr><h3><a name="lua_upvalueid"><code>lua_upvalueid</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5246 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5247 <pre>void *lua_upvalueid (lua_State *L, int funcindex, int n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5248 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5249 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5250 Returns a unique identifier for the upvalue numbered <code>n</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5251 from the closure at index <code>funcindex</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5252 Parameters <code>funcindex</code> and <code>n</code> are as in the <a href="#lua_getupvalue"><code>lua_getupvalue</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5253 (see <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5254 (but <code>n</code> cannot be greater than the number of upvalues). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5255 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5256 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5257 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5258 These unique identifiers allow a program to check whether different |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5259 closures share upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5260 Lua closures that share an upvalue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5261 (that is, that access a same external local variable) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5262 will return identical ids for those upvalue indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5263 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5264 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5267 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5268 <hr><h3><a name="lua_upvaluejoin"><code>lua_upvaluejoin</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5269 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5270 <pre>void lua_upvaluejoin (lua_State *L, int funcindex1, int n1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5271 int funcindex2, int n2);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5272 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5273 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5274 Make the <code>n1</code>-th upvalue of the Lua closure at index <code>funcindex1</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5275 refer to the <code>n2</code>-th upvalue of the Lua closure at index <code>funcindex2</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5276 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5277 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5278 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5280 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5281 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5282 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5283 <h1>5 – <a name="5">The Auxiliary Library</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5284 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5285 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5286 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5287 The <em>auxiliary library</em> provides several convenient functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5288 to interface C with Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5289 While the basic API provides the primitive functions for all |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5290 interactions between C and Lua, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5291 the auxiliary library provides higher-level functions for some |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5292 common tasks. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5293 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5294 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5295 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5296 All functions and types from the auxiliary library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5297 are defined in header file <code>lauxlib.h</code> and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5298 have a prefix <code>luaL_</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5300 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5301 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5302 All functions in the auxiliary library are built on |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5303 top of the basic API, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5304 and so they provide nothing that cannot be done with that API. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5305 Nevertheless, the use of the auxiliary library ensures |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5306 more consistency to your code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5307 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5308 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5309 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5310 Several functions in the auxiliary library use internally some |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5311 extra stack slots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5312 When a function in the auxiliary library uses less than five slots, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5313 it does not check the stack size; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5314 it simply assumes that there are enough slots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5315 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5316 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5317 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5318 Several functions in the auxiliary library are used to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5319 check C function arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5320 Because the error message is formatted for arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5321 (e.g., "<code>bad argument #1</code>"), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5322 you should not use these functions for other stack values. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5323 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5324 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5325 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5326 Functions called <code>luaL_check*</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5327 always raise an error if the check is not satisfied. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5328 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5329 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5330 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5331 <h2>5.1 – <a name="5.1">Functions and Types</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5332 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5333 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5334 Here we list all functions and types from the auxiliary library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5335 in alphabetical order. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5336 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5337 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5338 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5339 <hr><h3><a name="luaL_addchar"><code>luaL_addchar</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5340 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5341 <pre>void luaL_addchar (luaL_Buffer *B, char c);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5342 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5343 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5344 Adds the byte <code>c</code> to the buffer <code>B</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5345 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5346 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5347 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5348 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5351 <hr><h3><a name="luaL_addlstring"><code>luaL_addlstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5352 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5353 <pre>void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5354 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5355 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5356 Adds the string pointed to by <code>s</code> with length <code>l</code> to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5357 the buffer <code>B</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5358 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5359 The string can contain embedded zeros. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5360 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5361 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5362 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5363 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5365 <hr><h3><a name="luaL_addsize"><code>luaL_addsize</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5366 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5367 <pre>void luaL_addsize (luaL_Buffer *B, size_t n);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5368 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5369 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5370 Adds to the buffer <code>B</code> (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5371 a string of length <code>n</code> previously copied to the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5372 buffer area (see <a href="#luaL_prepbuffer"><code>luaL_prepbuffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5373 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5374 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5375 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5376 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5377 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5378 <hr><h3><a name="luaL_addstring"><code>luaL_addstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5379 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5380 <pre>void luaL_addstring (luaL_Buffer *B, const char *s);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5381 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5382 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5383 Adds the zero-terminated string pointed to by <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5384 to the buffer <code>B</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5385 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5387 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5388 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5389 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5390 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5391 <hr><h3><a name="luaL_addvalue"><code>luaL_addvalue</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5392 <span class="apii">[-1, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5393 <pre>void luaL_addvalue (luaL_Buffer *B);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5394 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5395 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5396 Adds the value at the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5397 to the buffer <code>B</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5398 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5399 Pops the value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5400 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5402 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5403 This is the only function on string buffers that can (and must) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5404 be called with an extra element on the stack, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5405 which is the value to be added to the buffer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5406 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5407 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5408 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5409 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5410 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5411 <hr><h3><a name="luaL_argcheck"><code>luaL_argcheck</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5412 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5413 <pre>void luaL_argcheck (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5414 int cond, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5415 int arg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5416 const char *extramsg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5418 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5419 Checks whether <code>cond</code> is true. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5420 If it is not, raises an error with a standard message (see <a href="#luaL_argerror"><code>luaL_argerror</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5421 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5422 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5423 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5424 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5425 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5426 <hr><h3><a name="luaL_argerror"><code>luaL_argerror</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5427 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5428 <pre>int luaL_argerror (lua_State *L, int arg, const char *extramsg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5429 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5430 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5431 Raises an error reporting a problem with argument <code>arg</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5432 of the C function that called it, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5433 using a standard message |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5434 that includes <code>extramsg</code> as a comment: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5435 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5436 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5437 bad argument #<em>arg</em> to '<em>funcname</em>' (<em>extramsg</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5438 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5439 This function never returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5440 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5441 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5443 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5444 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5445 <hr><h3><a name="luaL_Buffer"><code>luaL_Buffer</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5446 <pre>typedef struct luaL_Buffer luaL_Buffer;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5448 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5449 Type for a <em>string buffer</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5450 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5451 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5452 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5453 A string buffer allows C code to build Lua strings piecemeal. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5454 Its pattern of use is as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5455 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5456 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5457 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5458 <li>First declare a variable <code>b</code> of type <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5459 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5460 <li>Then initialize it with a call <code>luaL_buffinit(L, &b)</code>.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5461 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5462 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5463 Then add string pieces to the buffer calling any of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5464 the <code>luaL_add*</code> functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5465 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5466 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5467 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5468 Finish by calling <code>luaL_pushresult(&b)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5469 This call leaves the final string on the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5470 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5472 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5473 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5474 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5475 If you know beforehand the total size of the resulting string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5476 you can use the buffer like this: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5477 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5478 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5479 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5480 <li>First declare a variable <code>b</code> of type <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5481 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5482 <li>Then initialize it and preallocate a space of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5483 size <code>sz</code> with a call <code>luaL_buffinitsize(L, &b, sz)</code>.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5484 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5485 <li>Then copy the string into that space.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5486 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5487 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5488 Finish by calling <code>luaL_pushresultsize(&b, sz)</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5489 where <code>sz</code> is the total size of the resulting string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5490 copied into that space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5491 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5492 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5493 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5494 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5495 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5496 During its normal operation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5497 a string buffer uses a variable number of stack slots. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5498 So, while using a buffer, you cannot assume that you know where |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5499 the top of the stack is. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5500 You can use the stack between successive calls to buffer operations |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5501 as long as that use is balanced; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5502 that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5503 when you call a buffer operation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5504 the stack is at the same level |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5505 it was immediately after the previous buffer operation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5506 (The only exception to this rule is <a href="#luaL_addvalue"><code>luaL_addvalue</code></a>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5507 After calling <a href="#luaL_pushresult"><code>luaL_pushresult</code></a> the stack is back to its |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5508 level when the buffer was initialized, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5509 plus the final string on its top. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5510 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5511 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5512 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5513 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5514 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5515 <hr><h3><a name="luaL_buffinit"><code>luaL_buffinit</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5516 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5517 <pre>void luaL_buffinit (lua_State *L, luaL_Buffer *B);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5518 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5519 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5520 Initializes a buffer <code>B</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5521 This function does not allocate any space; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5522 the buffer must be declared as a variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5523 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5524 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5526 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5527 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5528 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5529 <hr><h3><a name="luaL_buffinitsize"><code>luaL_buffinitsize</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5530 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5531 <pre>char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5532 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5533 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5534 Equivalent to the sequence |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5535 <a href="#luaL_buffinit"><code>luaL_buffinit</code></a>, <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5536 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5537 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5540 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5541 <hr><h3><a name="luaL_callmeta"><code>luaL_callmeta</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5542 <span class="apii">[-0, +(0|1), <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5543 <pre>int luaL_callmeta (lua_State *L, int obj, const char *e);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5544 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5545 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5546 Calls a metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5547 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5548 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5549 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5550 If the object at index <code>obj</code> has a metatable and this |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5551 metatable has a field <code>e</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5552 this function calls this field passing the object as its only argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5553 In this case this function returns true and pushes onto the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5554 stack the value returned by the call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5555 If there is no metatable or no metamethod, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5556 this function returns false (without pushing any value on the stack). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5557 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5558 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5559 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5561 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5562 <hr><h3><a name="luaL_checkany"><code>luaL_checkany</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5563 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5564 <pre>void luaL_checkany (lua_State *L, int arg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5566 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5567 Checks whether the function has an argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5568 of any type (including <b>nil</b>) at position <code>arg</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5569 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5570 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5571 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5572 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5573 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5574 <hr><h3><a name="luaL_checkinteger"><code>luaL_checkinteger</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5575 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5576 <pre>lua_Integer luaL_checkinteger (lua_State *L, int arg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5577 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5578 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5579 Checks whether the function argument <code>arg</code> is an integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5580 (or can be converted to an integer) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5581 and returns this integer cast to a <a href="#lua_Integer"><code>lua_Integer</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5582 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5583 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5584 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5585 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5586 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5587 <hr><h3><a name="luaL_checklstring"><code>luaL_checklstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5588 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5589 <pre>const char *luaL_checklstring (lua_State *L, int arg, size_t *l);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5590 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5591 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5592 Checks whether the function argument <code>arg</code> is a string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5593 and returns this string; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5594 if <code>l</code> is not <code>NULL</code> fills <code>*l</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5595 with the string's length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5596 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5597 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5598 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5599 This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5600 so all conversions and caveats of that function apply here. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5601 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5602 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5603 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5604 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5605 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5606 <hr><h3><a name="luaL_checknumber"><code>luaL_checknumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5607 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5608 <pre>lua_Number luaL_checknumber (lua_State *L, int arg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5609 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5610 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5611 Checks whether the function argument <code>arg</code> is a number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5612 and returns this number. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5614 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5615 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5616 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5617 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5618 <hr><h3><a name="luaL_checkoption"><code>luaL_checkoption</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5619 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5620 <pre>int luaL_checkoption (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5621 int arg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5622 const char *def, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5623 const char *const lst[]);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5624 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5625 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5626 Checks whether the function argument <code>arg</code> is a string and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5627 searches for this string in the array <code>lst</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5628 (which must be NULL-terminated). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5629 Returns the index in the array where the string was found. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5630 Raises an error if the argument is not a string or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5631 if the string cannot be found. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5632 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5633 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5634 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5635 If <code>def</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5636 the function uses <code>def</code> as a default value when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5637 there is no argument <code>arg</code> or when this argument is <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5638 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5639 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5640 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5641 This is a useful function for mapping strings to C enums. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5642 (The usual convention in Lua libraries is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5643 to use strings instead of numbers to select options.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5644 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5645 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5648 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5649 <hr><h3><a name="luaL_checkstack"><code>luaL_checkstack</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5650 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5651 <pre>void luaL_checkstack (lua_State *L, int sz, const char *msg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5652 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5653 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5654 Grows the stack size to <code>top + sz</code> elements, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5655 raising an error if the stack cannot grow to that size. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5656 <code>msg</code> is an additional text to go into the error message |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5657 (or <code>NULL</code> for no additional text). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5658 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5659 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5660 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5661 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5663 <hr><h3><a name="luaL_checkstring"><code>luaL_checkstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5664 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5665 <pre>const char *luaL_checkstring (lua_State *L, int arg);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5666 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5667 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5668 Checks whether the function argument <code>arg</code> is a string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5669 and returns this string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5670 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5671 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5672 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5673 This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5674 so all conversions and caveats of that function apply here. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5675 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5676 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5677 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5678 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5679 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5680 <hr><h3><a name="luaL_checktype"><code>luaL_checktype</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5681 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5682 <pre>void luaL_checktype (lua_State *L, int arg, int t);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5683 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5684 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5685 Checks whether the function argument <code>arg</code> has type <code>t</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5686 See <a href="#lua_type"><code>lua_type</code></a> for the encoding of types for <code>t</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5687 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5688 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5689 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5690 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5691 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5692 <hr><h3><a name="luaL_checkudata"><code>luaL_checkudata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5693 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5694 <pre>void *luaL_checkudata (lua_State *L, int arg, const char *tname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5696 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5697 Checks whether the function argument <code>arg</code> is a userdata |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5698 of the type <code>tname</code> (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>) and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5699 returns the userdata address (see <a href="#lua_touserdata"><code>lua_touserdata</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5700 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5701 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5702 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5703 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5704 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5705 <hr><h3><a name="luaL_checkversion"><code>luaL_checkversion</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5706 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5707 <pre>void luaL_checkversion (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5708 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5709 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5710 Checks whether the core running the call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5711 the core that created the Lua state, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5712 and the code making the call are all using the same version of Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5713 Also checks whether the core running the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5714 and the core that created the Lua state |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5715 are using the same address space. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5716 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5717 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5718 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5719 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5720 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5721 <hr><h3><a name="luaL_dofile"><code>luaL_dofile</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5722 <span class="apii">[-0, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5723 <pre>int luaL_dofile (lua_State *L, const char *filename);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5725 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5726 Loads and runs the given file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5727 It is defined as the following macro: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5728 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5729 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5730 (luaL_loadfile(L, filename) || lua_pcall(L, 0, LUA_MULTRET, 0)) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5731 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5732 It returns false if there are no errors |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5733 or true in case of errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5734 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5735 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5736 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5738 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5739 <hr><h3><a name="luaL_dostring"><code>luaL_dostring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5740 <span class="apii">[-0, +?, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5741 <pre>int luaL_dostring (lua_State *L, const char *str);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5742 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5743 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5744 Loads and runs the given string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5745 It is defined as the following macro: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5746 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5747 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5748 (luaL_loadstring(L, str) || lua_pcall(L, 0, LUA_MULTRET, 0)) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5749 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5750 It returns false if there are no errors |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5751 or true in case of errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5752 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5754 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5755 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5756 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5757 <hr><h3><a name="luaL_error"><code>luaL_error</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5758 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5759 <pre>int luaL_error (lua_State *L, const char *fmt, ...);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5760 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5761 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5762 Raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5763 The error message format is given by <code>fmt</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5764 plus any extra arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5765 following the same rules of <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5766 It also adds at the beginning of the message the file name and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5767 the line number where the error occurred, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5768 if this information is available. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5769 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5770 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5771 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5772 This function never returns, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5773 but it is an idiom to use it in C functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5774 as <code>return luaL_error(<em>args</em>)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5775 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5776 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5777 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5778 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5779 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5780 <hr><h3><a name="luaL_execresult"><code>luaL_execresult</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5781 <span class="apii">[-0, +3, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5782 <pre>int luaL_execresult (lua_State *L, int stat);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5783 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5784 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5785 This function produces the return values for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5786 process-related functions in the standard library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5787 (<a href="#pdf-os.execute"><code>os.execute</code></a> and <a href="#pdf-io.close"><code>io.close</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5788 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5789 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5790 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5792 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5793 <hr><h3><a name="luaL_fileresult"><code>luaL_fileresult</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5794 <span class="apii">[-0, +(1|3), <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5795 <pre>int luaL_fileresult (lua_State *L, int stat, const char *fname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5796 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5797 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5798 This function produces the return values for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5799 file-related functions in the standard library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5800 (<a href="#pdf-io.open"><code>io.open</code></a>, <a href="#pdf-os.rename"><code>os.rename</code></a>, <a href="#pdf-file:seek"><code>file:seek</code></a>, etc.). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5802 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5803 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5804 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5805 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5806 <hr><h3><a name="luaL_getmetafield"><code>luaL_getmetafield</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5807 <span class="apii">[-0, +(0|1), <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5808 <pre>int luaL_getmetafield (lua_State *L, int obj, const char *e);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5810 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5811 Pushes onto the stack the field <code>e</code> from the metatable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5812 of the object at index <code>obj</code> and returns the type of pushed value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5813 If the object does not have a metatable, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5814 or if the metatable does not have this field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5815 pushes nothing and returns <code>LUA_TNIL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5816 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5817 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5818 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5819 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5821 <hr><h3><a name="luaL_getmetatable"><code>luaL_getmetatable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5822 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5823 <pre>int luaL_getmetatable (lua_State *L, const char *tname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5824 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5825 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5826 Pushes onto the stack the metatable associated with name <code>tname</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5827 in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5828 If there is no metatable associated with <code>tname</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5829 returns false and pushes <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5830 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5831 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5833 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5834 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5835 <hr><h3><a name="luaL_getsubtable"><code>luaL_getsubtable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5836 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5837 <pre>int luaL_getsubtable (lua_State *L, int idx, const char *fname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5838 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5839 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5840 Ensures that the value <code>t[fname]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5841 where <code>t</code> is the value at index <code>idx</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5842 is a table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5843 and pushes that table onto the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5844 Returns true if it finds a previous table there |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5845 and false if it creates a new table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5846 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5847 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5848 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5849 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5850 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5851 <hr><h3><a name="luaL_gsub"><code>luaL_gsub</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5852 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5853 <pre>const char *luaL_gsub (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5854 const char *s, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5855 const char *p, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5856 const char *r);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5857 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5858 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5859 Creates a copy of string <code>s</code> by replacing |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5860 any occurrence of the string <code>p</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5861 with the string <code>r</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5862 Pushes the resulting string on the stack and returns it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5863 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5864 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5867 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5868 <hr><h3><a name="luaL_len"><code>luaL_len</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5869 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5870 <pre>lua_Integer luaL_len (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5871 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5872 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5873 Returns the "length" of the value at the given index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5874 as a number; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5875 it is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.7">§3.4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5876 Raises an error if the result of the operation is not an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5877 (This case only can happen through metamethods.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5878 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5879 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5880 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5881 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5882 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5883 <hr><h3><a name="luaL_loadbuffer"><code>luaL_loadbuffer</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5884 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5885 <pre>int luaL_loadbuffer (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5886 const char *buff, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5887 size_t sz, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5888 const char *name);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5889 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5890 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5891 Equivalent to <a href="#luaL_loadbufferx"><code>luaL_loadbufferx</code></a> with <code>mode</code> equal to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5892 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5893 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5894 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5895 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5896 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5897 <hr><h3><a name="luaL_loadbufferx"><code>luaL_loadbufferx</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5898 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5899 <pre>int luaL_loadbufferx (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5900 const char *buff, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5901 size_t sz, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5902 const char *name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5903 const char *mode);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5904 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5905 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5906 Loads a buffer as a Lua chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5907 This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5908 buffer pointed to by <code>buff</code> with size <code>sz</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5909 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5911 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5912 This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5913 <code>name</code> is the chunk name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5914 used for debug information and error messages. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5915 The string <code>mode</code> works as in function <a href="#lua_load"><code>lua_load</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5916 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5917 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5918 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5919 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5920 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5921 <hr><h3><a name="luaL_loadfile"><code>luaL_loadfile</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5922 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5923 <pre>int luaL_loadfile (lua_State *L, const char *filename);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5925 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5926 Equivalent to <a href="#luaL_loadfilex"><code>luaL_loadfilex</code></a> with <code>mode</code> equal to <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5927 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5928 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5929 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5930 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5931 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5932 <hr><h3><a name="luaL_loadfilex"><code>luaL_loadfilex</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5933 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5934 <pre>int luaL_loadfilex (lua_State *L, const char *filename, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5935 const char *mode);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5937 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5938 Loads a file as a Lua chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5939 This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the file |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5940 named <code>filename</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5941 If <code>filename</code> is <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5942 then it loads from the standard input. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5943 The first line in the file is ignored if it starts with a <code>#</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5944 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5945 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5946 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5947 The string <code>mode</code> works as in function <a href="#lua_load"><code>lua_load</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5948 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5949 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5950 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5951 This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5952 but it has an extra error code <a name="pdf-LUA_ERRFILE"><code>LUA_ERRFILE</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5953 if it cannot open/read the file or the file has a wrong mode. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5954 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5955 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5956 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5957 As <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5958 it does not run it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5959 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5960 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5961 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5962 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5964 <hr><h3><a name="luaL_loadstring"><code>luaL_loadstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5965 <span class="apii">[-0, +1, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5966 <pre>int luaL_loadstring (lua_State *L, const char *s);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5967 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5968 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5969 Loads a string as a Lua chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5970 This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5971 the zero-terminated string <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5972 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5973 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5974 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5975 This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5976 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5977 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5978 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5979 Also as <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5980 it does not run it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5981 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5982 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5983 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5984 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5986 <hr><h3><a name="luaL_newlib"><code>luaL_newlib</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5987 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5988 <pre>void luaL_newlib (lua_State *L, const luaL_Reg l[]);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5989 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5990 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5991 Creates a new table and registers there |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5992 the functions in list <code>l</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5995 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5996 It is implemented as the following macro: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5997 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5998 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
