repo/luan: website/src/manual.html annotate

annotate website/src/manual.html @ 1636:8efb10bf569a

remove duplicate files

author	fffilimonov
date	Wed, 15 Dec 2021 08:26:29 +0000
parents	d3e61cd2aca0
children	0af6a9d6d12f

rev	line source
1216 5dbb552075ff doctype Franklin Schmidt <fschmidt@gmail.com> parents: 1195 diff changeset	1 <!doctype html>
391 2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	2 <html>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	3 <head>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	4 <title>Luan Reference Manual</title>
1521 d3e61cd2aca0 docs and shell bug fix Franklin Schmidt <fschmidt@gmail.com> parents: 1520 diff changeset	5 <meta name="viewport" content="width=device-width, initial-scale=1">
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	6 <style>
1326 29d6d7d79c41 website - use relative paths Franklin Schmidt <fschmidt@gmail.com> parents: 1325 diff changeset	7 @import "site.css";
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	8 </style>
391 2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	9 </head>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	10 <body>
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	11
1326 29d6d7d79c41 website - use relative paths Franklin Schmidt <fschmidt@gmail.com> parents: 1325 diff changeset	12 <div small>
29d6d7d79c41 website - use relative paths Franklin Schmidt <fschmidt@gmail.com> parents: 1325 diff changeset	13 <a href=".">Luan</a>
29d6d7d79c41 website - use relative paths Franklin Schmidt <fschmidt@gmail.com> parents: 1325 diff changeset	14 / <a href="docs.html">Documentation</a>
29d6d7d79c41 website - use relative paths Franklin Schmidt <fschmidt@gmail.com> parents: 1325 diff changeset	15 </div>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	16
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	17 <h1><a href="manual.html">Luan Reference Manual</a></h1>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	18
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	19 <p small>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	20 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	21 Freely available under the terms of the
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	22 <a href="http://www.lua.org/license.html">Lua license</a>.
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	23 Modified for Luan.
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	24 </p>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	25
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	26 <hr/>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	27
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	28 <h2>Contents</h2>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	29
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	30 <div contents><a href="#intro">Introduction</a></div>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	31
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	32 <div contents>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	33 <a href="#basic">Basic Concepts</a>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	34 <ul>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	35 <li><a href="#types">Values and Types</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	36 <li><a href="#env">Environments</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	37 <li><a href="#error">Error Handling</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	38 <li><a href="#meta">Metatables and Metamethods</a></li>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	39 <li><a href="#gc">Garbage Collection</a></li>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	40 </ul>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	41 </div>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	42
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	43 <div contents>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	44 <a href="#lang">The Language</a>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	45 <ul>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	46 <li><a href="#lex">Lexical Conventions</a></li>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	47 <li><a href="#vars">Variables</a></li>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	48 <li>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	49 <a href="#stmts">Statements</a>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	50 <ul>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	51 <li><a href="#blocks">Blocks</a></li>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	52 <li><a href="#chunks">Chunks</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	53 <li><a href="#assignment">Assignment</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	54 <li><a href="#control">Control Structures</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	55 <li><a href="#for">For Statement</a></li>
1520 d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	56 <li><a href="#try">Try Statement</a></li>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	57 <li><a href="#fn_stmt">Function Calls as Statements</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	58 <li><a href="#local_stmt">Local Declarations</a></li>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	59 <li><a href="#template_stmt">Template Statements</a></li>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	60 </ul>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	61 </li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	62 <li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	63 <a href="#expressions">Expressions</a>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	64 <ul>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	65 <li><a href="#arithmetic">Arithmetic Operators</a></li>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	66 <li><a href="#conversions">Coercions and Conversions</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	67 <li><a href="#relational">Relational Operators</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	68 <li><a href="#logical_ops">Logical Operators</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	69 <li><a href="#concatenation">Concatenation</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	70 <li><a href="#length">The Length Operator</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	71 <li><a href="#precedence">Precedence</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	72 <li><a href="#constructors">Table Constructors</a></li>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	73 <li><a href="#fn_calls">Function Calls</a></li>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	74 <li><a href="#fn_def">Function Definitions</a></li>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	75 </ul>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	76 </li>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	77 <li><a href="#visibility">Visibility Rules</a></li>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	78 </ul>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	79 </div>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	80
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	81 <div contents>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	82 <a href="#libs">Standard Libraries</a>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	83 <ul>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	84 <li><a href="#default_lib">Default Environment</a></li>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	85 <li><a href="#luan_lib">Basic Functions</a></li>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	86 <li><a href="#package_lib">Modules</a></li>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	87 <li><a href="#string_lib">String Manipulation</a></li>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	88 <li><a href="#binary_lib">Binary Manipulation</a></li>
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	89 <li><a href="#table_lib">Table Manipulation</a></li>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	90 <li><a href="#number_lib">Number Manipulation</a></li>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	91 <li><a href="#math_lib">Mathematical Functions</a></li>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	92 </ul>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	93 </div>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	94
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	95 <hr/>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	96
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	97
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	98 <h2 heading><a name="intro" href="#intro">Introduction</a></h2>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	99
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	100 <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>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	101
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	102 <p>Luan is implemented in Java and is tightly coupled with Java. So it makes a great scripting language for Java programmers.</p>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	103
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	104 <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	105
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	106
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	107 <h2 heading><a name="basic" href="#basic">Basic Concepts</a></h2>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	108
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	109 <p>This section describes the basic concepts of the language.</p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	110
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	111 <h3 heading><a name="types" href="#types">Values and Types</a></h3>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	112
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	113 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	114 Luan is a <em>dynamically typed language</em>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	115 This means that
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	116 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	117 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	118 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	119
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	121 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	122 All values in Luan are <em>first-class values</em>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	123 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	124 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	125
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	126
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	127 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	128 There are eight basic types in Luan:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	129 <em>nil</em>, <em>boolean</em>, <em>number</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	130 <em>string</em>, <em>binary</em>, <em>function</em>, <em>java</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	131 and <em>table</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	132 <em>Nil</em> 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	133 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	134 it usually represents the absence of a useful value.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	135 <em>Nil</em> is implemented as the Java value <em>null</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	136 <em>Boolean</em> is the type of the values <b>false</b> and <b>true</b>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	137 <em>Boolean</em> is implemented as the Java class <em>Boolean</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	138 <em>Number</em> represents both
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	139 integer numbers and real (floating-point) numbers.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	140 <em>Number</em> is implemented as the Java class <em>Number</em>. Any Java subclass of <em>Number</em> is allowed and this is invisible to the Luan user. Operations on numbers follow the same rules of
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	141 the underlying Java implementation.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	142
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	143 <em>String</em> is implemented as the Java class <em>String</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	144 <em>Binary</em> is implemented as the Java type <em>byte[]</em>.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	145
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	146
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	147 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	148 Luan can call (and manipulate) functions written in Luan and
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	149 functions written in Java (see <a href="#fn_calls">Function Calls</a>).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	150 Both are represented by the type <em>function</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	151
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	152
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	153 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	154 The type <em>java</em> is provided to allow arbitrary Java objects to
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	155 be stored in Luan variables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	156 A <em>java</em> value is a Java object that isn't one of the standard Luan types.
513 0dfc01d8d42d rename type "userdata" to "java" Franklin Schmidt <fschmidt@gmail.com> parents: 512 diff changeset	157 Java values have 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	158 except assignment and identity test.
513 0dfc01d8d42d rename type "userdata" to "java" Franklin Schmidt <fschmidt@gmail.com> parents: 512 diff changeset	159 Java values are useful when Java access is enabled in Luan
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	160
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	161
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	162
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	163 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	164 The type <em>table</em> implements associative arrays,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	165 that is, arrays that can be indexed not only with numbers,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	166 but with any Luan value except <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	167 Tables can be <em>heterogeneous</em>;
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	168 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	169 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	170 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	171 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	172
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	173
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	174 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	175 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	176 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	177 symbol tables, sets, records, graphs, trees, etc.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	178 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	179 The language supports this representation by
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	180 providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	181 There are several convenient ways to create tables in Luan
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	182 (see <a href="#constructors">Table Constructors</a>).