5999 (luaL_newlibtable(L,l), luaL_setfuncs(L,l,0)) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6000 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6001 The array <code>l</code> must be the actual array, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6002 not a pointer to it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6003 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6006 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6007 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6008 <hr><h3><a name="luaL_newlibtable"><code>luaL_newlibtable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6009 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6010 <pre>void luaL_newlibtable (lua_State *L, const luaL_Reg l[]);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6011 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6012 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6013 Creates a new table with a size optimized |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6014 to store all entries in the array <code>l</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6015 (but does not actually store them). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6016 It is intended to be used in conjunction with <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6017 (see <a href="#luaL_newlib"><code>luaL_newlib</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6019 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6020 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6021 It is implemented as a macro. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6022 The array <code>l</code> must be the actual array, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6023 not a pointer to it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6024 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6025 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6026 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6027 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6028 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6029 <hr><h3><a name="luaL_newmetatable"><code>luaL_newmetatable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6030 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6031 <pre>int luaL_newmetatable (lua_State *L, const char *tname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6033 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6034 If the registry already has the key <code>tname</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6035 returns 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6036 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6037 creates a new table to be used as a metatable for userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6038 adds to this new table the pair <code>__name = tname</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6039 adds to the registry the pair <code>[tname] = new table</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6040 and returns 1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6041 (The entry <code>__name</code> is used by some error-reporting functions.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6042 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6043 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6044 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6045 In both cases pushes onto the stack the final value associated |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6046 with <code>tname</code> in the registry. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6047 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6048 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6049 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6051 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6052 <hr><h3><a name="luaL_newstate"><code>luaL_newstate</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6053 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6054 <pre>lua_State *luaL_newstate (void);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6055 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6056 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6057 Creates a new Lua state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6058 It calls <a href="#lua_newstate"><code>lua_newstate</code></a> with an |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6059 allocator based on the standard C <code>realloc</code> function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6060 and then sets a panic function (see <a href="#4.6">§4.6</a>) that prints |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6061 an error message to the standard error output in case of fatal |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6062 errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6063 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6064 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6065 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6066 Returns the new state, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6067 or <code>NULL</code> if there is a memory allocation error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6068 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6069 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6070 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6072 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6073 <hr><h3><a name="luaL_openlibs"><code>luaL_openlibs</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6074 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6075 <pre>void luaL_openlibs (lua_State *L);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6076 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6077 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6078 Opens all standard Lua libraries into the given state. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6079 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6080 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6081 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6083 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6084 <hr><h3><a name="luaL_optinteger"><code>luaL_optinteger</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6085 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6086 <pre>lua_Integer luaL_optinteger (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6087 int arg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6088 lua_Integer d);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6089 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6090 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6091 If the function argument <code>arg</code> is an integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6092 (or convertible to an integer), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6093 returns this integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6094 If this argument is absent or is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6095 returns <code>d</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6096 Otherwise, raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6097 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6099 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6100 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6101 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6102 <hr><h3><a name="luaL_optlstring"><code>luaL_optlstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6103 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6104 <pre>const char *luaL_optlstring (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6105 int arg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6106 const char *d, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6107 size_t *l);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6109 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6110 If the function argument <code>arg</code> is a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6111 returns this string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6112 If this argument is absent or is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6113 returns <code>d</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6114 Otherwise, raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6115 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6116 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6117 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6118 If <code>l</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6119 fills the position <code>*l</code> with the result's length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6120 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6121 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6122 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6123 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6124 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6125 <hr><h3><a name="luaL_optnumber"><code>luaL_optnumber</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6126 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6127 <pre>lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number d);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6128 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6129 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6130 If the function argument <code>arg</code> is a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6131 returns this number. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6132 If this argument is absent or is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6133 returns <code>d</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6134 Otherwise, raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6135 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6136 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6137 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6138 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6139 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6140 <hr><h3><a name="luaL_optstring"><code>luaL_optstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6141 <span class="apii">[-0, +0, <em>v</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6142 <pre>const char *luaL_optstring (lua_State *L, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6143 int arg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6144 const char *d);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6145 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6146 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6147 If the function argument <code>arg</code> is a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6148 returns this string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6149 If this argument is absent or is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6150 returns <code>d</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6151 Otherwise, raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6152 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6153 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6154 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6156 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6157 <hr><h3><a name="luaL_prepbuffer"><code>luaL_prepbuffer</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6158 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6159 <pre>char *luaL_prepbuffer (luaL_Buffer *B);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6160 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6161 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6162 Equivalent to <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6163 with the predefined size <a name="pdf-LUAL_BUFFERSIZE"><code>LUAL_BUFFERSIZE</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6164 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6165 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6166 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6169 <hr><h3><a name="luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6170 <span class="apii">[-?, +?, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6171 <pre>char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6172 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6173 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6174 Returns an address to a space of size <code>sz</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6175 where you can copy a string to be added to buffer <code>B</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6176 (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6177 After copying the string into this space you must call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6178 <a href="#luaL_addsize"><code>luaL_addsize</code></a> with the size of the string to actually add |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6179 it to the buffer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6180 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6182 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6183 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6185 <hr><h3><a name="luaL_pushresult"><code>luaL_pushresult</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6186 <span class="apii">[-?, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6187 <pre>void luaL_pushresult (luaL_Buffer *B);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6188 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6189 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6190 Finishes the use of buffer <code>B</code> leaving the final string on |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6191 the top of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6192 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6193 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6194 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6195 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6196 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6197 <hr><h3><a name="luaL_pushresultsize"><code>luaL_pushresultsize</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6198 <span class="apii">[-?, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6199 <pre>void luaL_pushresultsize (luaL_Buffer *B, size_t sz);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6200 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6201 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6202 Equivalent to the sequence <a href="#luaL_addsize"><code>luaL_addsize</code></a>, <a href="#luaL_pushresult"><code>luaL_pushresult</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6203 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6204 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6206 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6207 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6208 <hr><h3><a name="luaL_ref"><code>luaL_ref</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6209 <span class="apii">[-1, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6210 <pre>int luaL_ref (lua_State *L, int t);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6211 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6212 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6213 Creates and returns a <em>reference</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6214 in the table at index <code>t</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6215 for the object at the top of the stack (and pops the object). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6216 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6218 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6219 A reference is a unique integer key. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6220 As long as you do not manually add integer keys into table <code>t</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6221 <a href="#luaL_ref"><code>luaL_ref</code></a> ensures the uniqueness of the key it returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6222 You can retrieve an object referred by reference <code>r</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6223 by calling <code>lua_rawgeti(L, t, r)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6224 Function <a href="#luaL_unref"><code>luaL_unref</code></a> frees a reference and its associated object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6225 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6226 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6227 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6228 If the object at the top of the stack is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6229 <a href="#luaL_ref"><code>luaL_ref</code></a> returns the constant <a name="pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6230 The constant <a name="pdf-LUA_NOREF"><code>LUA_NOREF</code></a> is guaranteed to be different |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6231 from any reference returned by <a href="#luaL_ref"><code>luaL_ref</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6232 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6233 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6234 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6237 <hr><h3><a name="luaL_Reg"><code>luaL_Reg</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6238 <pre>typedef struct luaL_Reg { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6239 const char *name; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6240 lua_CFunction func; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6241 } luaL_Reg;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6243 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6244 Type for arrays of functions to be registered by |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6245 <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6246 <code>name</code> is the function name and <code>func</code> is a pointer to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6247 the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6248 Any array of <a href="#luaL_Reg"><code>luaL_Reg</code></a> must end with a sentinel entry |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6249 in which both <code>name</code> and <code>func</code> are <code>NULL</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6250 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6251 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6252 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6255 <hr><h3><a name="luaL_requiref"><code>luaL_requiref</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6256 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6257 <pre>void luaL_requiref (lua_State *L, const char *modname, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6258 lua_CFunction openf, int glb);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6259 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6260 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6261 If <code>modname</code> is not already present in <a href="#pdf-package.loaded"><code>package.loaded</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6262 calls function <code>openf</code> with string <code>modname</code> as an argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6263 and sets the call result in <code>package.loaded[modname]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6264 as if that function has been called through <a href="#pdf-require"><code>require</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6267 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6268 If <code>glb</code> is true, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6269 also stores the module into global <code>modname</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6270 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6271 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6272 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6273 Leaves a copy of the module on the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6275 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6276 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6277 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6278 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6279 <hr><h3><a name="luaL_setfuncs"><code>luaL_setfuncs</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6280 <span class="apii">[-nup, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6281 <pre>void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6282 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6283 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6284 Registers all functions in the array <code>l</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6285 (see <a href="#luaL_Reg"><code>luaL_Reg</code></a>) into the table on the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6286 (below optional upvalues, see next). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6287 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6288 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6289 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6290 When <code>nup</code> is not zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6291 all functions are created sharing <code>nup</code> upvalues, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6292 which must be previously pushed on the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6293 on top of the library table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6294 These values are popped from the stack after the registration. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6295 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6296 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6297 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6298 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6300 <hr><h3><a name="luaL_setmetatable"><code>luaL_setmetatable</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6301 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6302 <pre>void luaL_setmetatable (lua_State *L, const char *tname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6303 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6304 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6305 Sets the metatable of the object at the top of the stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6306 as the metatable associated with name <code>tname</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6307 in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6308 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6309 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6310 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6311 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6312 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6313 <hr><h3><a name="luaL_Stream"><code>luaL_Stream</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6314 <pre>typedef struct luaL_Stream { |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6315 FILE *f; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6316 lua_CFunction closef; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6317 } luaL_Stream;</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6318 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6319 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6320 The standard representation for file handles, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6321 which is used by the standard I/O library. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6322 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6323 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6324 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6325 A file handle is implemented as a full userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6326 with a metatable called <code>LUA_FILEHANDLE</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6327 (where <code>LUA_FILEHANDLE</code> is a macro with the actual metatable's name). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6328 The metatable is created by the I/O library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6329 (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6330 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6331 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6332 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6333 This userdata must start with the structure <code>luaL_Stream</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6334 it can contain other data after this initial structure. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6335 Field <code>f</code> points to the corresponding C stream |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6336 (or it can be <code>NULL</code> to indicate an incompletely created handle). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6337 Field <code>closef</code> points to a Lua function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6338 that will be called to close the stream |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6339 when the handle is closed or collected; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6340 this function receives the file handle as its sole argument and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6341 must return either <b>true</b> (in case of success) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6342 or <b>nil</b> plus an error message (in case of error). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6343 Once Lua calls this field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6344 the field value is changed to <code>NULL</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6345 to signal that the handle is closed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6346 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6347 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6348 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6351 <hr><h3><a name="luaL_testudata"><code>luaL_testudata</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6352 <span class="apii">[-0, +0, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6353 <pre>void *luaL_testudata (lua_State *L, int arg, const char *tname);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6354 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6355 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6356 This function works like <a href="#luaL_checkudata"><code>luaL_checkudata</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6357 except that, when the test fails, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6358 it returns <code>NULL</code> instead of raising an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6359 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6360 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6361 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6362 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6363 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6364 <hr><h3><a name="luaL_tolstring"><code>luaL_tolstring</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6365 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6366 <pre>const char *luaL_tolstring (lua_State *L, int idx, size_t *len);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6367 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6368 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6369 Converts any Lua value at the given index to a C string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6370 in a reasonable format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6371 The resulting string is pushed onto the stack and also |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6372 returned by the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6373 If <code>len</code> is not <code>NULL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6374 the function also sets <code>*len</code> with the string length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6375 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6376 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6377 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6378 If the value has a metatable with a <code>"__tostring"</code> field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6379 then <code>luaL_tolstring</code> calls the corresponding metamethod |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6380 with the value as argument, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6381 and uses the result of the call as its result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6382 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6383 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6384 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6385 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6387 <hr><h3><a name="luaL_traceback"><code>luaL_traceback</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6388 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6389 <pre>void luaL_traceback (lua_State *L, lua_State *L1, const char *msg, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6390 int level);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6391 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6392 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6393 Creates and pushes a traceback of the stack <code>L1</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6394 If <code>msg</code> is not <code>NULL</code> it is appended |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6395 at the beginning of the traceback. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6396 The <code>level</code> parameter tells at which level |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6397 to start the traceback. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6398 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6399 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6400 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6403 <hr><h3><a name="luaL_typename"><code>luaL_typename</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6404 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6405 <pre>const char *luaL_typename (lua_State *L, int index);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6406 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6407 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6408 Returns the name of the type of the value at the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6409 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6410 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6411 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6412 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6413 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6414 <hr><h3><a name="luaL_unref"><code>luaL_unref</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6415 <span class="apii">[-0, +0, –]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6416 <pre>void luaL_unref (lua_State *L, int t, int ref);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6417 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6418 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6419 Releases reference <code>ref</code> from the table at index <code>t</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6420 (see <a href="#luaL_ref"><code>luaL_ref</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6421 The entry is removed from the table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6422 so that the referred object can be collected. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6423 The reference <code>ref</code> is also freed to be used again. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6424 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6425 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6426 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6427 If <code>ref</code> is <a href="#pdf-LUA_NOREF"><code>LUA_NOREF</code></a> or <a href="#pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6428 <a href="#luaL_unref"><code>luaL_unref</code></a> does nothing. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6429 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6430 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6431 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6432 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6433 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6434 <hr><h3><a name="luaL_where"><code>luaL_where</code></a></h3><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6435 <span class="apii">[-0, +1, <em>e</em>]</span> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6436 <pre>void luaL_where (lua_State *L, int lvl);</pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6437 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6438 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6439 Pushes onto the stack a string identifying the current position |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6440 of the control at level <code>lvl</code> in the call stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6441 Typically this string has the following format: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6443 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6444 <em>chunkname</em>:<em>currentline</em>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6445 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6446 Level 0 is the running function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6447 level 1 is the function that called the running function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6448 etc. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6449 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6450 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6451 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6452 This function is used to build a prefix for error messages. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6453 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6454 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6455 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6456 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6457 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6458 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6459 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6460 <h1>6 – <a name="6">Standard Libraries</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6461 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6462 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6463 The standard Lua libraries provide useful functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6464 that are implemented directly through the C API. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6465 Some of these functions provide essential services to the language |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6466 (e.g., <a href="#pdf-type"><code>type</code></a> and <a href="#pdf-getmetatable"><code>getmetatable</code></a>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6467 others provide access to "outside" services (e.g., I/O); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6468 and others could be implemented in Lua itself, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6469 but are quite useful or have critical performance requirements that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6470 deserve an implementation in C (e.g., <a href="#pdf-table.sort"><code>table.sort</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6472 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6473 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6474 All libraries are implemented through the official C API |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6475 and are provided as separate C modules. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6476 Currently, Lua has the following standard libraries: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6477 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6478 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6479 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6480 <li>basic library (<a href="#6.1">§6.1</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6481 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6482 <li>coroutine library (<a href="#6.2">§6.2</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6484 <li>package library (<a href="#6.3">§6.3</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6485 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6486 <li>string manipulation (<a href="#6.4">§6.4</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6487 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6488 <li>basic UTF-8 support (<a href="#6.5">§6.5</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6489 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6490 <li>table manipulation (<a href="#6.6">§6.6</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6491 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6492 <li>mathematical functions (<a href="#6.7">§6.7</a>) (sin, log, etc.);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6493 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6494 <li>input and output (<a href="#6.8">§6.8</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6495 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6496 <li>operating system facilities (<a href="#6.9">§6.9</a>);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6497 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6498 <li>debug facilities (<a href="#6.10">§6.10</a>).</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6499 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6500 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6501 Except for the basic and the package libraries, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6502 each library provides all its functions as fields of a global table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6503 or as methods of its objects. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6504 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6505 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6506 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6507 To have access to these libraries, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6508 the C host program should call the <a href="#luaL_openlibs"><code>luaL_openlibs</code></a> function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6509 which opens all standard libraries. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6510 Alternatively, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6511 the host program can open them individually by using |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6512 <a href="#luaL_requiref"><code>luaL_requiref</code></a> to call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6513 <a name="pdf-luaopen_base"><code>luaopen_base</code></a> (for the basic library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6514 <a name="pdf-luaopen_package"><code>luaopen_package</code></a> (for the package library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6515 <a name="pdf-luaopen_coroutine"><code>luaopen_coroutine</code></a> (for the coroutine library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6516 <a name="pdf-luaopen_string"><code>luaopen_string</code></a> (for the string library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6517 <a name="pdf-luaopen_utf8"><code>luaopen_utf8</code></a> (for the UTF8 library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6518 <a name="pdf-luaopen_table"><code>luaopen_table</code></a> (for the table library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6519 <a name="pdf-luaopen_math"><code>luaopen_math</code></a> (for the mathematical library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6520 <a name="pdf-luaopen_io"><code>luaopen_io</code></a> (for the I/O library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6521 <a name="pdf-luaopen_os"><code>luaopen_os</code></a> (for the operating system library), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6522 and <a name="pdf-luaopen_debug"><code>luaopen_debug</code></a> (for the debug library). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6523 These functions are declared in <a name="pdf-lualib.h"><code>lualib.h</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6524 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6526 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6527 <h2>6.1 – <a name="6.1">Basic Functions</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6528 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6529 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6530 The basic library provides core functions to Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6531 If you do not include this library in your application, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6532 you should check carefully whether you need to provide |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6533 implementations for some of its facilities. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6534 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6535 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6536 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6537 <hr><h3><a name="pdf-assert"><code>assert (v [, message])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6540 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6541 Calls <a href="#pdf-error"><code>error</code></a> if |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6542 the value of its argument <code>v</code> is false (i.e., <b>nil</b> or <b>false</b>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6543 otherwise, returns all its arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6544 In case of error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6545 <code>message</code> is the error object; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6546 when absent, it defaults to "<code>assertion failed!