371 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 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	186 We use the term <em>sequence</em> to denote a table where
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	187 the set of all positive numeric keys is equal to {1..<em>n</em>}
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	188 for some non-negative integer <em>n</em>,
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	189 which is called the length of the sequence (see <a href="#length">The Length Operator</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	190
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	191
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	192 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	193 Like indices,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	194 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	195 In particular,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	196 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	197 table fields can contain functions.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	198 Thus tables can also carry <em>methods</em> (see <a href="#fn_def">Function Definitions</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	200
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	201 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	202 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	203 the definition of raw equality in the language.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	204 The expressions <code>a[i]</code> and <code>a[j]</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	205 denote the same table element
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	206 if and only if <code>i</code> and <code>j</code> are raw equal
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	207 (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	208 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	209 are equal to their respective integers
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	210 (e.g., <code>1.0 == 1</code>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	211
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	212
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	213 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	214 Luan values are <em>objects</em>:
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	215 variables do not actually <em>contain</em> values,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	216 only <em>references</em> to them.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	217 Assignment, parameter passing, and function returns
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	218 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	219 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	220
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	221
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	222 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	223 The library function <a href="#Luan.type"><code>Luan.type</code></a> returns a string describing the type
478 eb6d90fb0b5c documentation Franklin Schmidt <fschmidt@gmail.com> parents: 476 diff changeset	224 of a given value.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	226
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	227
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	229
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	230 <h3 heading><a name="env" href="#env">Environments</a></h3>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	231
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	232 <p>
1353 8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	233 The environment of a chunk starts with only one local variable: <code><a href="#require">require</a></code>. This function is used to load and access libraries and other modules. All other variables must be added to the environment using <a href="http://localhost:8080/manual.html#local_stmt">local declarations</a>.
512 d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	234
d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	235 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	236 As will be discussed in <a href="#vars">Variables</a> and <a href=#assignment">Assignment</a>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	237 any reference to a free name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	238 (that is, a name not bound to any declaration) <code>var</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	239 can be syntactically translated to <code>_ENV.var</code> if <code>_ENV</code> is defined.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	240
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	241
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	242 <h3 heading><a name="error" href="#error">Error Handling</a></h3>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	243
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	244 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	245 Luan code can explicitly generate an error by calling the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	246 <a href="#Luan.error"><code>error</code></a> function.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	247 If you need to catch errors in Luan,
1520 d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	248 you can use the <a href="#try">Try Statement</code></a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	249
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	250
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	251 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	252 Whenever there is an error,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	253 an <em>error table</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	254 is propagated with information about the error.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	255 See <a href="#Luan.new_error"><code>Luan.new_error</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	256
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	257
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	258
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	259 <h3 heading><a name="meta" href="#meta">Metatables and Metamethods</a></h3>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	260
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	261 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	262 Every table in Luan can have a <em>metatable</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	263 This <em>metatable</em> 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	264 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	265 under certain special operations.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	266 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	267 of operations over a value by setting specific fields in its metatable.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	268 For instance, when a table is the operand of an addition,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	269 Luan checks for a function in the field "<code>__add</code>" 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	270 If it finds one,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	271 Luan calls this function to perform the addition.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	272
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	273
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	274 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	275 The keys in a metatable are derived from the <em>event</em> names;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	276 the corresponding values are called <ii>metamethods</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	277 In the previous example, the event is <code>"add"</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	278 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	279
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	280
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	281 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	282 You can query the metatable of any table
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	283 using the <a href="#Luan.get_metatable"><code>get_metatable</code></a> function.
371 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 You can replace the metatable of tables
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	288 using the <a href="#Luan.set_metatable"><code>set_metatable</code></a> function.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	289
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	290
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	291 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	292 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	293 arithmetic operations, bitwise operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	294 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	295
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	296
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	297 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	298 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	299 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	300 The key for each event is a string with its name prefixed by
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	301 two underscores, '<code>__</code>';
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	302 for instance, the key for operation "add" is the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	303 string "<code>__add</code>".
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	304 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	305 the access to a metamethod does not invoke other metamethods.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	306 You can emulate how Luan queries a metamethod for an object <code>obj</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	307 with the following code:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	308
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	309 <pre>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	310 raw_get(get_metatable(obj) or {}, "__" .. event_name)
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	311 </pre>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	312
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	313 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	314 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	315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	316 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	317
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	318 <li><p><b>"add": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	319 the <code>+</code> operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	320
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	321 If any operand for an addition is a table,
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	322 Luan will try to call a metamethod.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	323 First, Luan will check the first operand (even if it is valid).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	324 If that operand does not define a metamethod for the "<code>__add</code>" event,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	325 then Luan will check the second operand.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	326 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	327 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	328 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	329 (adjusted to one value)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	330 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	331 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	332 it raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	333 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	334
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	335 <li><p><b>"sub": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	336 the <code>-</code> operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	338 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	339 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	340
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	341 <li><p><b>"mul": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	342 the <code>*</code> operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	344 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	345 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	346
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	347 <li><p><b>"div": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	348 the <code>/</code> operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	350 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	351 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	352
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	353 <li><p><b>"mod": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	354 the <code>%</code> operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	355
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	356 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	357 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	358
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	359 <li><p><b>"pow": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	360 the <code>^</code> (exponentiation) operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	361
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	362 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	363 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	364
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	365 <li><p><b>"unm": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	366 the <code>-</code> (unary minus) operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	367
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	368 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	369 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	370
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	371 <li><p><b>"concat": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	372 the <code>..</code> (concatenation) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	373
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	374 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	375 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	376
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	377 <li><p><b>"len": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	378 the <code>#</code> (length) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	379
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	380 If there is a metamethod,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	381 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	382 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	383 (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	384 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	385 If there is no metamethod but the object is a table,
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	386 then Luan uses the table length operation (see <a href="#length">The Length Operator</a>).
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	387 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	388 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	389
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	390 <li><p><b>"eq": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	391 the <code>==</code> (equal) operation.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	393 Behavior similar to the "add" operation,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	394 except that Luan will try a metamethod only when the values
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	395 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	396 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	397 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	398 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	399
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	400 <li><p><b>"lt": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	401 the <code><</code> (less than) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	402
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	403 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	404 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	405 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	406
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	407 <li><p><b>"le": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	408 the <code><=</code> (less equal) operation.
371 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 Unlike other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	411 The less-equal operation can use two different events.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	412 First, Luan looks for the "<code>__le</code>" 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	413 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	414 If it cannot find such a metamethod,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	415 then it will try the "<code>__lt</code>" event,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	416 assuming that <code>a <= b</code> is equivalent to <code>not (b < a)</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	417 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	418 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	419 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	420
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	421 <li><p><b>"index": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	422 The indexing access <code>table[key]</code>.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	423
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	424 This event happens
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	425 when <code>key</code> is not present in <code>table</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	426 The metamethod is looked up in <code>table</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	427
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	430 Despite the name,
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	431 the metamethod for this event can be any type.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	432 If it is a function,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	433 it is called with <code>table</code> and <code>key</code> as arguments.
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	434 Otherwise
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	435 the final result is the result of indexing this metamethod object with <code>key</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	436 (This indexing is regular, not raw,
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	437 and therefore can trigger another metamethod if the metamethod object is a table.)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	438 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	439
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	440 <li><p><b>"new_index": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	441 The indexing assignment <code>table[key] = value</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	442
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	443 Like the index event,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	444 this event happens when
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	445 when <code>key</code> is not present in <code>table</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	446 The metamethod is looked up in <code>table</code>.
371 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 Like with indexing,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	451 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	452 If it is a function,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	453 it is called with <code>table</code>, <code>key</code>, and <code>value</code> as arguments.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	454 If it is a table,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	455 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	456 (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	457 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	458
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	459
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	460 <p>
428 df95199ca4c0 rename __newindex to __new_index Franklin Schmidt <fschmidt@gmail.com> parents: 418 diff changeset	461 Whenever there is a "new_index" metamethod,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	462 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	463 (If necessary,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	464 the metamethod itself can call <a href="#Luan.raw_set"><code>raw_set</code></a>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	465 to do the assignment.)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	466 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	467
1272 95f6540b27f9 add __gc to docs Franklin Schmidt <fschmidt@gmail.com> parents: 1257 diff changeset	468 <li><p><b>"gc":</b>
95f6540b27f9 add __gc to docs Franklin Schmidt <fschmidt@gmail.com> parents: 1257 diff changeset	469 This is when a table is garbage collected. When the table's <a href="https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#finalize()">finalize</a> method is called by the Java garbage collector, if there is a "<code>__gc</code>" metamethod then it is called with the table as a parameter.