</code>" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6547 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6548 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6549 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6550 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6551 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6552 <hr><h3><a name="pdf-collectgarbage"><code>collectgarbage ([opt [, arg]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6553 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6554 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6555 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6556 This function is a generic interface to the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6557 It performs different functions according to its first argument, <code>opt</code>: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6558 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6559 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6561 <li><b>"<code>collect</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6562 performs a full garbage-collection cycle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6563 This is the default option. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6564 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6566 <li><b>"<code>stop</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6567 stops automatic execution of the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6568 The collector will run only when explicitly invoked, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6569 until a call to restart it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6570 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6571 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6572 <li><b>"<code>restart</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6573 restarts automatic execution of the garbage collector. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6574 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6575 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6576 <li><b>"<code>count</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6577 returns the total memory in use by Lua in Kbytes. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6578 The value has a fractional part, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6579 so that it multiplied by 1024 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6580 gives the exact number of bytes in use by Lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6581 (except for overflows). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6582 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6583 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6584 <li><b>"<code>step</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6585 performs a garbage-collection step. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6586 The step "size" is controlled by <code>arg</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6587 With a zero value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6588 the collector will perform one basic (indivisible) step. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6589 For non-zero values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6590 the collector will perform as if that amount of memory |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6591 (in KBytes) had been allocated by Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6592 Returns <b>true</b> if the step finished a collection cycle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6593 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6594 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6595 <li><b>"<code>setpause</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6596 sets <code>arg</code> as the new value for the <em>pause</em> of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6597 the collector (see <a href="#2.5">§2.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6598 Returns the previous value for <em>pause</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6599 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6600 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6601 <li><b>"<code>setstepmul</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6602 sets <code>arg</code> as the new value for the <em>step multiplier</em> of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6603 the collector (see <a href="#2.5">§2.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6604 Returns the previous value for <em>step</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6605 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6607 <li><b>"<code>isrunning</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6608 returns a boolean that tells whether the collector is running |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6609 (i.e., not stopped). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6610 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6611 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6612 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6614 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6615 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6616 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6617 <hr><h3><a name="pdf-dofile"><code>dofile ([filename])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6618 Opens the named file and executes its contents as a Lua chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6619 When called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6620 <code>dofile</code> executes the contents of the standard input (<code>stdin</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6621 Returns all values returned by the chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6622 In case of errors, <code>dofile</code> propagates the error |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6623 to its caller (that is, <code>dofile</code> does not run in protected mode). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6624 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6625 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6626 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6627 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6628 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6629 <hr><h3><a name="pdf-error"><code>error (message [, level])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6630 Terminates the last protected function called |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6631 and returns <code>message</code> as the error object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6632 Function <code>error</code> never returns. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6633 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6634 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6635 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6636 Usually, <code>error</code> adds some information about the error position |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6637 at the beginning of the message, if the message is a string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6638 The <code>level</code> argument specifies how to get the error position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6639 With level 1 (the default), the error position is where the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6640 <code>error</code> function was called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6641 Level 2 points the error to where the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6642 that called <code>error</code> was called; and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6643 Passing a level 0 avoids the addition of error position information |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6644 to the message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6645 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6648 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6649 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6650 <hr><h3><a name="pdf-_G"><code>_G</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6651 A global variable (not a function) that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6652 holds the global environment (see <a href="#2.2">§2.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6653 Lua itself does not use this variable; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6654 changing its value does not affect any environment, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6655 nor vice versa. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6656 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6657 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6658 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6659 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6660 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6661 <hr><h3><a name="pdf-getmetatable"><code>getmetatable (object)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6663 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6664 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6665 If <code>object</code> does not have a metatable, returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6666 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6667 if the object's metatable has a <code>"__metatable"</code> field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6668 returns the associated value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6669 Otherwise, returns the metatable of the given object. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6670 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6671 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6672 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6673 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6674 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6675 <hr><h3><a name="pdf-ipairs"><code>ipairs (t)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6676 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6677 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6678 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6679 Returns three values (an iterator function, the table <code>t</code>, and 0) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6680 so that the construction |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6681 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6682 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6683 for i,v in ipairs(t) do <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6684 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6685 will iterate over the key–value pairs |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6686 (<code>1,t[1]</code>), (<code>2,t[2]</code>), ..., |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6687 up to the first nil value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6688 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6689 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6690 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6691 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6692 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6693 <hr><h3><a name="pdf-load"><code>load (chunk [, chunkname [, mode [, env]]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6694 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6696 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6697 Loads a chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6698 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6699 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6700 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6701 If <code>chunk</code> is a string, the chunk is this string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6702 If <code>chunk</code> is a function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6703 <code>load</code> calls it repeatedly to get the chunk pieces. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6704 Each call to <code>chunk</code> must return a string that concatenates |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6705 with previous results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6706 A return of an empty string, <b>nil</b>, or no value signals the end of the chunk. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6707 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6708 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6709 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6710 If there are no syntactic errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6711 returns the compiled chunk as a function; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6712 otherwise, returns <b>nil</b> plus the error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6713 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6714 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6715 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6716 If the resulting function has upvalues, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6717 the first upvalue is set to the value of <code>env</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6718 if that parameter is given, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6719 or to the value of the global environment. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6720 Other upvalues are initialized with <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6721 (When you load a main chunk, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6722 the resulting function will always have exactly one upvalue, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6723 the <code>_ENV</code> variable (see <a href="#2.2">§2.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6724 However, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6725 when you load a binary chunk created from a function (see <a href="#pdf-string.dump"><code>string.dump</code></a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6726 the resulting function can have an arbitrary number of upvalues.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6727 All upvalues are fresh, that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6728 they are not shared with any other function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6729 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6730 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6731 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6732 <code>chunkname</code> is used as the name of the chunk for error messages |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6733 and debug information (see <a href="#4.9">§4.9</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6734 When absent, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6735 it defaults to <code>chunk</code>, if <code>chunk</code> is a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6736 or to "<code>=(load)</code>" otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6738 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6739 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6740 The string <code>mode</code> controls whether the chunk can be text or binary |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6741 (that is, a precompiled chunk). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6742 It may be the string "<code>b</code>" (only binary chunks), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6743 "<code>t</code>" (only text chunks), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6744 or "<code>bt</code>" (both binary and text). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6745 The default is "<code>bt</code>". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6746 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6747 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6748 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6749 Lua does not check the consistency of binary chunks. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6750 Maliciously crafted binary chunks can crash |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6751 the interpreter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6752 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6754 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6755 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6756 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6757 <hr><h3><a name="pdf-loadfile"><code>loadfile ([filename [, mode [, env]]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6758 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6759 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6760 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6761 Similar to <a href="#pdf-load"><code>load</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6762 but gets the chunk from file <code>filename</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6763 or from the standard input, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6764 if no file name is given. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6765 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6766 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6767 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6768 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6769 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6770 <hr><h3><a name="pdf-next"><code>next (table [, index])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6771 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6772 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6773 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6774 Allows a program to traverse all fields of a table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6775 Its first argument is a table and its second argument |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6776 is an index in this table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6777 <code>next</code> returns the next index of the table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6778 and its associated value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6779 When called with <b>nil</b> as its second argument, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6780 <code>next</code> returns an initial index |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6781 and its associated value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6782 When called with the last index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6783 or with <b>nil</b> in an empty table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6784 <code>next</code> returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6785 If the second argument is absent, then it is interpreted as <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6786 In particular, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6787 you can use <code>next(t)</code> to check whether a table is empty. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6788 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6789 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6790 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6791 The order in which the indices are enumerated is not specified, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6792 <em>even for numeric indices</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6793 (To traverse a table in numeric order, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6794 use a numerical <b>for</b>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6795 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6796 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6797 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6798 The behavior of <code>next</code> is undefined if, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6799 during the traversal, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6800 you assign any value to a non-existent field in the table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6801 You may however modify existing fields. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6802 In particular, you may clear existing fields. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6803 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6804 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6805 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6807 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6808 <hr><h3><a name="pdf-pairs"><code>pairs (t)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6810 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6811 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6812 If <code>t</code> has a metamethod <code>__pairs</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6813 calls it with <code>t</code> as argument and returns the first three |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6814 results from the call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6815 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6816 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6817 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6818 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6819 returns three values: the <a href="#pdf-next"><code>next</code></a> function, the table <code>t</code>, and <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6820 so that the construction |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6822 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6823 for k,v in pairs(t) do <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6824 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6825 will iterate over all key–value pairs of table <code>t</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6826 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6827 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6828 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6829 See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6830 the table during its traversal. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6831 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6833 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6834 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6835 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6836 <hr><h3><a name="pdf-pcall"><code>pcall (f [, arg1, ···])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6837 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6838 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6839 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6840 Calls function <code>f</code> with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6841 the given arguments in <em>protected mode</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6842 This means that any error inside <code>f</code> is not propagated; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6843 instead, <code>pcall</code> catches the error |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6844 and returns a status code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6845 Its first result is the status code (a boolean), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6846 which is true if the call succeeds without errors. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6847 In such case, <code>pcall</code> also returns all results from the call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6848 after this first result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6849 In case of any error, <code>pcall</code> returns <b>false</b> plus the error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6850 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6851 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6852 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6853 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6854 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6855 <hr><h3><a name="pdf-print"><code>print (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6856 Receives any number of arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6857 and prints their values to <code>stdout</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6858 using the <a href="#pdf-tostring"><code>tostring</code></a> function to convert each argument to a string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6859 <code>print</code> is not intended for formatted output, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6860 but only as a quick way to show a value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6861 for instance for debugging. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6862 For complete control over the output, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6863 use <a href="#pdf-string.format"><code>string.format</code></a> and <a href="#pdf-io.write"><code>io.write</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6864 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6867 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6868 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6869 <hr><h3><a name="pdf-rawequal"><code>rawequal (v1, v2)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6870 Checks whether <code>v1</code> is equal to <code>v2</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6871 without invoking any metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6872 Returns a boolean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6873 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6874 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6875 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6876 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6877 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6878 <hr><h3><a name="pdf-rawget"><code>rawget (table, index)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6879 Gets the real value of <code>table[index]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6880 without invoking any metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6881 <code>table</code> must be a table; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6882 <code>index</code> may be any value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6883 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6884 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6885 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6886 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6887 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6888 <hr><h3><a name="pdf-rawlen"><code>rawlen (v)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6889 Returns the length of the object <code>v</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6890 which must be a table or a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6891 without invoking any metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6892 Returns an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6893 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6894 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6895 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6896 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6897 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6898 <hr><h3><a name="pdf-rawset"><code>rawset (table, index, value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6899 Sets the real value of <code>table[index]</code> to <code>value</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6900 without invoking any metamethod. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6901 <code>table</code> must be a table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6902 <code>index</code> any value different from <b>nil</b> and NaN, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6903 and <code>value</code> any Lua value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6904 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6905 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6906 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6907 This function returns <code>table</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6908 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6909 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6911 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6912 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6913 <hr><h3><a name="pdf-select"><code>select (index, ···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6914 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6915 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6916 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6917 If <code>index</code> is a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6918 returns all arguments after argument number <code>index</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6919 a negative number indexes from the end (-1 is the last argument). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6920 Otherwise, <code>index</code> must be the string <code>"#"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6921 and <code>select</code> returns the total number of extra arguments it received. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6923 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6925 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6926 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6927 <hr><h3><a name="pdf-setmetatable"><code>setmetatable (table, metatable)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6928 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6929 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6930 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6931 Sets the metatable for the given table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6932 (You cannot change the metatable of other types from Lua, only from C.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6933 If <code>metatable</code> is <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6934 removes the metatable of the given table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6935 If the original metatable has a <code>"__metatable"</code> field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6936 raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6937 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6938 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6939 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6940 This function returns <code>table</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6941 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6942 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6943 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6944 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6945 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6946 <hr><h3><a name="pdf-tonumber"><code>tonumber (e [, base])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6947 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6948 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6949 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6950 When called with no <code>base</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6951 <code>tonumber</code> tries to convert its argument to a number. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6952 If the argument is already a number or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6953 a string convertible to a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6954 then <code>tonumber</code> returns this number; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6955 otherwise, it returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6956 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6957 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6958 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6959 The conversion of strings can result in integers or floats, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6960 according to the lexical conventions of Lua (see <a href="#3.1">§3.1</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6961 (The string may have leading and trailing spaces and a sign.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6962 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6964 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6965 When called with <code>base</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6966 then <code>e</code> must be a string to be interpreted as |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6967 an integer numeral in that base. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6968 The base may be any integer between 2 and 36, inclusive. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6969 In bases above 10, the letter '<code>A</code>' (in either upper or lower case) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6970 represents 10, '<code>B</code>' represents 11, and so forth, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6971 with '<code>Z</code>' representing 35. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6972 If the string <code>e</code> is not a valid numeral in the given base, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6973 the function returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6974 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6975 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6976 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6977 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6978 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6979 <hr><h3><a name="pdf-tostring"><code>tostring (v)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6980 Receives a value of any type and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6981 converts it to a string in a human-readable format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6982 Floats always produce strings with some |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6983 floating-point indication (either a decimal dot or an exponent). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6984 (For complete control of how numbers are converted, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6985 use <a href="#pdf-string.format"><code>string.format</code></a>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6986 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6987 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6988 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6989 If the metatable of <code>v</code> has a <code>"__tostring"</code> field, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6990 then <code>tostring</code> calls the corresponding value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6991 with <code>v</code> as argument, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6992 and uses the result of the call as its result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6995 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6996 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6997 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6998 <hr><h3><a name="pdf-type"><code>type (v)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
6999 Returns the type of its only argument, coded as a string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7000 The possible results of this function are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7001 "<code>nil</code>" (a string, not the value <b>nil</b>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7002 "<code>number</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7003 "<code>string</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7004 "<code>boolean</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7005 "<code>table</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7006 "<code>function</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7007 "<code>thread</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7008 and "<code>userdata</code>". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7009 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7010 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7011 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7012 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7013 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7014 <hr><h3><a name="pdf-_VERSION"><code>_VERSION</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7015 A global variable (not a function) that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7016 holds a string containing the current interpreter version. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7017 The current value of this variable is "<code>Lua 5.3</code>". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7019 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7020 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7021 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7022 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7023 <hr><h3><a name="pdf-xpcall"><code>xpcall (f, msgh [, arg1, ···])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7024 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7025 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7026 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7027 This function is similar to <a href="#pdf-pcall"><code>pcall</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7028 except that it sets a new message handler <code>msgh</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7029 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7030 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7031 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7034 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7035 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7036 <h2>6.2 – <a name="6.2">Coroutine Manipulation</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7037 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7038 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7039 The operations related to coroutines comprise a sub-library of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7040 the basic library and come inside the table <a name="pdf-coroutine"><code>coroutine</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7041 See <a href="#2.6">§2.6</a> for a general description of coroutines. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7042 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7043 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7044 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7045 <hr><h3><a name="pdf-coroutine.create"><code>coroutine.create (f)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7046 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7047 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7048 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7049 Creates a new coroutine, with body <code>f</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7050 <code>f</code> must be a Lua function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7051 Returns this new coroutine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7052 an object with type <code>"thread"</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7053 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7054 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7055 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7057 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7058 <hr><h3><a name="pdf-coroutine.isyieldable"><code>coroutine.isyieldable ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7059 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7060 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7061 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7062 Returns true when the running coroutine can yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7063 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7064 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7065 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7066 A running coroutine is yieldable if it is not the main thread and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7067 it is not inside a non-yieldable C function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7068 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7069 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7070 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7072 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7073 <hr><h3><a name="pdf-coroutine.resume"><code>coroutine.resume (co [, val1, ···])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7074 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7075 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7076 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7077 Starts or continues the execution of coroutine <code>co</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7078 The first time you resume a coroutine, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7079 it starts running its body. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7080 The values <code>val1</code>, ... are passed |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7081 as the arguments to the body function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7082 If the coroutine has yielded, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7083 <code>resume</code> restarts it; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7084 the values <code>val1</code>, ... are passed |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7085 as the results from the yield. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7086 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7087 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7088 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7089 If the coroutine runs without any errors, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7090 <code>resume</code> returns <b>true</b> plus any values passed to <code>yield</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7091 (when the coroutine yields) or any values returned by the body function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7092 (when the coroutine terminates). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7093 If there is any error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7094 <code>resume</code> returns <b>false</b> plus the error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7095 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7096 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7097 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7099 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7100 <hr><h3><a name="pdf-coroutine.running"><code>coroutine.running ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7101 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7102 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7103 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7104 Returns the running coroutine plus a boolean, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7105 true when the running coroutine is the main one. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7106 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7109 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7110 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7111 <hr><h3><a name="pdf-coroutine.status"><code>coroutine.status (co)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7112 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7113 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7114 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7115 Returns the status of coroutine <code>co</code>, as a string: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7116 <code>"running"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7117 if the coroutine is running (that is, it called <code>status</code>); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7118 <code>"suspended"</code>, if the coroutine is suspended in a call to <code>yield</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7119 or if it has not started running yet; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7120 <code>"normal"</code> if the coroutine is active but not running |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7121 (that is, it has resumed another coroutine); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7122 and <code>"dead"</code> if the coroutine has finished its body function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7123 or if it has stopped with an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7124 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7125 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7126 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7127 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7128 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7129 <hr><h3><a name="pdf-coroutine.wrap"><code>coroutine.wrap (f)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7130 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7131 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7132 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7133 Creates a new coroutine, with body <code>f</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7134 <code>f</code> must be a Lua function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7135 Returns a function that resumes the coroutine each time it is called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7136 Any arguments passed to the function behave as the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7137 extra arguments to <code>resume</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7138 Returns the same values returned by <code>resume</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7139 except the first boolean. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7140 In case of error, propagates the error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7144 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7145 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7146 <hr><h3><a name="pdf-coroutine.yield"><code>coroutine.yield (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7147 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7148 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7149 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7150 Suspends the execution of the calling coroutine. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7151 Any arguments to <code>yield</code> are passed as extra results to <code>resume</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7152 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7153 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7154 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7156 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7157 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7158 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7159 <h2>6.3 – <a name="6.3">Modules</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7160 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7161 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7162 The package library provides basic |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7163 facilities for loading modules in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7164 It exports one function directly in the global environment: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7165 <a href="#pdf-require"><code>require</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7166 Everything else is exported in a table <a name="pdf-package"><code>package</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7169 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7170 <hr><h3><a name="pdf-require"><code>require (modname)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7171 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7172 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7173 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7174 Loads the given module. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7175 The function starts by looking into the <a href="#pdf-package.loaded"><code>package.loaded</code></a> table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7176 to determine whether <code>modname</code> is already loaded. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7177 If it is, then <code>require</code> returns the value stored |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7178 at <code>package.loaded[modname]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7179 Otherwise, it tries to find a <em>loader</em> for the module. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7180 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7181 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7182 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7183 To find a loader, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7184 <code>require</code> is guided by the <a href="#pdf-package.searchers"><code>package.searchers</code></a> sequence. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7185 By changing this sequence, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7186 we can change how <code>require</code> looks for a module. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7187 The following explanation is based on the default configuration |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7188 for <a href="#pdf-package.searchers"><code>package.searchers</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7190 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7191 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7192 First <code>require</code> queries <code>package.preload[modname]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7193 If it has a value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7194 this value (which must be a function) is the loader. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7195 Otherwise <code>require</code> searches for a Lua loader using the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7196 path stored in <a href="#pdf-package.path"><code>package.path</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7197 If that also fails, it searches for a C loader using the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7198 path stored in <a href="#pdf-package.cpath"><code>package.cpath</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7199 If that also fails, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7200 it tries an <em>all-in-one</em> loader (see <a href="#pdf-package.searchers"><code>package.searchers</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7202 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7203 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7204 Once a loader is found, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7205 <code>require</code> calls the loader with two arguments: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7206 <code>modname</code> and an extra value dependent on how it got the loader. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7207 (If the loader came from a file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7208 this extra value is the file name.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7209 If the loader returns any non-nil value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7210 <code>require</code> assigns the returned value to <code>package.loaded[modname]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7211 If the loader does not return a non-nil value and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7212 has not assigned any value to <code>package.loaded[modname]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7213 then <code>require</code> assigns <b>true</b> to this entry. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7214 In any case, <code>require</code> returns the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7215 final value of <code>package.loaded[modname]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7216 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7218 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7219 If there is any error loading or running the module, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7220 or if it cannot find any loader for the module, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7221 then <code>require</code> raises an error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7222 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7223 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7224 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7225 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7226 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7227 <hr><h3><a name="pdf-package.config"><code>package.config</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7228 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7229 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7230 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7231 A string describing some compile-time configurations for packages. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7232 This string is a sequence of lines: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7233 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7234 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7236 <li>The first line is the directory separator string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7237 Default is '<code>\</code>' for Windows and '<code>/</code>' for all other systems.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7238 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7239 <li>The second line is the character that separates templates in a path. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7240 Default is '<code>;</code>'.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7242 <li>The third line is the string that marks the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7243 substitution points in a template. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7244 Default is '<code>?</code>'.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7245 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7246 <li>The fourth line is a string that, in a path in Windows, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7247 is replaced by the executable's directory. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7248 Default is '<code>!</code>'.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7249 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7250 <li>The fifth line is a mark to ignore all text after it |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7251 when building the <code>luaopen_</code> function name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7252 Default is '<code>-</code>'.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7254 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7255 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7256 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7257 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7258 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7259 <hr><h3><a name="pdf-package.cpath"><code>package.cpath</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7260 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7261 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7262 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7263 The path used by <a href="#pdf-require"><code>require</code></a> to search for a C loader. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7264 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7266 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7267 Lua initializes the C path <a href="#pdf-package.cpath"><code>package.cpath</code></a> in the same way |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7268 it initializes the Lua path <a href="#pdf-package.path"><code>package.path</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7269 using the environment variable <a name="pdf-LUA_CPATH_5_3"><code>LUA_CPATH_5_3</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7270 or the environment variable <a name="pdf-LUA_CPATH"><code>LUA_CPATH</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7271 or a default path defined in <code>luaconf.h</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7272 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7273 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7275 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7276 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7277 <hr><h3><a name="pdf-package.loaded"><code>package.loaded</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7278 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7279 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7280 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7281 A table used by <a href="#pdf-require"><code>require</code></a> to control which |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7282 modules are already loaded. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7283 When you require a module <code>modname</code> and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7284 <code>package.loaded[modname]</code> is not false, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7285 <a href="#pdf-require"><code>require</code></a> simply returns the value stored there. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7286 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7287 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7288 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7289 This variable is only a reference to the real table; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7290 assignments to this variable do not change the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7291 table used by <a href="#pdf-require"><code>require</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7292 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7293 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7294 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7295 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7296 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7297 <hr><h3><a name="pdf-package.loadlib"><code>package.loadlib (libname, funcname)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7298 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7300 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7301 Dynamically links the host program with the C library <code>libname</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7302 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7303 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7304 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7305 If <code>funcname</code> is "<code>*</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7306 then it only links with the library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7307 making the symbols exported by the library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7308 available to other dynamically linked libraries. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7309 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7310 it looks for a function <code>funcname</code> inside the library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7311 and returns this function as a C function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7312 So, <code>funcname</code> must follow the <a href="#lua_CFunction"><code>lua_CFunction</code></a> prototype |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7313 (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7314 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7315 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7316 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7317 This is a low-level function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7318 It completely bypasses the package and module system. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7319 Unlike <a href="#pdf-require"><code>require</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7320 it does not perform any path searching and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7321 does not automatically adds extensions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7322 <code>libname</code> must be the complete file name of the C library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7323 including if necessary a path and an extension. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7324 <code>funcname</code> must be the exact name exported by the C library |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7325 (which may depend on the C compiler and linker used). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7326 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7327 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7328 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7329 This function is not supported by Standard C. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7330 As such, it is only available on some platforms |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7331 (Windows, Linux, Mac OS X, Solaris, BSD, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7332 plus other Unix systems that support the <code>dlfcn</code> standard). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7333 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7334 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7335 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7336 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7337 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7338 <hr><h3><a name="pdf-package.path"><code>package.path</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7339 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7340 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7341 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7342 The path used by <a href="#pdf-require"><code>require</code></a> to search for a Lua loader. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7343 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7344 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7345 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7346 At start-up, Lua initializes this variable with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7347 the value of the environment variable <a name="pdf-LUA_PATH_5_3"><code>LUA_PATH_5_3</code></a> or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7348 the environment variable <a name="pdf-LUA_PATH"><code>LUA_PATH</code></a> or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7349 with a default path defined in <code>luaconf.h</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7350 if those environment variables are not defined. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7351 Any "<code>;;</code>" in the value of the environment variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7352 is replaced by the default path. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7353 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7354 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7355 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7357 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7358 <hr><h3><a name="pdf-package.preload"><code>package.preload</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7359 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7360 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7361 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7362 A table to store loaders for specific modules |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7363 (see <a href="#pdf-require"><code>require</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7365 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7366 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7367 This variable is only a reference to the real table; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7368 assignments to this variable do not change the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7369 table used by <a href="#pdf-require"><code>require</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7370 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7371 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7372 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7373 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7374 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7375 <hr><h3><a name="pdf-package.searchers"><code>package.searchers</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7376 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7377 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7378 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7379 A table used by <a href="#pdf-require"><code>require</code></a> to control how to load modules. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7380 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7381 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7382 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7383 Each entry in this table is a <em>searcher function</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7384 When looking for a module, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7385 <a href="#pdf-require"><code>require</code></a> calls each of these searchers in ascending order, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7386 with the module name (the argument given to <a href="#pdf-require"><code>require</code></a>) as its |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7387 sole parameter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7388 The function can return another function (the module <em>loader</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7389 plus an extra value that will be passed to that loader, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7390 or a string explaining why it did not find that module |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7391 (or <b>nil</b> if it has nothing to say). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7392 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7393 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7394 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7395 Lua initializes this table with four searcher functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7396 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7397 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7398 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7399 The first searcher simply looks for a loader in the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7400 <a href="#pdf-package.preload"><code>package.preload</code></a> table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7403 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7404 The second searcher looks for a loader as a Lua library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7405 using the path stored at <a href="#pdf-package.path"><code>package.path</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7406 The search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7407 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7408 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7409 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7410 The third searcher looks for a loader as a C library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7411 using the path given by the variable <a href="#pdf-package.cpath"><code>package.cpath</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7412 Again, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7413 the search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7414 For instance, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7415 if the C path is the string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7416 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7417 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7418 "./?.so;./?.dll;/usr/local/?/init.so" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7419 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7420 the searcher for module <code>foo</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7421 will try to open the files <code>./foo.so</code>, <code>./foo.dll</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7422 and <code>/usr/local/foo/init.so</code>, in that order. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7423 Once it finds a C library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7424 this searcher first uses a dynamic link facility to link the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7425 application with the library. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7426 Then it tries to find a C function inside the library to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7427 be used as the loader. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7428 The name of this C function is the string "<code>luaopen_</code>" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7429 concatenated with a copy of the module name where each dot |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7430 is replaced by an underscore. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7431 Moreover, if the module name has a hyphen, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7432 its suffix after (and including) the first hyphen is removed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7433 For instance, if the module name is <code>a.b.c-v2.1</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7434 the function name will be <code>luaopen_a_b_c</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7435 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7436 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7437 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7438 The fourth searcher tries an <em>all-in-one loader</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7439 It searches the C path for a library for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7440 the root name of the given module. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7441 For instance, when requiring <code>a.b.c</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7442 it will search for a C library for <code>a</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7443 If found, it looks into it for an open function for |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7444 the submodule; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7445 in our example, that would be <code>luaopen_a_b_c</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7446 With this facility, a package can pack several C submodules |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7447 into one single library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7448 with each submodule keeping its original open function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7449 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7450 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7451 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7452 All searchers except the first one (preload) return as the extra value |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7453 the file name where the module was found, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7454 as returned by <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7455 The first searcher returns no extra value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7456 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7457 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7458 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7459 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7460 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7461 <hr><h3><a name="pdf-package.searchpath"><code>package.searchpath (name, path [, sep [, rep]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7462 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7463 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7464 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7465 Searches for the given <code>name</code> in the given <code>path</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7466 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7467 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7468 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7469 A path is a string containing a sequence of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7470 <em>templates</em> separated by semicolons. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7471 For each template, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7472 the function replaces each interrogation mark (if any) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7473 in the template with a copy of <code>name</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7474 wherein all occurrences of <code>sep</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7475 (a dot, by default) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7476 were replaced by <code>rep</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7477 (the system's directory separator, by default), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7478 and then tries to open the resulting file name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7479 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7480 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7481 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7482 For instance, if the path is the string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7484 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7485 "./?.lua;./?.lc;/usr/local/?/init.lua" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7486 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7487 the search for the name <code>foo.a</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7488 will try to open the files |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7489 <code>./foo/a.lua</code>, <code>./foo/a.lc</code>, and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7490 <code>/usr/local/foo/a/init.lua</code>, in that order. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7491 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7492 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7493 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7494 Returns the resulting name of the first file that it can |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7495 open in read mode (after closing the file), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7496 or <b>nil</b> plus an error message if none succeeds. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7497 (This error message lists all file names it tried to open.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7498 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7499 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7500 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7501 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7502 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7503 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7504 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7505 <h2>6.4 – <a name="6.4">String Manipulation</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7506 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7507 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7508 This library provides generic functions for string manipulation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7509 such as finding and extracting substrings, and pattern matching. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7510 When indexing a string in Lua, the first character is at position 1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7511 (not at 0, as in C). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7512 Indices are allowed to be negative and are interpreted as indexing backwards, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7513 from the end of the string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7514 Thus, the last character is at position -1, and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7515 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7516 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7517 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7518 The string library provides all its functions inside the table |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7519 <a name="pdf-string"><code>string</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7520 It also sets a metatable for strings |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7521 where the <code>__index</code> field points to the <code>string</code> table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7522 Therefore, you can use the string functions in object-oriented style. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7523 For instance, <code>string.byte(s,i)</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7524 can be written as <code>s:byte(i)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7526 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7527 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7528 The string library assumes one-byte character encodings. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7529 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7530 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7531 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7532 <hr><h3><a name="pdf-string.byte"><code>string.byte (s [, i [, j]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7533 Returns the internal numerical codes of the characters <code>s[i]</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7534 <code>s[i+1]</code>, ..., <code>s[j]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7535 The default value for <code>i</code> is 1; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7536 the default value for <code>j</code> is <code>i</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7537 These indices are corrected |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7538 following the same rules of function <a href="#pdf-string.sub"><code>string.sub</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7540 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7541 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7542 Numerical codes are not necessarily portable across platforms. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7543 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7544 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7545 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7546 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7547 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7548 <hr><h3><a name="pdf-string.char"><code>string.char (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7549 Receives zero or more integers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7550 Returns a string with length equal to the number of arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7551 in which each character has the internal numerical code equal |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7552 to its corresponding argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7553 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7554 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7555 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7556 Numerical codes are not necessarily portable across platforms. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7557 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7558 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7559 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7561 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7562 <hr><h3><a name="pdf-string.dump"><code>string.dump (function [, strip])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7563 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7564 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7565 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7566 Returns a string containing a binary representation |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7567 (a <em>binary chunk</em>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7568 of the given function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7569 so that a later <a href="#pdf-load"><code>load</code></a> on this string returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7570 a copy of the function (but with new upvalues). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7571 If <code>strip</code> is a true value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7572 the binary representation is created without debug information |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7573 about the function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7574 (local variable names, lines, etc.). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7575 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7576 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7577 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7578 Functions with upvalues have only their number of upvalues saved. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7579 When (re)loaded, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7580 those upvalues receive fresh instances containing <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7581 (You can use the debug library to serialize |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7582 and reload the upvalues of a function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7583 in a way adequate to your needs.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7584 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7585 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7586 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7587 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7588 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7589 <hr><h3><a name="pdf-string.find"><code>string.find (s, pattern [, init [, plain]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7590 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7591 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7592 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7593 Looks for the first match of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7594 <code>pattern</code> (see <a href="#6.4.1">§6.4.1</a>) in the string <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7595 If it finds a match, then <code>find</code> returns the indices of <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7596 where this occurrence starts and ends; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7597 otherwise, it returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7598 A third, optional numerical argument <code>init</code> specifies |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7599 where to start the search; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7600 its default value is 1 and can be negative. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7601 A value of <b>true</b> as a fourth, optional argument <code>plain</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7602 turns off the pattern matching facilities, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7603 so the function does a plain "find substring" operation, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7604 with no characters in <code>pattern</code> being considered magic. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7605 Note that if <code>plain</code> is given, then <code>init</code> must be given as well. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7607 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7608 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7609 If the pattern has captures, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7610 then in a successful match |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7611 the captured values are also returned, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7612 after the two indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7614 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7615 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7616 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7617 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7618 <hr><h3><a name="pdf-string.format"><code>string.format (formatstring, ···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7619 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7620 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7621 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7622 Returns a formatted version of its variable number of arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7623 following the description given in its first argument (which must be a string). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7624 The format string follows the same rules as the ISO C function <code>sprintf</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7625 The only differences are that the options/modifiers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7626 <code>*</code>, <code>h</code>, <code>L</code>, <code>l</code>, <code>n</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7627 and <code>p</code> are not supported |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7628 and that there is an extra option, <code>q</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7629 The <code>q</code> option formats a string between double quotes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7630 using escape sequences when necessary to ensure that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7631 it can safely be read back by the Lua interpreter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7632 For instance, the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7633 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7634 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7635 string.format('%q', 'a string with "quotes" and \n new line') |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7636 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7637 may produce the string: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7638 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7639 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7640 "a string with \"quotes\" and \ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7641 new line" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7642 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7643 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7644 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7645 Options |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7646 <code>A</code> and <code>a</code> (when available), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7647 <code>E</code>, <code>e</code>, <code>f</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7648 <code>G</code>, and <code>g</code> all expect a number as argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7649 Options <code>c</code>, <code>d</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7650 <code>i</code>, <code>o</code>, <code>u</code>, <code>X</code>, and <code>x</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7651 expect an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7652 Option <code>q</code> expects a string; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7653 option <code>s</code> expects a string without embedded zeros. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7654 If the argument to option <code>s</code> is not a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7655 it is converted to one following the same rules of <a href="#pdf-tostring"><code>tostring</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7656 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7657 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7658 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7659 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7660 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7661 <hr><h3><a name="pdf-string.gmatch"><code>string.gmatch (s, pattern)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7662 Returns an iterator function that, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7663 each time it is called, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7664 returns the next captures from <code>pattern</code> (see <a href="#6.4.1">§6.4.1</a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7665 over the string <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7666 If <code>pattern</code> specifies no captures, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7667 then the whole match is produced in each call. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7668 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7669 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7670 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7671 As an example, the following loop |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7672 will iterate over all the words from string <code>s</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7673 printing one per line: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7674 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7675 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7676 s = "hello world from Lua" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7677 for w in string.gmatch(s, "%a+") do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7678 print(w) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7679 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7680 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7681 The next example collects all pairs <code>key=value</code> from the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7682 given string into a table: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7683 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7684 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7685 t = {} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7686 s = "from=world, to=Lua" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7687 for k, v in string.gmatch(s, "(%w+)=(%w+)") do |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7688 t[k] = v |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7689 end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7690 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7691 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7692 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7693 For this function, a caret '<code>^</code>' at the start of a pattern does not |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7694 work as an anchor, as this would prevent the iteration. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7696 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7697 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7698 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7699 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7700 <hr><h3><a name="pdf-string.gsub"><code>string.gsub (s, pattern, repl [, n])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7701 Returns a copy of <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7702 in which all (or the first <code>n</code>, if given) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7703 occurrences of the <code>pattern</code> (see <a href="#6.4.1">§6.4.1</a>) have been |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7704 replaced by a replacement string specified by <code>repl</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7705 which can be a string, a table, or a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7706 <code>gsub</code> also returns, as its second value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7707 the total number of matches that occurred. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7708 The name <code>gsub</code> comes from <em>Global SUBstitution</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7709 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7710 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7711 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7712 If <code>repl</code> is a string, then its value is used for replacement. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7713 The character <code>%</code> works as an escape character: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7714 any sequence in <code>repl</code> of the form <code>%<em>d</em></code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7715 with <em>d</em> between 1 and 9, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7716 stands for the value of the <em>d</em>-th captured substring. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7717 The sequence <code>%0</code> stands for the whole match. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7718 The sequence <code>%%</code> stands for a single <code>%</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7719 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7720 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7721 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7722 If <code>repl</code> is a table, then the table is queried for every match, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7723 using the first capture as the key. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7726 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7727 If <code>repl</code> is a function, then this function is called every time a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7728 match occurs, with all captured substrings passed as arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7729 in order. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7730 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7731 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7732 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7733 In any case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7734 if the pattern specifies no captures, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7735 then it behaves as if the whole pattern was inside a capture. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7736 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7738 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7739 If the value returned by the table query or by the function call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7740 is a string or a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7741 then it is used as the replacement string; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7742 otherwise, if it is <b>false</b> or <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7743 then there is no replacement |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7744 (that is, the original match is kept in the string). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7745 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7746 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7747 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7748 Here are some examples: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7749 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7750 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7751 x = string.gsub("hello world", "(%w+)", "%1 %1") |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7752 --> x="hello hello world world" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7754 x = string.gsub("hello world", "%w+", "%0 %0", 1) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7755 --> x="hello hello world" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7756 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7757 x = string.gsub("hello world from Lua", "(%w+)%s*(%w+)", "%2 %1") |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7758 --> x="world hello Lua from" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7759 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7760 x = string.gsub("home = $HOME, user = $USER", "%$(%w+)", os.getenv) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7761 --> x="home = /home/roberto, user = roberto" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7762 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7763 x = string.gsub("4+5 = $return 4+5$", "%$(.-)%$", function (s) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7764 return load(s)() |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7765 end) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7766 --> x="4+5 = 9" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7767 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7768 local t = {name="lua", version="5.3"} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7769 x = string.gsub("$name-$version.tar.gz", "%$(%w+)", t) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7770 --> x="lua-5.3.tar.gz" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7771 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7772 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7773 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7774 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7775 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7776 <hr><h3><a name="pdf-string.len"><code>string.len (s)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7777 Receives a string and returns its length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7778 The empty string <code>""</code> has length 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7779 Embedded zeros are counted, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7780 so <code>"a\000bc\000"</code> has length 5. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7781 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7782 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7783 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7784 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7785 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7786 <hr><h3><a name="pdf-string.lower"><code>string.lower (s)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7787 Receives a string and returns a copy of this string with all |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7788 uppercase letters changed to lowercase. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7789 All other characters are left unchanged. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7790 The definition of what an uppercase letter is depends on the current locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7792 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7793 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7794 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7795 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7796 <hr><h3><a name="pdf-string.match"><code>string.match (s, pattern [, init])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7797 Looks for the first <em>match</em> of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7798 <code>pattern</code> (see <a href="#6.4.1">§6.4.1</a>) in the string <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7799 If it finds one, then <code>match</code> returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7800 the captures from the pattern; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7801 otherwise it returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7802 If <code>pattern</code> specifies no captures, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7803 then the whole match is returned. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7804 A third, optional numerical argument <code>init</code> specifies |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7805 where to start the search; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7806 its default value is 1 and can be negative. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7807 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7808 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7810 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7811 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7812 <hr><h3><a name="pdf-string.pack"><code>string.pack (fmt, v1, v2, ···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7813 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7814 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7815 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7816 Returns a binary string containing the values <code>v1</code>, <code>v2</code>, etc. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7817 packed (that is, serialized in binary form) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7818 according to the format string <code>fmt</code> (see <a href="#6.4.2">§6.4.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7819 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7822 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7823 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7824 <hr><h3><a name="pdf-string.packsize"><code>string.packsize (fmt)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7825 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7826 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7827 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7828 Returns the size of a string resulting from <a href="#pdf-string.pack"><code>string.pack</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7829 with the given format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7830 The format string cannot have the variable-length options |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7831 '<code>s</code>' or '<code>z</code>' (see <a href="#6.4.2">§6.4.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7833 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7834 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7835 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7836 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7837 <hr><h3><a name="pdf-string.rep"><code>string.rep (s, n [, sep])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7838 Returns a string that is the concatenation of <code>n</code> copies of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7839 the string <code>s</code> separated by the string <code>sep</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7840 The default value for <code>sep</code> is the empty string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7841 (that is, no separator). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7842 Returns the empty string if <code>n</code> is not positive. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7843 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7844 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7845 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7846 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7847 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7848 <hr><h3><a name="pdf-string.reverse"><code>string.reverse (s)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7849 Returns a string that is the string <code>s</code> reversed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7850 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7851 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7852 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7853 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7854 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7855 <hr><h3><a name="pdf-string.sub"><code>string.sub (s, i [, j])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7856 Returns the substring of <code>s</code> that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7857 starts at <code>i</code> and continues until <code>j</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7858 <code>i</code> and <code>j</code> can be negative. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7859 If <code>j</code> is absent, then it is assumed to be equal to -1 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7860 (which is the same as the string length). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7861 In particular, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7862 the call <code>string.sub(s,1,j)</code> returns a prefix of <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7863 with length <code>j</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7864 and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7865 with length <code>i</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7867 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7868 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7869 If, after the translation of negative indices, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7870 <code>i</code> is less than 1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7871 it is corrected to 1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7872 If <code>j</code> is greater than the string length, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7873 it is corrected to that length. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7874 If, after these corrections, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7875 <code>i</code> is greater than <code>j</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7876 the function returns the empty string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7877 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7878 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7879 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7880 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7881 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7882 <hr><h3><a name="pdf-string.unpack"><code>string.unpack (fmt, s [, pos])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7883 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7884 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7885 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7886 Returns the values packed in string <code>s</code> (see <a href="#pdf-string.pack"><code>string.pack</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7887 according to the format string <code>fmt</code> (see <a href="#6.4.2">§6.4.2</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7888 An optional <code>pos</code> marks where |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7889 to start reading in <code>s</code> (default is 1). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7890 After the read values, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7891 this function also returns the index of the first unread byte in <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7892 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7893 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7894 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7895 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7896 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7897 <hr><h3><a name="pdf-string.upper"><code>string.upper (s)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7898 Receives a string and returns a copy of this string with all |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7899 lowercase letters changed to uppercase. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7900 All other characters are left unchanged. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7901 The definition of what a lowercase letter is depends on the current locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7902 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7903 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7904 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7905 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7906 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7907 <h3>6.4.1 – <a name="6.4.1">Patterns</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7908 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7909 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7910 Patterns in Lua are described by regular strings, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7911 which are interpreted as patterns by the pattern-matching functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7912 <a href="#pdf-string.find"><code>string.find</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7913 <a href="#pdf-string.gmatch"><code>string.gmatch</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7914 <a href="#pdf-string.gsub"><code>string.gsub</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7915 and <a href="#pdf-string.match"><code>string.match</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7916 This section describes the syntax and the meaning |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7917 (that is, what they match) of these strings. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7918 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7919 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7920 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7921 <h4>Character Class:</h4><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7922 A <em>character class</em> is used to represent a set of characters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7923 The following combinations are allowed in describing a character class: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7924 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7925 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7926 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7927 <li><b><em>x</em>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7928 (where <em>x</em> is not one of the <em>magic characters</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7929 <code>^$()%.[]*+-?</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7930 represents the character <em>x</em> itself. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7931 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7933 <li><b><code>.</code>: </b> (a dot) represents all characters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7934 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7935 <li><b><code>%a</code>: </b> represents all letters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7937 <li><b><code>%c</code>: </b> represents all control characters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7938 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7939 <li><b><code>%d</code>: </b> represents all digits.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7941 <li><b><code>%g</code>: </b> represents all printable characters except space.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7942 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7943 <li><b><code>%l</code>: </b> represents all lowercase letters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7944 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7945 <li><b><code>%p</code>: </b> represents all punctuation characters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7946 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7947 <li><b><code>%s</code>: </b> represents all space characters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7948 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7949 <li><b><code>%u</code>: </b> represents all uppercase letters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7950 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7951 <li><b><code>%w</code>: </b> represents all alphanumeric characters.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7952 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7953 <li><b><code>%x</code>: </b> represents all hexadecimal digits.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7954 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7955 <li><b><code>%<em>x</em></code>: </b> (where <em>x</em> is any non-alphanumeric character) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7956 represents the character <em>x</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7957 This is the standard way to escape the magic characters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7958 Any non-alphanumeric character |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7959 (including all punctuations, even the non-magical) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7960 can be preceded by a '<code>%</code>' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7961 when used to represent itself in a pattern. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7962 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7964 <li><b><code>[<em>set</em>]</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7965 represents the class which is the union of all |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7966 characters in <em>set</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7967 A range of characters can be specified by |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7968 separating the end characters of the range, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7969 in ascending order, with a '<code>-</code>'. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7970 All classes <code>%</code><em>x</em> described above can also be used as |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7971 components in <em>set</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7972 All other characters in <em>set</em> represent themselves. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7973 For example, <code>[%w_]</code> (or <code>[_%w]</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7974 represents all alphanumeric characters plus the underscore, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7975 <code>[0-7]</code> represents the octal digits, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7976 and <code>[0-7%l%-]</code> represents the octal digits plus |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7977 the lowercase letters plus the '<code>-</code>' character. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7978 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7979 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7980 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7981 The interaction between ranges and classes is not defined. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7982 Therefore, patterns like <code>[%a-z]</code> or <code>[a-%%]</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7983 have no meaning. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7984 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7985 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7986 <li><b><code>[^<em>set</em>]</code>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7987 represents the complement of <em>set</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7988 where <em>set</em> is interpreted as above. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7989 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7990 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7991 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7992 For all classes represented by single letters (<code>%a</code>, <code>%c</code>, etc.), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7993 the corresponding uppercase letter represents the complement of the class. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7994 For instance, <code>%S</code> represents all non-space characters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7995 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7996 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7997 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7998 The definitions of letter, space, and other character groups |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
7999 depend on the current locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8000 In particular, the class <code>[a-z]</code> may not be equivalent to <code>%l</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8001 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8002 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8003 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8006 <h4>Pattern Item:</h4><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8007 A <em>pattern item</em> can be |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8008 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8009 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8010 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8011 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8012 a single character class, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8013 which matches any single character in the class; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8014 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8015 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8016 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8017 a single character class followed by '<code>*</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8018 which matches zero or more repetitions of characters in the class. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8019 These repetition items will always match the longest possible sequence; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8020 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8021 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8022 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8023 a single character class followed by '<code>+</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8024 which matches one or more repetitions of characters in the class. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8025 These repetition items will always match the longest possible sequence; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8026 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8027 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8028 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8029 a single character class followed by '<code>-</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8030 which also matches zero or more repetitions of characters in the class. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8031 Unlike '<code>*</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8032 these repetition items will always match the shortest possible sequence; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8033 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8034 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8035 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8036 a single character class followed by '<code>?</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8037 which matches zero or one occurrence of a character in the class. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8038 It always matches one occurrence if possible; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8039 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8040 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8041 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8042 <code>%<em>n</em></code>, for <em>n</em> between 1 and 9; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8043 such item matches a substring equal to the <em>n</em>-th captured string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8044 (see below); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8045 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8046 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8047 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8048 <code>%b<em>xy</em></code>, where <em>x</em> and <em>y</em> are two distinct characters; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8049 such item matches strings that start with <em>x</em>, end with <em>y</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8050 and where the <em>x</em> and <em>y</em> are <em>balanced</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8051 This means that, if one reads the string from left to right, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8052 counting <em>+1</em> for an <em>x</em> and <em>-1</em> for a <em>y</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8053 the ending <em>y</em> is the first <em>y</em> where the count reaches 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8054 For instance, the item <code>%b()</code> matches expressions with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8055 balanced parentheses. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8056 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8057 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8058 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8059 <code>%f[<em>set</em>]</code>, a <em>frontier pattern</em>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8060 such item matches an empty string at any position such that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8061 the next character belongs to <em>set</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8062 and the previous character does not belong to <em>set</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8063 The set <em>set</em> is interpreted as previously described. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8064 The beginning and the end of the subject are handled as if |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8065 they were the character '<code>\0</code>'. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8066 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8067 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8068 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8069 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8070 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8072 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8073 <h4>Pattern:</h4><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8074 A <em>pattern</em> is a sequence of pattern items. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8075 A caret '<code>^</code>' at the beginning of a pattern anchors the match at the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8076 beginning of the subject string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8077 A '<code>$</code>' at the end of a pattern anchors the match at the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8078 end of the subject string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8079 At other positions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8080 '<code>^</code>' and '<code>$</code>' have no special meaning and represent themselves. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8081 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8083 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8084 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8085 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8086 <h4>Captures:</h4><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8087 A pattern can contain sub-patterns enclosed in parentheses; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8088 they describe <em>captures</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8089 When a match succeeds, the substrings of the subject string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8090 that match captures are stored (<em>captured</em>) for future use. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8091 Captures are numbered according to their left parentheses. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8092 For instance, in the pattern <code>"(a*(.)%w(%s*))"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8093 the part of the string matching <code>"a*(.)%w(%s*)"</code> is |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8094 stored as the first capture (and therefore has number 1); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8095 the character matching "<code>.</code>" is captured with number 2, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8096 and the part matching "<code>%s*</code>" has number 3. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8097 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8099 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8100 As a special case, the empty capture <code>()</code> captures |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8101 the current string position (a number). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8102 For instance, if we apply the pattern <code>"()aa()"</code> on the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8103 string <code>"flaaap"</code>, there will be two captures: 3 and 5. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8104 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8105 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8106 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8109 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8110 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8111 <h3>6.4.2 – <a name="6.4.2">Format Strings for Pack and Unpack</a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8112 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8113 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8114 The first argument to <a href="#pdf-string.pack"><code>string.pack</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8115 <a href="#pdf-string.packsize"><code>string.packsize</code></a>, and <a href="#pdf-string.unpack"><code>string.unpack</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8116 is a format string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8117 which describes the layout of the structure being created or read. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8118 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8119 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8120 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8121 A format string is a sequence of conversion options. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8122 The conversion options are as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8123 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8124 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8125 <li><b><code><</code>: </b>sets little endian</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8126 <li><b><code>></code>: </b>sets big endian</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8127 <li><b><code>=</code>: </b>sets native endian</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8128 <li><b><code>![<em>n</em>]</code>: </b>sets maximum alignment to <code>n</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8129 (default is native alignment)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8130 <li><b><code>b</code>: </b>a signed byte (<code>char</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8131 <li><b><code>B</code>: </b>an unsigned byte (<code>char</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8132 <li><b><code>h</code>: </b>a signed <code>short</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8133 <li><b><code>H</code>: </b>an unsigned <code>short</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8134 <li><b><code>l</code>: </b>a signed <code>long</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8135 <li><b><code>L</code>: </b>an unsigned <code>long</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8136 <li><b><code>j</code>: </b>a <code>lua_Integer</code></li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8137 <li><b><code>J</code>: </b>a <code>lua_Unsigned</code></li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8138 <li><b><code>T</code>: </b>a <code>size_t</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8139 <li><b><code>i[<em>n</em>]</code>: </b>a signed <code>int</code> with <code>n</code> bytes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8140 (default is native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8141 <li><b><code>I[<em>n</em>]</code>: </b>an unsigned <code>int</code> with <code>n</code> bytes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8142 (default is native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8143 <li><b><code>f</code>: </b>a <code>float</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8144 <li><b><code>d</code>: </b>a <code>double</code> (native size)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8145 <li><b><code>n</code>: </b>a <code>lua_Number</code></li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8146 <li><b><code>c<em>n</em></code>: </b>a fixed-sized string with <code>n</code> bytes</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8147 <li><b><code>z</code>: </b>a zero-terminated string</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8148 <li><b><code>s[<em>n</em>]</code>: </b>a string preceded by its length |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8149 coded as an unsigned integer with <code>n</code> bytes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8150 (default is a <code>size_t</code>)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8151 <li><b><code>x</code>: </b>one byte of padding</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8152 <li><b><code>X<em>op</em></code>: </b>an empty item that aligns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8153 according to option <code>op</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8154 (which is otherwise ignored)</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8155 <li><b>'<code> </code>': </b>(empty space) ignored</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8156 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8157 (A "<code>[<em>n</em>]</code>" means an optional integral numeral.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8158 Except for padding, spaces, and configurations |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8159 (options "<code>xX <=>!</code>"), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8160 each option corresponds to an argument (in <a href="#pdf-string.pack"><code>string.pack</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8161 or a result (in <a href="#pdf-string.unpack"><code>string.unpack</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8162 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8163 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8164 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8165 For options "<code>!<em>n</em></code>", "<code>s<em>n</em></code>", "<code>i<em>n</em></code>", and "<code>I<em>n</em></code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8166 <code>n</code> can be any integer between 1 and 16. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8167 All integral options check overflows; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8168 <a href="#pdf-string.pack"><code>string.pack</code></a> checks whether the given value fits in the given size; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8169 <a href="#pdf-string.unpack"><code>string.unpack</code></a> checks whether the read value fits in a Lua integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8170 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8171 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8172 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8173 Any format string starts as if prefixed by "<code>!1=</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8174 that is, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8175 with maximum alignment of 1 (no alignment) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8176 and native endianness. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8177 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8178 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8179 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8180 Alignment works as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8181 For each option, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8182 the format gets extra padding until the data starts |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8183 at an offset that is a multiple of the minimum between the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8184 option size and the maximum alignment; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8185 this minimum must be a power of 2. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8186 Options "<code>c</code>" and "<code>z</code>" are not aligned; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8187 option "<code>s</code>" follows the alignment of its starting integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8188 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8189 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8190 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8191 All padding is filled with zeros by <a href="#pdf-string.pack"><code>string.pack</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8192 (and ignored by <a href="#pdf-string.unpack"><code>string.unpack</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8193 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8194 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8195 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8196 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8198 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8199 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8200 <h2>6.5 – <a name="6.5">UTF-8 Support</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8202 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8203 This library provides basic support for UTF-8 encoding. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8204 It provides all its functions inside the table <a name="pdf-utf8"><code>utf8</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8205 This library does not provide any support for Unicode other |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8206 than the handling of the encoding. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8207 Any operation that needs the meaning of a character, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8208 such as character classification, is outside its scope. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8210 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8211 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8212 Unless stated otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8213 all functions that expect a byte position as a parameter |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8214 assume that the given position is either the start of a byte sequence |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8215 or one plus the length of the subject string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8216 As in the string library, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8217 negative indices count from the end of the string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8218 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8219 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8220 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8221 <hr><h3><a name="pdf-utf8.char"><code>utf8.char (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8222 Receives zero or more integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8223 converts each one to its corresponding UTF-8 byte sequence |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8224 and returns a string with the concatenation of all these sequences. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8225 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8226 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8227 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8228 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8229 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8230 <hr><h3><a name="pdf-utf8.charpattern"><code>utf8.charpattern</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8231 The pattern (a string, not a function) "<code>[\0-\x7F\xC2-\xF4][\x80-\xBF]*</code>" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8232 (see <a href="#6.4.1">§6.4.1</a>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8233 which matches exactly one UTF-8 byte sequence, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8234 assuming that the subject is a valid UTF-8 string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8237 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8238 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8239 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8240 <hr><h3><a name="pdf-utf8.codes"><code>utf8.codes (s)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8243 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8244 Returns values so that the construction |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8245 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8246 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8247 for p, c in utf8.codes(s) do <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8248 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8249 will iterate over all characters in string <code>s</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8250 with <code>p</code> being the position (in bytes) and <code>c</code> the code point |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8251 of each character. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8252 It raises an error if it meets any invalid byte sequence. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8253 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8255 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8256 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8257 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8258 <hr><h3><a name="pdf-utf8.codepoint"><code>utf8.codepoint (s [, i [, j]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8259 Returns the codepoints (as integers) from all characters in <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8260 that start between byte position <code>i</code> and <code>j</code> (both included). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8261 The default for <code>i</code> is 1 and for <code>j</code> is <code>i</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8262 It raises an error if it meets any invalid byte sequence. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8263 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8264 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8265 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8266 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8267 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8268 <hr><h3><a name="pdf-utf8.len"><code>utf8.len (s [, i [, j]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8269 Returns the number of UTF-8 characters in string <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8270 that start between positions <code>i</code> and <code>j</code> (both inclusive). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8271 The default for <code>i</code> is 1 and for <code>j</code> is -1. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8272 If it finds any invalid byte sequence, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8273 returns a false value plus the position of the first invalid byte. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8275 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8276 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8277 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8278 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8279 <hr><h3><a name="pdf-utf8.offset"><code>utf8.offset (s, n [, i])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8280 Returns the position (in bytes) where the encoding of the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8281 <code>n</code>-th character of <code>s</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8282 (counting from position <code>i</code>) starts. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8283 A negative <code>n</code> gets characters before position <code>i</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8284 The default for <code>i</code> is 1 when <code>n</code> is non-negative |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8285 and <code>#s + 1</code> otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8286 so that <code>utf8.offset(s, -n)</code> gets the offset of the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8287 <code>n</code>-th character from the end of the string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8288 If the specified character is neither in the subject |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8289 nor right after its end, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8290 the function returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8291 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8292 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8293 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8294 As a special case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8295 when <code>n</code> is 0 the function returns the start of the encoding |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8296 of the character that contains the <code>i</code>-th byte of <code>s</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8297 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8298 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8299 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8300 This function assumes that <code>s</code> is a valid UTF-8 string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8301 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8302 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8303 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8304 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8305 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8306 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8307 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8308 <h2>6.6 – <a name="6.6">Table Manipulation</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8309 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8310 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8311 This library provides generic functions for table manipulation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8312 It provides all its functions inside the table <a name="pdf-table"><code>table</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8313 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8314 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8315 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8316 Remember that, whenever an operation needs the length of a table, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8317 the table must be a proper sequence |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8318 or have a <code>__len</code> metamethod (see <a href="#3.4.7">§3.4.7</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8319 All functions ignore non-numeric keys |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8320 in the tables given as arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8321 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8322 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8323 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8324 <hr><h3><a name="pdf-table.concat"><code>table.concat (list [, sep [, i [, j]]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8325 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8326 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8327 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8328 Given a list where all elements are strings or numbers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8329 returns the string <code>list[i]..sep..list[i+1] ··· sep..list[j]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8330 The default value for <code>sep</code> is the empty string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8331 the default for <code>i</code> is 1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8332 and the default for <code>j</code> is <code>#list</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8333 If <code>i</code> is greater than <code>j</code>, returns the empty string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8334 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8335 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8336 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8337 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8338 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8339 <hr><h3><a name="pdf-table.insert"><code>table.insert (list, [pos,] value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8340 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8341 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8342 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8343 Inserts element <code>value</code> at position <code>pos</code> in <code>list</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8344 shifting up the elements |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8345 <code>list[pos], list[pos+1], ···, list[#list]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8346 The default value for <code>pos</code> is <code>#list+1</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8347 so that a call <code>table.insert(t,x)</code> inserts <code>x</code> at the end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8348 of list <code>t</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8351 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8352 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8353 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8354 <hr><h3><a name="pdf-table.move"><code>table.move (a1, f, e, t [,a2])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8355 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8357 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8358 Moves elements from table <code>a1</code> to table <code>a2</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8359 This function performs the equivalent to the following |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8360 multiple assignment: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8361 <code>a2[t],··· = a1[f],···,a1[e]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8362 The default for <code>a2</code> is <code>a1</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8363 The destination range can overlap with the source range. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8364 Index <code>f</code> must be positive. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8365 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8366 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8367 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8368 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8369 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8370 <hr><h3><a name="pdf-table.pack"><code>table.pack (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8371 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8372 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8373 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8374 Returns a new table with all parameters stored into keys 1, 2, etc. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8375 and with a field "<code>n</code>" with the total number of parameters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8376 Note that the resulting table may not be a sequence. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8377 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8378 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8379 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8380 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8381 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8382 <hr><h3><a name="pdf-table.remove"><code>table.remove (list [, pos])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8383 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8384 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8385 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8386 Removes from <code>list</code> the element at position <code>pos</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8387 returning the value of the removed element. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8388 When <code>pos</code> is an integer between 1 and <code>#list</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8389 it shifts down the elements |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8390 <code>list[pos+1], list[pos+2], ···, list[#list]</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8391 and erases element <code>list[#list]</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8392 The index <code>pos</code> can also be 0 when <code>#list</code> is 0, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8393 or <code>#list + 1</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8394 in those cases, the function erases the element <code>list[pos]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8395 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8396 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8397 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8398 The default value for <code>pos</code> is <code>#list</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8399 so that a call <code>table.remove(l)</code> removes the last element |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8400 of list <code>l</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8401 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8403 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8404 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8405 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8406 <hr><h3><a name="pdf-table.sort"><code>table.sort (list [, comp])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8407 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8408 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8409 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8410 Sorts list elements in a given order, <em>in-place</em>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8411 from <code>list[1]</code> to <code>list[#list]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8412 If <code>comp</code> is given, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8413 then it must be a function that receives two list elements |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8414 and returns true when the first element must come |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8415 before the second in the final order |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8416 (so that <code>not comp(list[i+1],list[i])</code> will be true after the sort). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8417 If <code>comp</code> is not given, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8418 then the standard Lua operator <code><</code> is used instead. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8419 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8420 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8421 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8422 The sort algorithm is not stable; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8423 that is, elements considered equal by the given order |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8424 may have their relative positions changed by the sort. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8425 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8426 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8427 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8428 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8429 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8430 <hr><h3><a name="pdf-table.unpack"><code>table.unpack (list [, i [, j]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8431 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8432 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8433 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8434 Returns the elements from the given list. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8435 This function is equivalent to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8436 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8437 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8438 return list[i], list[i+1], ···, list[j] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8439 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8440 By default, <code>i</code> is 1 and <code>j</code> is <code>#list</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8441 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8442 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8443 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8444 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8445 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8446 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8448 <h2>6.7 – <a name="6.7">Mathematical Functions</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8449 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8450 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8451 This library provides basic mathematical functions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8452 It provides all its functions and constants inside the table <a name="pdf-math"><code>math</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8453 Functions with the annotation "<code>integer/float</code>" give |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8454 integer results for integer arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8455 and float results for float (or mixed) arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8456 Rounding functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8457 (<a href="#pdf-math.ceil"><code>math.ceil</code></a>, <a href="#pdf-math.floor"><code>math.floor</code></a>, and <a href="#pdf-math.modf"><code>math.modf</code></a>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8458 return an integer when the result fits in the range of an integer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8459 or a float otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8460 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8461 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8462 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8463 <hr><h3><a name="pdf-math.abs"><code>math.abs (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8464 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8465 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8466 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8467 Returns the absolute value of <code>x</code>. (integer/float) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8468 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8469 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8470 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8471 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8472 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8473 <hr><h3><a name="pdf-math.acos"><code>math.acos (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8474 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8475 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8476 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8477 Returns the arc cosine of <code>x</code> (in radians). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8478 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8479 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8480 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8481 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8482 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8483 <hr><h3><a name="pdf-math.asin"><code>math.asin (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8484 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8485 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8486 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8487 Returns the arc sine of <code>x</code> (in radians). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8488 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8489 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8490 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8491 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8492 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8493 <hr><h3><a name="pdf-math.atan"><code>math.atan (y [, x])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8494 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8495 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8496 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8497 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8498 Returns the arc tangent of <code>y/x</code> (in radians), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8499 but uses the signs of both parameters to find the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8500 quadrant of the result. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8501 (It also handles correctly the case of <code>x</code> being zero.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8502 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8503 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8504 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8505 The default value for <code>x</code> is 1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8506 so that the call <code>math.atan(y)</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8507 returns the arc tangent of <code>y</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8508 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8509 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8510 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8511 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8512 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8513 <hr><h3><a name="pdf-math.ceil"><code>math.ceil (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8514 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8515 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8516 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8517 Returns the smallest integral value larger than or equal to <code>x</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8518 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8519 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8520 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8521 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8522 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8523 <hr><h3><a name="pdf-math.cos"><code>math.cos (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8524 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8525 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8526 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8527 Returns the cosine of <code>x</code> (assumed to be in radians). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8528 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8529 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8530 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8531 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8532 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8533 <hr><h3><a name="pdf-math.deg"><code>math.deg (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8534 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8535 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8536 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8537 Converts the angle <code>x</code> from radians to degrees. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8538 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8539 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8540 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8541 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8542 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8543 <hr><h3><a name="pdf-math.exp"><code>math.exp (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8544 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8545 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8546 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8547 Returns the value <em>e<sup>x</sup></em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8548 (where <code>e</code> is the base of natural logarithms). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8549 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8550 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8551 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8552 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8553 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8554 <hr><h3><a name="pdf-math.floor"><code>math.floor (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8555 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8556 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8557 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8558 Returns the largest integral value smaller than or equal to <code>x</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8559 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8561 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8562 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8563 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8564 <hr><h3><a name="pdf-math.fmod"><code>math.fmod (x, y)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8566 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8567 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8568 Returns the remainder of the division of <code>x</code> by <code>y</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8569 that rounds the quotient towards zero. (integer/float) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8570 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8571 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8572 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8573 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8574 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8575 <hr><h3><a name="pdf-math.huge"><code>math.huge</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8576 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8577 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8578 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8579 The float value <code>HUGE_VAL</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8580 a value larger than any other numerical value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8581 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8582 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8583 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8584 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8585 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8586 <hr><h3><a name="pdf-math.log"><code>math.log (x [, base])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8587 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8588 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8589 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8590 Returns the logarithm of <code>x</code> in the given base. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8591 The default for <code>base</code> is <em>e</em> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8592 (so that the function returns the natural logarithm of <code>x</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8593 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8594 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8595 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8596 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8597 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8598 <hr><h3><a name="pdf-math.max"><code>math.max (x, ···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8599 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8600 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8601 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8602 Returns the argument with the maximum value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8603 according to the Lua operator <code><</code>. (integer/float) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8604 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8605 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8607 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8608 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8609 <hr><h3><a name="pdf-math.maxinteger"><code>math.maxinteger</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8610 An integer with the maximum value for an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8611 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8612 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8614 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8615 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8616 <hr><h3><a name="pdf-math.min"><code>math.min (x, ···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8617 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8618 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8619 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8620 Returns the argument with the minimum value, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8621 according to the Lua operator <code><</code>. (integer/float) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8622 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8623 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8624 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8625 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8626 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8627 <hr><h3><a name="pdf-math.mininteger"><code>math.mininteger</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8628 An integer with the minimum value for an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8629 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8630 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8631 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8632 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8633 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8634 <hr><h3><a name="pdf-math.modf"><code>math.modf (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8635 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8636 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8637 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8638 Returns the integral part of <code>x</code> and the fractional part of <code>x</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8639 Its second result is always a float. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8640 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8641 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8642 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8643 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8644 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8645 <hr><h3><a name="pdf-math.pi"><code>math.pi</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8648 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8649 The value of <em>π</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8650 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8651 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8652 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8653 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8654 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8655 <hr><h3><a name="pdf-math.rad"><code>math.rad (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8656 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8657 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8658 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8659 Converts the angle <code>x</code> from degrees to radians. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8660 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8661 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8662 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8663 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8664 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8665 <hr><h3><a name="pdf-math.random"><code>math.random ([m [, n]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8666 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8667 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8668 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8669 When called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8670 returns a pseudo-random float with uniform distribution |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8671 in the range <em>[0,1)</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8672 When called with two integers <code>m</code> and <code>n</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8673 <code>math.random</code> returns a pseudo-random integer |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8674 with uniform distribution in the range <em>[m, n]</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8675 (The value <em>m-n</em> cannot be negative and must fit in a Lua integer.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8676 The call <code>math.random(n)</code> is equivalent to <code>math.random(1,n)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8677 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8678 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8679 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8680 This function is an interface to the underling |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8681 pseudo-random generator function provided by C. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8682 No guarantees can be given for its statistical properties. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8683 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8684 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8685 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8686 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8687 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8688 <hr><h3><a name="pdf-math.randomseed"><code>math.randomseed (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8689 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8690 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8691 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8692 Sets <code>x</code> as the "seed" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8693 for the pseudo-random generator: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8694 equal seeds produce equal sequences of numbers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8696 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8697 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8698 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8699 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8700 <hr><h3><a name="pdf-math.sin"><code>math.sin (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8701 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8702 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8703 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8704 Returns the sine of <code>x</code> (assumed to be in radians). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8705 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8706 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8707 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8708 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8709 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8710 <hr><h3><a name="pdf-math.sqrt"><code>math.sqrt (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8711 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8712 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8713 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8714 Returns the square root of <code>x</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8715 (You can also use the expression <code>x^0.5</code> to compute this value.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8716 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8717 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8718 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8719 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8720 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8721 <hr><h3><a name="pdf-math.tan"><code>math.tan (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8722 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8723 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8724 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8725 Returns the tangent of <code>x</code> (assumed to be in radians). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8726 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8727 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8728 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8729 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8730 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8731 <hr><h3><a name="pdf-math.tointeger"><code>math.tointeger (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8732 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8733 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8734 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8735 If the value <code>x</code> is convertible to an integer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8736 returns that integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8737 Otherwise, returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8738 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8739 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8740 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8741 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8742 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8743 <hr><h3><a name="pdf-math.type"><code>math.type (x)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8744 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8745 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8746 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8747 Returns "<code>integer</code>" if <code>x</code> is an integer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8748 "<code>float</code>" if it is a float, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8749 or <b>nil</b> if <code>x</code> is not a number. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8750 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8751 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8752 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8754 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8755 <hr><h3><a name="pdf-math.ult"><code>math.ult (m, n)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8756 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8757 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8758 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8759 Returns a boolean, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8760 true if integer <code>m</code> is below integer <code>n</code> when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8761 they are compared as unsigned integers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8762 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8763 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8764 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8765 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8766 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8767 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8768 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8769 <h2>6.8 – <a name="6.8">Input and Output Facilities</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8770 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8771 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8772 The I/O library provides two different styles for file manipulation. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8773 The first one uses implicit file handles; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8774 that is, there are operations to set a default input file and a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8775 default output file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8776 and all input/output operations are over these default files. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8777 The second style uses explicit file handles. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8778 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8779 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8780 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8781 When using implicit file handles, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8782 all operations are supplied by table <a name="pdf-io"><code>io</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8783 When using explicit file handles, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8784 the operation <a href="#pdf-io.open"><code>io.open</code></a> returns a file handle |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8785 and then all operations are supplied as methods of the file handle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8786 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8787 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8788 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8789 The table <code>io</code> also provides |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8790 three predefined file handles with their usual meanings from C: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8791 <a name="pdf-io.stdin"><code>io.stdin</code></a>, <a name="pdf-io.stdout"><code>io.stdout</code></a>, and <a name="pdf-io.stderr"><code>io.stderr</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8792 The I/O library never closes these files. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8793 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8794 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8795 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8796 Unless otherwise stated, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8797 all I/O functions return <b>nil</b> on failure |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8798 (plus an error message as a second result and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8799 a system-dependent error code as a third result) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8800 and some value different from <b>nil</b> on success. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8801 On non-POSIX systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8802 the computation of the error message and error code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8803 in case of errors |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8804 may be not thread safe, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8805 because they rely on the global C variable <code>errno</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8807 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8808 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8809 <hr><h3><a name="pdf-io.close"><code>io.close ([file])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8810 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8811 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8812 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8813 Equivalent to <code>file:close()</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8814 Without a <code>file</code>, closes the default output file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8815 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8816 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8817 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8818 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8819 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8820 <hr><h3><a name="pdf-io.flush"><code>io.flush ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8821 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8822 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8823 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8824 Equivalent to <code>io.output():flush()</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8825 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8826 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8827 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8828 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8829 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8830 <hr><h3><a name="pdf-io.input"><code>io.input ([file])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8831 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8832 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8833 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8834 When called with a file name, it opens the named file (in text mode), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8835 and sets its handle as the default input file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8836 When called with a file handle, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8837 it simply sets this file handle as the default input file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8838 When called without parameters, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8839 it returns the current default input file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8840 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8841 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8842 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8843 In case of errors this function raises the error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8844 instead of returning an error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8845 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8846 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8847 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8848 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8849 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8850 <hr><h3><a name="pdf-io.lines"><code>io.lines ([filename ···])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8851 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8852 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8853 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8854 Opens the given file name in read mode |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8855 and returns an iterator function that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8856 works like <code>file:lines(···)</code> over the opened file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8857 When the iterator function detects the end of file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8858 it returns no values (to finish the loop) and automatically closes the file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8859 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8860 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8861 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8862 The call <code>io.lines()</code> (with no file name) is equivalent |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8863 to <code>io.input():lines("*l")</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8864 that is, it iterates over the lines of the default input file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8865 In this case it does not close the file when the loop ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8866 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8867 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8868 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8869 In case of errors this function raises the error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8870 instead of returning an error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8871 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8872 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8873 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8874 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8875 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8876 <hr><h3><a name="pdf-io.open"><code>io.open (filename [, mode])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8877 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8878 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8879 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8880 This function opens a file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8881 in the mode specified in the string <code>mode</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8882 It returns a new file handle, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8883 or, in case of errors, <b>nil</b> plus an error message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8884 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8885 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8886 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8887 The <code>mode</code> string can be any of the following: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8888 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8889 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8890 <li><b>"<code>r</code>": </b> read mode (the default);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8891 <li><b>"<code>w</code>": </b> write mode;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8892 <li><b>"<code>a</code>": </b> append mode;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8893 <li><b>"<code>r+</code>": </b> update mode, all previous data is preserved;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8894 <li><b>"<code>w+</code>": </b> update mode, all previous data is erased;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8895 <li><b>"<code>a+</code>": </b> append update mode, previous data is preserved, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8896 writing is only allowed at the end of file.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8897 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8898 The <code>mode</code> string can also have a '<code>b</code>' at the end, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8899 which is needed in some systems to open the file in binary mode. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8900 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8901 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8902 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8903 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8904 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8905 <hr><h3><a name="pdf-io.output"><code>io.output ([file])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8906 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8907 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8908 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8909 Similar to <a href="#pdf-io.input"><code>io.input</code></a>, but operates over the default output file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8911 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8912 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8913 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8914 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8915 <hr><h3><a name="pdf-io.popen"><code>io.popen (prog [, mode])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8916 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8917 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8918 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8919 This function is system dependent and is not available |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8920 on all platforms. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8921 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8923 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8924 Starts program <code>prog</code> in a separated process and returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8925 a file handle that you can use to read data from this program |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8926 (if <code>mode</code> is <code>"r"</code>, the default) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8927 or to write data to this program |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8928 (if <code>mode</code> is <code>"w"</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8929 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8930 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8931 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8933 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8934 <hr><h3><a name="pdf-io.read"><code>io.read (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8935 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8936 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8937 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8938 Equivalent to <code>io.input():read(···)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8939 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8941 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8942 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8943 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8944 <hr><h3><a name="pdf-io.tmpfile"><code>io.tmpfile ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8945 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8946 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8947 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8948 Returns a handle for a temporary file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8949 This file is opened in update mode |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8950 and it is automatically removed when the program ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8951 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8952 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8953 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8954 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8955 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8956 <hr><h3><a name="pdf-io.type"><code>io.type (obj)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8957 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8958 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8959 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8960 Checks whether <code>obj</code> is a valid file handle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8961 Returns the string <code>"file"</code> if <code>obj</code> is an open file handle, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8962 <code>"closed file"</code> if <code>obj</code> is a closed file handle, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8963 or <b>nil</b> if <code>obj</code> is not a file handle. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8964 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8965 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8966 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8967 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8968 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8969 <hr><h3><a name="pdf-io.write"><code>io.write (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8970 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8971 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8972 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8973 Equivalent to <code>io.output():write(···)</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8974 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8975 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8976 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8977 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8978 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8979 <hr><h3><a name="pdf-file:close"><code>file:close ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8980 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8981 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8982 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8983 Closes <code>file</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8984 Note that files are automatically closed when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8985 their handles are garbage collected, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8986 but that takes an unpredictable amount of time to happen. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8987 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8988 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8989 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8990 When closing a file handle created with <a href="#pdf-io.popen"><code>io.popen</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8991 <a href="#pdf-file:close"><code>file:close</code></a> returns the same values |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8992 returned by <a href="#pdf-os.execute"><code>os.execute</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8995 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8996 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8997 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8998 <hr><h3><a name="pdf-file:flush"><code>file:flush ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