95f6540b27f9 add __gc to docs Franklin Schmidt <fschmidt@gmail.com> parents: 1257 diff changeset	470
95f6540b27f9 add __gc to docs Franklin Schmidt <fschmidt@gmail.com> parents: 1257 diff changeset	471 </li>
95f6540b27f9 add __gc to docs Franklin Schmidt <fschmidt@gmail.com> parents: 1257 diff changeset	472
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	473 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	476
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	477
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	478 <h3 heading><a name="gc" href="#gc">Garbage Collection</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	479
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	480 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	481 Luan uses Java's garbage collection.
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	482
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	483
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	484
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	485
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	486
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	487 <h2 heading><a name="lang" href="#lang">The Language</a></h2>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	488
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	489 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	490 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	491 In other words,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	492 this section describes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	493 which tokens are valid,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	494 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	495 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	496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	497
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	498 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	499 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	500 in which
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	501 {<em>a</em>} means 0 or more <em>a</em>'s, and
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	502 [<em>a</em>] means an optional <em>a</em>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	503 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	504 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	505 and other terminal symbols are shown like ‘<b>=</b>’.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	506 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	507 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	508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	510
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	511 <h3 heading><a name="lex" href="#lex">Lexical Conventions</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	512
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	513 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	514 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	515 between lexical elements (tokens),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	516 except as delimiters between names and keywords.
685 1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	517 Luan considers the end of a line to be the end of a statement. This catches errors and encourages readability. If you want to continue a statement on another line, you can use a backslash followed by a newline which will be treated as white space.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	518
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	519 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	520 <em>Names</em>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	521 (also called <em>identifiers</em>)
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	522 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	523 digits, and underscores,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	524 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	525 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	526
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	528 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	529 The following <em>keywords</em> are reserved
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	530 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	531
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	532
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	533 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	534 and break do else elseif end
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	535 end_do end_for end_function end_if end_while
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	536 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	537 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	538 then true until while
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	539 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	540
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	541 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	542 Luan is a case-sensitive language:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	543 <code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	544 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	548 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	549
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	550 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	551 + - * / % ^ #
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	552 & ~ \| << >> //
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	553 == ~= <= >= < > =
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	554 ( ) { } [ ] ::
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	555 ; : , . .. ...
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	556 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	557
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	558 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	559 <em>Literal strings</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	560 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	561 and can contain the following C-like escape sequences:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	562 '<code>\a</code>' (bell),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	563 '<code>\b</code>' (backspace),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	564 '<code>\f</code>' (form feed),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	565 '<code>\n</code>' (newline),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	566 '<code>\r</code>' (carriage return),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	567 '<code>\t</code>' (horizontal tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	568 '<code>\v</code>' (vertical tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	569 '<code>\\</code>' (backslash),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	570 '<code>\"</code>' (quotation mark [double quote]),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	571 and '<code>\'</code>' (apostrophe [single quote]).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	572 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	573 results in a newline in the string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	574 The escape sequence '<code>\z</code>' 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	575 of white-space characters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	576 including line breaks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	577 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	578 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	579 into the string contents.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	580
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	581
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	582 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	583 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	584 This can be done
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	585 with the escape sequence <code>\x<em>XX</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	586 where <em>XX</em> is a sequence of exactly two hexadecimal digits,
793 60661a8e738c minor Franklin Schmidt <fschmidt@gmail.com> parents: 702 diff changeset	587 or with the escape sequence <code>\u<em>XXXX</em></code>,
60661a8e738c minor Franklin Schmidt <fschmidt@gmail.com> parents: 702 diff changeset	588 where <em>XXXX</em> is a sequence of exactly four hexadecimal digits,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	589 or with the escape sequence <code>\<em>ddd</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	590 where <em>ddd</em> 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	591 (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	592 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	593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	594
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	595 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	596 Literal strings can also be defined using a long format
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	597 enclosed by <em>long brackets</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	598 We define an <em>opening long bracket of level <em>n</em></em> as an opening
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	599 square bracket followed by <em>n</em> 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	600 opening square bracket.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	601 So, an opening long bracket of level 0 is written as <code>[[</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	602 an opening long bracket of level 1 is written as <code>[=[</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	603 and so on.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	604 A <em>closing long bracket</em> is defined similarly;
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	605 for instance,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	606 a closing long bracket of level 4 is written as <code>]====]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	607 A <em>long literal</em> 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	608 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	609 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	610 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	611 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	612 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	613 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	614 (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	615 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	616 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	617