8999 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9000 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9001 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9002 Saves any written data to <code>file</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9003 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9004 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9005 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9006 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9007 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9008 <hr><h3><a name="pdf-file:lines"><code>file:lines (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9009 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9010 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9011 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9012 Returns an iterator function that, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9013 each time it is called, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9014 reads the file according to the given formats. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9015 When no format is given, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9016 uses "<code>l</code>" as a default. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9017 As an example, the construction |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9018 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9019 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9020 for c in file:lines(1) do <em>body</em> end |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9021 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9022 will iterate over all characters of the file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9023 starting at the current position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9024 Unlike <a href="#pdf-io.lines"><code>io.lines</code></a>, this function does not close the file |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9025 when the loop ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9026 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9027 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9028 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9029 In case of errors this function raises the error, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9030 instead of returning an error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9031 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9032 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9034 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9035 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9036 <hr><h3><a name="pdf-file:read"><code>file:read (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9037 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9038 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9039 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9040 Reads the file <code>file</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9041 according to the given formats, which specify what to read. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9042 For each format, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9043 the function returns a string or a number with the characters read, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9044 or <b>nil</b> if it cannot read data with the specified format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9045 (In this latter case, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9046 the function does not read subsequent formats.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9047 When called without formats, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9048 it uses a default format that reads the next line |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9049 (see below). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9051 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9052 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9053 The available formats are |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9054 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9055 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9056 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9057 <li><b>"<code>n</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9058 reads a numeral and returns it as a float or an integer, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9059 following the lexical conventions of Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9060 (The numeral may have leading spaces and a sign.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9061 This format always reads the longest input sequence that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9062 is a valid prefix for a number; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9063 if that prefix does not form a valid number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9064 (e.g., an empty string, "<code>0x</code>", or "<code>3.4e-</code>"), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9065 it is discarded and the function returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9066 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9067 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9068 <li><b>"<code>i</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9069 reads an integral number and returns it as an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9070 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9072 <li><b>"<code>a</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9073 reads the whole file, starting at the current position. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9074 On end of file, it returns the empty string. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9075 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9076 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9077 <li><b>"<code>l</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9078 reads the next line skipping the end of line, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9079 returning <b>nil</b> on end of file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9080 This is the default format. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9081 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9082 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9083 <li><b>"<code>L</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9084 reads the next line keeping the end-of-line character (if present), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9085 returning <b>nil</b> on end of file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9086 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9087 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9088 <li><b><em>number</em>: </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9089 reads a string with up to this number of bytes, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9090 returning <b>nil</b> on end of file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9091 If <code>number</code> is zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9092 it reads nothing and returns an empty string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9093 or <b>nil</b> on end of file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9094 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9095 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9096 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9097 The formats "<code>l</code>" and "<code>L</code>" should be used only for text files. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9098 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9099 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9100 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9101 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9102 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9103 <hr><h3><a name="pdf-file:seek"><code>file:seek ([whence [, offset]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9104 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9105 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9106 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9107 Sets and gets the file position, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9108 measured from the beginning of the file, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9109 to the position given by <code>offset</code> plus a base |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9110 specified by the string <code>whence</code>, as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9111 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9112 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9113 <li><b>"<code>set</code>": </b> base is position 0 (beginning of the file);</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9114 <li><b>"<code>cur</code>": </b> base is current position;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9115 <li><b>"<code>end</code>": </b> base is end of file;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9116 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9117 In case of success, <code>seek</code> returns the final file position, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9118 measured in bytes from the beginning of the file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9119 If <code>seek</code> fails, it returns <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9120 plus a string describing the error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9121 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9122 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9123 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9124 The default value for <code>whence</code> is <code>"cur"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9125 and for <code>offset</code> is 0. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9126 Therefore, the call <code>file:seek()</code> returns the current |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9127 file position, without changing it; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9128 the call <code>file:seek("set")</code> sets the position to the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9129 beginning of the file (and returns 0); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9130 and the call <code>file:seek("end")</code> sets the position to the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9131 end of the file, and returns its size. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9132 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9133 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9134 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9135 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9136 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9137 <hr><h3><a name="pdf-file:setvbuf"><code>file:setvbuf (mode [, size])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9138 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9139 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9140 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9141 Sets the buffering mode for an output file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9142 There are three available modes: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9144 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9145 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9146 <li><b>"<code>no</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9147 no buffering; the result of any output operation appears immediately. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9148 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9149 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9150 <li><b>"<code>full</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9151 full buffering; output operation is performed only |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9152 when the buffer is full or when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9153 you explicitly <code>flush</code> the file (see <a href="#pdf-io.flush"><code>io.flush</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9154 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9156 <li><b>"<code>line</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9157 line buffering; output is buffered until a newline is output |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9158 or there is any input from some special files |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9159 (such as a terminal device). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9160 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9161 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9162 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9163 For the last two cases, <code>size</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9164 specifies the size of the buffer, in bytes. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9165 The default is an appropriate size. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9166 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9167 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9168 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9169 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9170 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9171 <hr><h3><a name="pdf-file:write"><code>file:write (···)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9172 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9173 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9174 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9175 Writes the value of each of its arguments to <code>file</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9176 The arguments must be strings or numbers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9177 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9178 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9179 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9180 In case of success, this function returns <code>file</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9181 Otherwise it returns <b>nil</b> plus a string describing the error. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9182 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9183 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9185 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9186 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9187 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9188 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9189 <h2>6.9 – <a name="6.9">Operating System Facilities</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9190 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9191 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9192 This library is implemented through table <a name="pdf-os"><code>os</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9193 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9194 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9195 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9196 <hr><h3><a name="pdf-os.clock"><code>os.clock ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9198 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9199 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9200 Returns an approximation of the amount in seconds of CPU time |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9201 used by the program. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9202 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9203 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9204 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9206 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9207 <hr><h3><a name="pdf-os.date"><code>os.date ([format [, time]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9208 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9210 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9211 Returns a string or a table containing date and time, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9212 formatted according to the given string <code>format</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9214 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9215 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9216 If the <code>time</code> argument is present, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9217 this is the time to be formatted |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9218 (see the <a href="#pdf-os.time"><code>os.time</code></a> function for a description of this value). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9219 Otherwise, <code>date</code> formats the current time. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9220 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9221 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9222 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9223 If <code>format</code> starts with '<code>!</code>', |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9224 then the date is formatted in Coordinated Universal Time. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9225 After this optional character, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9226 if <code>format</code> is the string "<code>*t</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9227 then <code>date</code> returns a table with the following fields: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9228 <code>year</code> (four digits), <code>month</code> (1–12), <code>day</code> (1–31), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9229 <code>hour</code> (0–23), <code>min</code> (0–59), <code>sec</code> (0–61), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9230 <code>wday</code> (weekday, Sunday is 1), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9231 <code>yday</code> (day of the year), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9232 and <code>isdst</code> (daylight saving flag, a boolean). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9233 This last field may be absent |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9234 if the information is not available. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9236 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9237 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9238 If <code>format</code> is not "<code>*t</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9239 then <code>date</code> returns the date as a string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9240 formatted according to the same rules as the ISO C function <code>strftime</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9241 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9242 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9243 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9244 When called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9245 <code>date</code> returns a reasonable date and time representation that depends on |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9246 the host system and on the current locale |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9247 (that is, <code>os.date()</code> is equivalent to <code>os.date("%c")</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9248 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9249 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9250 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9251 On non-POSIX systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9252 this function may be not thread safe |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9253 because of its reliance on C function <code>gmtime</code> and C function <code>localtime</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9254 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9255 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9256 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9257 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9258 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9259 <hr><h3><a name="pdf-os.difftime"><code>os.difftime (t2, t1)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9260 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9261 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9262 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9263 Returns the difference, in seconds, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9264 from time <code>t1</code> to time <code>t2</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9265 (where the times are values returned by <a href="#pdf-os.time"><code>os.time</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9266 In POSIX, Windows, and some other systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9267 this value is exactly <code>t2</code><em>-</em><code>t1</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9268 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9269 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9270 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9271 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9272 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9273 <hr><h3><a name="pdf-os.execute"><code>os.execute ([command])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9274 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9275 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9276 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9277 This function is equivalent to the ISO C function <code>system</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9278 It passes <code>command</code> to be executed by an operating system shell. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9279 Its first result is <b>true</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9280 if the command terminated successfully, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9281 or <b>nil</b> otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9282 After this first result |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9283 the function returns a string plus a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9284 as follows: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9285 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9286 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9287 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9288 <li><b>"<code>exit</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9289 the command terminated normally; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9290 the following number is the exit status of the command. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9291 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9292 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9293 <li><b>"<code>signal</code>": </b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9294 the command was terminated by a signal; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9295 the following number is the signal that terminated the command. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9296 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9297 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9298 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9299 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9300 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9301 When called without a <code>command</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9302 <code>os.execute</code> returns a boolean that is true if a shell is available. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9303 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9304 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9305 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9306 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9307 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9308 <hr><h3><a name="pdf-os.exit"><code>os.exit ([code [, close]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9309 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9310 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9311 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9312 Calls the ISO C function <code>exit</code> to terminate the host program. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9313 If <code>code</code> is <b>true</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9314 the returned status is <code>EXIT_SUCCESS</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9315 if <code>code</code> is <b>false</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9316 the returned status is <code>EXIT_FAILURE</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9317 if <code>code</code> is a number, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9318 the returned status is this number. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9319 The default value for <code>code</code> is <b>true</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9320 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9321 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9322 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9323 If the optional second argument <code>close</code> is true, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9324 closes the Lua state before exiting. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9325 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9326 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9327 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9328 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9329 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9330 <hr><h3><a name="pdf-os.getenv"><code>os.getenv (varname)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9331 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9332 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9333 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9334 Returns the value of the process environment variable <code>varname</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9335 or <b>nil</b> if the variable is not defined. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9336 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9337 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9338 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9339 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9340 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9341 <hr><h3><a name="pdf-os.remove"><code>os.remove (filename)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9342 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9343 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9344 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9345 Deletes the file (or empty directory, on POSIX systems) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9346 with the given name. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9347 If this function fails, it returns <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9348 plus a string describing the error and the error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9349 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9350 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9351 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9352 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9353 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9354 <hr><h3><a name="pdf-os.rename"><code>os.rename (oldname, newname)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9355 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9356 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9357 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9358 Renames file or directory named <code>oldname</code> to <code>newname</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9359 If this function fails, it returns <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9360 plus a string describing the error and the error code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9361 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9362 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9363 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9364 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9365 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9366 <hr><h3><a name="pdf-os.setlocale"><code>os.setlocale (locale [, category])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9367 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9368 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9369 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9370 Sets the current locale of the program. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9371 <code>locale</code> is a system-dependent string specifying a locale; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9372 <code>category</code> is an optional string describing which category to change: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9373 <code>"all"</code>, <code>"collate"</code>, <code>"ctype"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9374 <code>"monetary"</code>, <code>"numeric"</code>, or <code>"time"</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9375 the default category is <code>"all"</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9376 The function returns the name of the new locale, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9377 or <b>nil</b> if the request cannot be honored. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9378 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9379 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9380 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9381 If <code>locale</code> is the empty string, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9382 the current locale is set to an implementation-defined native locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9383 If <code>locale</code> is the string "<code>C</code>", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9384 the current locale is set to the standard C locale. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9385 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9386 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9387 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9388 When called with <b>nil</b> as the first argument, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9389 this function only returns the name of the current locale |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9390 for the given category. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9391 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9392 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9393 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9394 This function may be not thread safe |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9395 because of its reliance on C function <code>setlocale</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9396 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9397 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9398 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9399 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9400 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9401 <hr><h3><a name="pdf-os.time"><code>os.time ([table])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9402 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9403 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9404 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9405 Returns the current time when called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9406 or a time representing the date and time specified by the given table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9407 This table must have fields <code>year</code>, <code>month</code>, and <code>day</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9408 and may have fields |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9409 <code>hour</code> (default is 12), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9410 <code>min</code> (default is 0), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9411 <code>sec</code> (default is 0), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9412 and <code>isdst</code> (default is <b>nil</b>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9413 For a description of these fields, see the <a href="#pdf-os.date"><code>os.date</code></a> function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9414 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9415 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9416 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9417 The returned value is a number, whose meaning depends on your system. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9418 In POSIX, Windows, and some other systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9419 this number counts the number |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9420 of seconds since some given start time (the "epoch"). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9421 In other systems, the meaning is not specified, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9422 and the number returned by <code>time</code> can be used only as an argument to |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9423 <a href="#pdf-os.date"><code>os.date</code></a> and <a href="#pdf-os.difftime"><code>os.difftime</code></a>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9424 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9425 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9426 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9427 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9428 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9429 <hr><h3><a name="pdf-os.tmpname"><code>os.tmpname ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9430 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9431 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9432 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9433 Returns a string with a file name that can |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9434 be used for a temporary file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9435 The file must be explicitly opened before its use |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9436 and explicitly removed when no longer needed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9437 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9438 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9439 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9440 On POSIX systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9441 this function also creates a file with that name, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9442 to avoid security risks. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9443 (Someone else might create the file with wrong permissions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9444 in the time between getting the name and creating the file.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9445 You still have to open the file to use it |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9446 and to remove it (even if you do not use it). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9447 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9448 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9449 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9450 When possible, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9451 you may prefer to use <a href="#pdf-io.tmpfile"><code>io.tmpfile</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9452 which automatically removes the file when the program ends. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9453 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9454 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9455 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9456 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9457 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9458 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9459 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9460 <h2>6.10 – <a name="6.10">The Debug Library</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9461 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9462 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9463 This library provides |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9464 the functionality of the debug interface (<a href="#4.9">§4.9</a>) to Lua programs. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9465 You should exert care when using this library. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9466 Several of its functions |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9467 violate basic assumptions about Lua code |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9468 (e.g., that variables local to a function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9469 cannot be accessed from outside; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9470 that userdata metatables cannot be changed by Lua code; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9471 that Lua programs do not crash) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9472 and therefore can compromise otherwise secure code. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9473 Moreover, some functions in this library may be slow. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9474 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9475 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9476 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9477 All functions in this library are provided |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9478 inside the <a name="pdf-debug"><code>debug</code></a> table. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9479 All functions that operate over a thread |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9480 have an optional first argument which is the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9481 thread to operate over. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9482 The default is always the current thread. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9483 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9484 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9485 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9486 <hr><h3><a name="pdf-debug.debug"><code>debug.debug ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9487 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9488 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9489 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9490 Enters an interactive mode with the user, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9491 running each string that the user enters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9492 Using simple commands and other debug facilities, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9493 the user can inspect global and local variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9494 change their values, evaluate expressions, and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9495 A line containing only the word <code>cont</code> finishes this function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9496 so that the caller continues its execution. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9497 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9498 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9499 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9500 Note that commands for <code>debug.debug</code> are not lexically nested |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9501 within any function and so have no direct access to local variables. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9502 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9503 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9504 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9505 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9506 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9507 <hr><h3><a name="pdf-debug.gethook"><code>debug.gethook ([thread])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9508 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9509 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9510 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9511 Returns the current hook settings of the thread, as three values: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9512 the current hook function, the current hook mask, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9513 and the current hook count |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9514 (as set by the <a href="#pdf-debug.sethook"><code>debug.sethook</code></a> function). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9515 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9516 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9517 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9518 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9519 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9520 <hr><h3><a name="pdf-debug.getinfo"><code>debug.getinfo ([thread,] f [, what])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9521 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9522 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9523 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9524 Returns a table with information about a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9525 You can give the function directly |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9526 or you can give a number as the value of <code>f</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9527 which means the function running at level <code>f</code> of the call stack |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9528 of the given thread: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9529 level 0 is the current function (<code>getinfo</code> itself); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9530 level 1 is the function that called <code>getinfo</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9531 (except for tail calls, which do not count on the stack); |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9532 and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9533 If <code>f</code> is a number larger than the number of active functions, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9534 then <code>getinfo</code> returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9535 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9536 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9537 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9538 The returned table can contain all the fields returned by <a href="#lua_getinfo"><code>lua_getinfo</code></a>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9539 with the string <code>what</code> describing which fields to fill in. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9540 The default for <code>what</code> is to get all information available, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9541 except the table of valid lines. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9542 If present, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9543 the option '<code>f</code>' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9544 adds a field named <code>func</code> with the function itself. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9545 If present, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9546 the option '<code>L</code>' |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9547 adds a field named <code>activelines</code> with the table of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9548 valid lines. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9549 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9550 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9551 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9552 For instance, the expression <code>debug.getinfo(1,"n").name</code> returns |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9553 a table with a name for the current function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9554 if a reasonable name can be found, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9555 and the expression <code>debug.getinfo(print)</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9556 returns a table with all available information |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9557 about the <a href="#pdf-print"><code>print</code></a> function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9558 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9559 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9560 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9561 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9562 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9563 <hr><h3><a name="pdf-debug.getlocal"><code>debug.getlocal ([thread,] f, local)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9564 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9565 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9566 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9567 This function returns the name and the value of the local variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9568 with index <code>local</code> of the function at level <code>f</code> of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9569 This function accesses not only explicit local variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9570 but also parameters, temporaries, etc. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9571 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9572 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9573 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9574 The first parameter or local variable has index 1, and so on, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9575 following the order that they are declared in the code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9576 counting only the variables that are active |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9577 in the current scope of the function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9578 Negative indices refer to vararg parameters; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9579 -1 is the first vararg parameter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9580 The function returns <b>nil</b> if there is no variable with the given index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9581 and raises an error when called with a level out of range. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9582 (You can call <a href="#pdf-debug.getinfo"><code>debug.getinfo</code></a> to check whether the level is valid.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9583 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9584 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9585 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9586 Variable names starting with '<code>(</code>' (open parenthesis) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9587 represent variables with no known names |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9588 (internal variables such as loop control variables, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9589 and variables from chunks saved without debug information). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9590 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9591 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9592 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9593 The parameter <code>f</code> may also be a function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9594 In that case, <code>getlocal</code> returns only the name of function parameters. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9595 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9596 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9597 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9598 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9599 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9600 <hr><h3><a name="pdf-debug.getmetatable"><code>debug.getmetatable (value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9601 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9602 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9603 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9604 Returns the metatable of the given <code>value</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9605 or <b>nil</b> if it does not have a metatable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9606 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9607 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9608 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9609 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9610 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9611 <hr><h3><a name="pdf-debug.getregistry"><code>debug.getregistry ()</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9612 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9613 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9614 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9615 Returns the registry table (see <a href="#4.5">§4.5</a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9616 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9617 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9618 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9619 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9620 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9621 <hr><h3><a name="pdf-debug.getupvalue"><code>debug.getupvalue (f, up)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9622 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9623 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9624 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9625 This function returns the name and the value of the upvalue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9626 with index <code>up</code> of the function <code>f</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9627 The function returns <b>nil</b> if there is no upvalue with the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9628 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9629 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9630 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9631 Variable names starting with '<code>(</code>' (open parenthesis) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9632 represent variables with no known names |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9633 (variables from chunks saved without debug information). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9634 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9635 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9636 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9637 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9638 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9639 <hr><h3><a name="pdf-debug.getuservalue"><code>debug.getuservalue (u)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9640 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9641 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9642 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9643 Returns the Lua value associated to <code>u</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9644 If <code>u</code> is not a userdata, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9645 returns <b>nil</b>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9646 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9647 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9648 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9649 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9650 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9651 <hr><h3><a name="pdf-debug.sethook"><code>debug.sethook ([thread,] hook, mask [, count])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9652 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9653 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9654 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9655 Sets the given function as a hook. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9656 The string <code>mask</code> and the number <code>count</code> describe |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9657 when the hook will be called. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9658 The string mask may have any combination of the following characters, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9659 with the given meaning: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9660 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9661 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9662 <li><b>'<code>c</code>': </b> the hook is called every time Lua calls a function;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9663 <li><b>'<code>r</code>': </b> the hook is called every time Lua returns from a function;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9664 <li><b>'<code>l</code>': </b> the hook is called every time Lua enters a new line of code.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9665 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9666 Moreover, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9667 with a <code>count</code> different from zero, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9668 the hook is called also after every <code>count</code> instructions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9669 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9670 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9671 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9672 When called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9673 <a href="#pdf-debug.sethook"><code>debug.sethook</code></a> turns off the hook. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9674 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9675 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9676 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9677 When the hook is called, its first parameter is a string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9678 describing the event that has triggered its call: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9679 <code>"call"</code> (or <code>"tail call"</code>), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9680 <code>"return"</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9681 <code>"line"</code>, and <code>"count"</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9682 For line events, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9683 the hook also gets the new line number as its second parameter. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9684 Inside a hook, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9685 you can call <code>getinfo</code> with level 2 to get more information about |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9686 the running function |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9687 (level 0 is the <code>getinfo</code> function, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9688 and level 1 is the hook function). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9689 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9690 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9691 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9692 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9693 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9694 <hr><h3><a name="pdf-debug.setlocal"><code>debug.setlocal ([thread,] level, local, value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9695 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9696 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9697 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9698 This function assigns the value <code>value</code> to the local variable |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9699 with index <code>local</code> of the function at level <code>level</code> of the stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9700 The function returns <b>nil</b> if there is no local |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9701 variable with the given index, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9702 and raises an error when called with a <code>level</code> out of range. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9703 (You can call <code>getinfo</code> to check whether the level is valid.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9704 Otherwise, it returns the name of the local variable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9705 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9706 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9707 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9708 See <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for more information about |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9709 variable indices and names. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9710 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9711 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9712 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9713 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9714 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9715 <hr><h3><a name="pdf-debug.setmetatable"><code>debug.setmetatable (value, table)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9716 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9717 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9718 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9719 Sets the metatable for the given <code>value</code> to the given <code>table</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9720 (which can be <b>nil</b>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9721 Returns <code>value</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9722 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9723 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9724 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9725 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9726 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9727 <hr><h3><a name="pdf-debug.setupvalue"><code>debug.setupvalue (f, up, value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9728 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9729 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9730 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9731 This function assigns the value <code>value</code> to the upvalue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9732 with index <code>up</code> of the function <code>f</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9733 The function returns <b>nil</b> if there is no upvalue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9734 with the given index. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9735 Otherwise, it returns the name of the upvalue. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9736 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9737 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9738 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9739 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9740 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9741 <hr><h3><a name="pdf-debug.setuservalue"><code>debug.setuservalue (udata, value)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9742 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9743 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9744 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9745 Sets the given <code>value</code> as |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9746 the Lua value associated to the given <code>udata</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9747 <code>udata</code> must be a full userdata. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9748 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9749 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9750 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9751 Returns <code>udata</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9752 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9753 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9754 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9755 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9756 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9757 <hr><h3><a name="pdf-debug.traceback"><code>debug.traceback ([thread,] [message [, level]])</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9758 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9759 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9760 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9761 If <code>message</code> is present but is neither a string nor <b>nil</b>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9762 this function returns <code>message</code> without further processing. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9763 Otherwise, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9764 it returns a string with a traceback of the call stack. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9765 The optional <code>message</code> string is appended |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9766 at the beginning of the traceback. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9767 An optional <code>level</code> number tells at which level |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9768 to start the traceback |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9769 (default is 1, the function calling <code>traceback</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9770 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9771 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9772 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9773 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9774 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9775 <hr><h3><a name="pdf-debug.upvalueid"><code>debug.upvalueid (f, n)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9776 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9777 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9778 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9779 Returns a unique identifier (as a light userdata) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9780 for the upvalue numbered <code>n</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9781 from the given function. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9782 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9783 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9784 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9785 These unique identifiers allow a program to check whether different |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9786 closures share upvalues. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9787 Lua closures that share an upvalue |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9788 (that is, that access a same external local variable) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9789 will return identical ids for those upvalue indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9790 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9791 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9792 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9793 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9794 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9795 <hr><h3><a name="pdf-debug.upvaluejoin"><code>debug.upvaluejoin (f1, n1, f2, n2)</code></a></h3> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9796 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9797 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9798 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9799 Make the <code>n1</code>-th upvalue of the Lua closure <code>f1</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9800 refer to the <code>n2</code>-th upvalue of the Lua closure <code>f2</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9801 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9802 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9803 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9804 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9805 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9806 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9807 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9808 <h1>7 – <a name="7">Lua Standalone</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9809 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9810 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9811 Although Lua has been designed as an extension language, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9812 to be embedded in a host C program, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9813 it is also frequently used as a standalone language. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9814 An interpreter for Lua as a standalone language, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9815 called simply <code>lua</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9816 is provided with the standard distribution. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9817 The standalone interpreter includes |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9818 all standard libraries, including the debug library. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9819 Its usage is: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9820 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9821 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9822 lua [options] [script [args]] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9823 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9824 The options are: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9825 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9826 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9827 <li><b><code>-e <em>stat</em></code>: </b> executes string <em>stat</em>;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9828 <li><b><code>-l <em>mod</em></code>: </b> "requires" <em>mod</em>;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9829 <li><b><code>-i</code>: </b> enters interactive mode after running <em>script</em>;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9830 <li><b><code>-v</code>: </b> prints version information;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9831 <li><b><code>-E</code>: </b> ignores environment variables;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9832 <li><b><code>--</code>: </b> stops handling options;</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9833 <li><b><code>-</code>: </b> executes <code>stdin</code> as a file and stops handling options.</li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9834 </ul><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9835 After handling its options, <code>lua</code> runs the given <em>script</em>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9836 When called without arguments, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9837 <code>lua</code> behaves as <code>lua -v -i</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9838 when the standard input (<code>stdin</code>) is a terminal, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9839 and as <code>lua -</code> otherwise. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9840 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9841 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9842 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9843 When called without option <code>-E</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9844 the interpreter checks for an environment variable <a name="pdf-LUA_INIT_5_3"><code>LUA_INIT_5_3</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9845 (or <a name="pdf-LUA_INIT"><code>LUA_INIT</code></a> if the versioned name is not defined) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9846 before running any argument. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9847 If the variable content has the format <code>@<em>filename</em></code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9848 then <code>lua</code> executes the file. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9849 Otherwise, <code>lua</code> executes the string itself. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9850 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9851 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9852 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9853 When called with option <code>-E</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9854 besides ignoring <code>LUA_INIT</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9855 Lua also ignores |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9856 the values of <code>LUA_PATH</code> and <code>LUA_CPATH</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9857 setting the values of |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9858 <a href="#pdf-package.path"><code>package.path</code></a> and <a href="#pdf-package.cpath"><code>package.cpath</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9859 with the default paths defined in <code>luaconf.h</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9860 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9861 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9862 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9863 All options are handled in order, except <code>-i</code> and <code>-E</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9864 For instance, an invocation like |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9865 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9866 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9867 $ lua -e'a=1' -e 'print(a)' script.lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9868 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9869 will first set <code>a</code> to 1, then print the value of <code>a</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9870 and finally run the file <code>script.lua</code> with no arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9871 (Here <code>$</code> is the shell prompt. Your prompt may be different.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9872 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9873 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9874 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9875 Before running any code, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9876 <code>lua</code> collects all command-line arguments |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9877 in a global table called <code>arg</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9878 The script name goes to index 0, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9879 the first argument after the script name goes to index 1, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9880 and so on. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9881 Any arguments before the script name |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9882 (that is, the interpreter name plus its options) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9883 go to negative indices. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9884 For instance, in the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9885 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9886 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9887 $ lua -la b.lua t1 t2 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9888 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9889 the table is like this: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9890 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9891 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9892 arg = { [-2] = "lua", [-1] = "-la", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9893 [0] = "b.lua", |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9894 [1] = "t1", [2] = "t2" } |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9895 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9896 If there is no script in the call, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9897 the interpreter name goes to index 0, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9898 followed by the other arguments. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9899 For instance, the call |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9900 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9901 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9902 $ lua -e "print(arg[1])" |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9903 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9904 will print "<code>-e</code>". |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9905 If there is a script, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9906 the script is called with parameters |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9907 <code>arg[1]</code>, ···, <code>arg[#arg]</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9908 (Like all chunks in Lua, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9909 the script is compiled as a vararg function.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9910 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9911 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9912 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9913 In interactive mode, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9914 Lua repeatedly prompts and waits for a line. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9915 After reading a line, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9916 Lua first try to interpret the line as an expression. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9917 If it succeeds, it prints its value. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9918 Otherwise, it interprets the line as a statement. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9919 If you write an incomplete statement, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9920 the interpreter waits for its completion |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9921 by issuing a different prompt. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9922 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9923 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9924 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9925 In case of unprotected errors in the script, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9926 the interpreter reports the error to the standard error stream. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9927 If the error object is not a string but |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9928 has a metamethod <code>__tostring</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9929 the interpreter calls this metamethod to produce the final message. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9930 Otherwise, the interpreter converts the error object to a string |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9931 and adds a stack traceback to it. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9932 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9933 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9934 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9935 When finishing normally, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9936 the interpreter closes its main Lua state |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9937 (see <a href="#lua_close"><code>lua_close</code></a>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9938 The script can avoid this step by |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9939 calling <a href="#pdf-os.exit"><code>os.exit</code></a> to terminate. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9940 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9941 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9942 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9943 To allow the use of Lua as a |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9944 script interpreter in Unix systems, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9945 the standalone interpreter skips |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9946 the first line of a chunk if it starts with <code>#</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9947 Therefore, Lua scripts can be made into executable programs |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9948 by using <code>chmod +x</code> and the <code>#!</code> form, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9949 as in |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9950 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9951 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9952 #!/usr/local/bin/lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9953 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9954 (Of course, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9955 the location of the Lua interpreter may be different in your machine. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9956 If <code>lua</code> is in your <code>PATH</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9957 then |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9958 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9959 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9960 #!/usr/bin/env lua |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9961 </pre><p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9962 is a more portable solution.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9963 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9964 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9965 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9966 <h1>8 – <a name="8">Incompatibilities with the Previous Version</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9967 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9968 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9969 Here we list the incompatibilities that you may find when moving a program |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9970 from Lua 5.2 to Lua 5.3. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9971 You can avoid some incompatibilities by compiling Lua with |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9972 appropriate options (see file <code>luaconf.h</code>). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9973 However, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9974 all these compatibility options will be removed in the future. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9975 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9976 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9977 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9978 Lua versions can always change the C API in ways that |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9979 do not imply source-code changes in a program, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9980 such as the numeric values for constants |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9981 or the implementation of functions as macros. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9982 Therefore, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9983 you should not assume that binaries are compatible between |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9984 different Lua versions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9985 Always recompile clients of the Lua API when |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9986 using a new version. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9987 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9988 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9989 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9990 Similarly, Lua versions can always change the internal representation |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9991 of precompiled chunks; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9992 precompiled chunks are not compatible between different Lua versions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9993 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9994 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9995 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9996 The standard paths in the official distribution may |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9997 change between versions. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9998 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
9999 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10000 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10001 <h2>8.1 – <a name="8.1">Changes in the Language</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10002 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10003 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10004 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10005 The main difference between Lua 5.2 and Lua 5.3 is the |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10006 introduction of an integer subtype for numbers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10007 Although this change should not affect "normal" computations, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10008 some computations |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10009 (mainly those that involve some kind of overflow) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10010 can give different results. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10011 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10012 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10013 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10014 You can fix these differences by forcing a number to be a float |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10015 (in Lua 5.2 all numbers were float), |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10016 in particular writing constants with an ending <code>.0</code> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10017 or using <code>x = x + 0.0</code> to convert a variable. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10018 (This recommendation is only for a quick fix |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10019 for an occasional incompatibility; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10020 it is not a general guideline for good programming. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10021 For good programming, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10022 use floats where you need floats |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10023 and integers where you need integers.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10024 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10025 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10026 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10027 The conversion of a float to a string now adds a <code>.0</code> suffix |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10028 to the result if it looks like an integer. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10029 (For instance, the float 2.0 will be printed as <code>2.0</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10030 not as <code>2</code>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10031 You should always use an explicit format |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10032 when you need a specific format for numbers. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10033 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10034 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10035 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10036 (Formally this is not an incompatibility, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10037 because Lua does not specify how numbers are formatted as strings, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10038 but some programs assumed a specific format.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10039 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10040 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10041 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10042 The generational mode for the garbage collector was removed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10043 (It was an experimental feature in Lua 5.2.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10044 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10045 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10046 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10047 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10048 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10049 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10050 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10051 <h2>8.2 – <a name="8.2">Changes in the Libraries</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10052 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10053 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10054 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10055 The <code>bit32</code> library has been deprecated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10056 It is easy to require a compatible external library or, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10057 better yet, to replace its functions with appropriate bitwise operations. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10058 (Keep in mind that <code>bit32</code> operates on 32-bit integers, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10059 while the bitwise operators in standard Lua operate on 64-bit integers.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10060 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10061 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10062 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10063 The Table library now respects metamethods |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10064 for setting and getting elements. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10065 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10066 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10067 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10068 The <a href="#pdf-ipairs"><code>ipairs</code></a> iterator now respects metamethods and |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10069 its <code>__ipairs</code> metamethod has been deprecated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10070 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10071 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10072 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10073 Option names in <a href="#pdf-io.read"><code>io.read</code></a> do not have a starting '<code>*</code>' anymore. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10074 For compatibility, Lua will continue to ignore this character. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10075 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10076 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10077 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10078 The following functions were deprecated in the mathematical library: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10079 <code>atan2</code>, <code>cosh</code>, <code>sinh</code>, <code>tanh</code>, <code>pow</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10080 <code>frexp</code>, and <code>ldexp</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10081 You can replace <code>math.pow(x,y)</code> with <code>x^y</code>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10082 you can replace <code>math.atan2</code> with <code>math.atan</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10083 which now accepts one or two parameters; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10084 you can replace <code>math.ldexp(x,exp)</code> with <code>x * 2.0^exp</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10085 For the other operations, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10086 you can either use an external library or |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10087 implement them in Lua. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10088 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10089 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10090 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10091 The searcher for C loaders used by <a href="#pdf-require"><code>require</code></a> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10092 changed the way it handles versioned names. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10093 Now, the version should come after the module name |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10094 (as is usual in most other tools). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10095 For compatibility, that searcher still tries the old format |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10096 if it cannot find an open function according to the new style. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10097 (Lua 5.2 already worked that way, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10098 but it did not document the change.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10099 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10100 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10101 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10102 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10103 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10104 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10105 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10106 <h2>8.3 – <a name="8.3">Changes in the API</a></h2> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10107 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10108 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10109 <ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10110 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10111 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10112 Continuation functions now receive as parameters what they needed |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10113 to get through <code>lua_getctx</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10114 so <code>lua_getctx</code> has been removed. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10115 Adapt your code accordingly. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10116 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10117 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10118 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10119 Function <a href="#lua_dump"><code>lua_dump</code></a> has an extra parameter, <code>strip</code>. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10120 Use 0 as the value of this parameter to get the old behavior. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10121 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10122 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10123 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10124 Functions to inject/project unsigned integers |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10125 (<code>lua_pushunsigned</code>, <code>lua_tounsigned</code>, <code>lua_tounsignedx</code>, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10126 <code>luaL_checkunsigned</code>, <code>luaL_optunsigned</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10127 were deprecated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10128 Use their signed equivalents with a type cast. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10129 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10130 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10131 <li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10132 Macros to project non-default integer types |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10133 (<code>luaL_checkint</code>, <code>luaL_optint</code>, <code>luaL_checklong</code>, <code>luaL_optlong</code>) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10134 were deprecated. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10135 Use their equivalent over <a href="#lua_Integer"><code>lua_Integer</code></a> with a type cast |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10136 (or, when possible, use <a href="#lua_Integer"><code>lua_Integer</code></a> in your code). |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10137 </li> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10138 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10139 </ul> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10140 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10141 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10142 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10143 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10144 <h1>9 – <a name="9">The Complete Syntax of Lua</a></h1> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10145 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10146 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10147 Here is the complete syntax of Lua in extended BNF. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10148 As usual in extended BNF, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10149 {A} means 0 or more As, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10150 and [A] means an optional A. |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10151 (For operator precedences, see <a href="#3.4.8">§3.4.8</a>; |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10152 for a description of the terminals |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10153 Name, Numeral, |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10154 and LiteralString, see <a href="#3.1">§3.1</a>.) |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10155 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10156 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10157 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10158 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10159 <pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10160 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10161 chunk ::= block |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10162 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10163 block ::= {stat} [retstat] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10164 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10165 stat ::= ‘<b>;</b>’ | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10166 varlist ‘<b>=</b>’ explist | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10167 functioncall | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10168 label | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10169 <b>break</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10170 <b>goto</b> Name | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10171 <b>do</b> block <b>end</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10172 <b>while</b> exp <b>do</b> block <b>end</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10173 <b>repeat</b> block <b>until</b> exp | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10174 <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10175 <b>for</b> Name ‘<b>=</b>’ exp ‘<b>,</b>’ exp [‘<b>,</b>’ exp] <b>do</b> block <b>end</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10176 <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b> | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10177 <b>function</b> funcname funcbody | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10178 <b>local</b> <b>function</b> Name funcbody | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10179 <b>local</b> namelist [‘<b>=</b>’ explist] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10180 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10181 retstat ::= <b>return</b> [explist] [‘<b>;</b>’] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10182 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10183 label ::= ‘<b>::</b>’ Name ‘<b>::</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10184 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10185 funcname ::= Name {‘<b>.</b>’ Name} [‘<b>:</b>’ Name] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10186 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10187 varlist ::= var {‘<b>,</b>’ var} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10188 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10189 var ::= Name | prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’ | prefixexp ‘<b>.</b>’ Name |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10190 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10191 namelist ::= Name {‘<b>,</b>’ Name} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10192 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10193 explist ::= exp {‘<b>,</b>’ exp} |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10194 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10195 exp ::= <b>nil</b> | <b>false</b> | <b>true</b> | Numeral | LiteralString | ‘<b>...</b>’ | functiondef | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10196 prefixexp | tableconstructor | exp binop exp | unop exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10197 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10198 prefixexp ::= var | functioncall | ‘<b>(</b>’ exp ‘<b>)</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10199 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10200 functioncall ::= prefixexp args | prefixexp ‘<b>:</b>’ Name args |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10201 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10202 args ::= ‘<b>(</b>’ [explist] ‘<b>)</b>’ | tableconstructor | LiteralString |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10203 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10204 functiondef ::= <b>function</b> funcbody |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10205 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10206 funcbody ::= ‘<b>(</b>’ [parlist] ‘<b>)</b>’ block <b>end</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10207 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10208 parlist ::= namelist [‘<b>,</b>’ ‘<b>...</b>’] | ‘<b>...</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10209 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10210 tableconstructor ::= ‘<b>{</b>’ [fieldlist] ‘<b>}</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10211 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10212 fieldlist ::= field {fieldsep field} [fieldsep] |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10213 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10214 field ::= ‘<b>[</b>’ exp ‘<b>]</b>’ ‘<b>=</b>’ exp | Name ‘<b>=</b>’ exp | exp |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10215 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10216 fieldsep ::= ‘<b>,</b>’ | ‘<b>;</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10217 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10218 binop ::= ‘<b>+</b>’ | ‘<b>-</b>’ | ‘<b>*</b>’ | ‘<b>/</b>’ | ‘<b>//</b>’ | ‘<b>^</b>’ | ‘<b>%</b>’ | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10219 ‘<b>&</b>’ | ‘<b>~</b>’ | ‘<b>|</b>’ | ‘<b>>></b>’ | ‘<b><<</b>’ | ‘<b>..</b>’ | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10220 ‘<b><</b>’ | ‘<b><=</b>’ | ‘<b>></b>’ | ‘<b>>=</b>’ | ‘<b>==</b>’ | ‘<b>~=</b>’ | |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10221 <b>and</b> | <b>or</b> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10222 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10223 unop ::= ‘<b>-</b>’ | <b>not</b> | ‘<b>#</b>’ | ‘<b>~</b>’ |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10224 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10225 </pre> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10226 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10227 <p> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10228 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10229 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10230 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10231 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10232 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10233 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10234 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10235 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10236 <HR> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10237 <SMALL CLASS="footer"> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10238 Last update: |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10239 Fri Jan 16 00:58:20 BRST 2015 |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10240 </SMALL> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10241 <!-- |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10242 Last change: minor edit |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10243 --> |
|
e01cddba3433
add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff
changeset
|
10244 |
| 372 | 10245 </div> |
|
386
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
10246 |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
10247 <% end; |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
10248 } |
|
db23f654f87d
make all of website use luan
Franklin Schmidt <fschmidt@gmail.com>
parents:
382
diff
changeset
|
10249 end |