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	618
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	619 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	620 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	621 explicitly affected by the previous rules represents itself.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	622 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	623 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	624 some control characters.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	625 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	626 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	627 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	628
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	629
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	630 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	631 For convenience,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	632 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	633 the newline is not included in the string.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	634 As an example
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	635 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	636
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	637 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	638 a = 'alo\n123"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	639 a = "alo\n123\""
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	640 a = '\97lo\10\04923"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	641 a = [[alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	642 123"]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	643 a = [==[
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	644 alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	645 123"]==]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	646 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	647
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	648 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	649 A <em>numerical constant</em> (or <em>numeral</em>)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	650 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	651 and an optional decimal exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	652 marked by a letter '<code>e</code>' or '<code>E</code>'.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	653 Luan also accepts hexadecimal constants,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	654 which start with <code>0x</code> or <code>0X</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	655 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	656 plus an optional binary exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	657 marked by a letter '<code>p</code>' or '<code>P</code>'.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	658 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	659 denotes a float;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	660 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	661 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	662
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	663 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	664 3 345 0xff 0xBEBADA
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	665 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	666
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	667 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	668 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	669
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	670 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	671 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	672 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	673 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	674
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	675 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	676 A <em>comment</em> starts with a double hyphen (<code>--</code>)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	677 anywhere outside a string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	678 If the text immediately after <code>--</code> is not an opening long bracket,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	679 the comment is a <em>short comment</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	680 which runs until the end of the line.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	681 Otherwise, it is a <em>long comment</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	682 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	683 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	684
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	685
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
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	689 <h3 heading><a name="vars" href="#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	690
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	691 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	692 Variables are places that store values.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	693 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	694 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	695
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	696 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	697 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	698 (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	699 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	700
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	701 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	702 var ::= Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	703 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	704
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	705 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	706 Name denotes identifiers, as defined in <a href="#lex">Lexical Conventions</a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	707
512 d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	708 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	709 Local variables are <em>lexically scoped</em>:
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	710 local variables can be freely accessed by functions
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	711 defined inside their scope (see <a href="#visibility">Visibility Rules</a>).
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	714 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	715 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	716
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	717 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	718 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	719
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	720 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	721 var ::= prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	722 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	723
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	724 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	725 The meaning of accesses to table fields can be changed via metatables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	726 An access to an indexed variable <code>t[i]</code> is equivalent to
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	727 a call <code>gettable_event(t,i)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	728 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	729 <code>gettable_event</code> function.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	730 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	731 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	732
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	733
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	734 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	735 The syntax <code>var.Name</code> is just syntactic sugar for
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	736 <code>var["Name"]</code>:
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	737
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	738 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	739 var ::= prefixexp ‘<b>.</b>’ Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	740 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	741
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	742 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	743 Global variables are not available by default. To enable global variable, you must define <code>_ENV</code> as a local variable whose value is a table. If <code>_ENV</code> is not defined, then an unrecognized variable name will produce a compile error. If <code>_ENV</code> is defined then an access to an unrecognized variable name will be consider a global variable. So then an acces to global variable <code>x</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	744 is equivalent to <code>_ENV.x</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	745 Due to the way that chunks are compiled,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	746 <code>_ENV</code> is never a global name (see <a href="#env">Environments</a>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	747
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	748
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	749
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	750
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	751
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	752 <h3 heading><a name="stmts" href="#stmts">Statements</a></h3>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	753
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	754 <p>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	755 Luan supports an almost conventional set of statements,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	756 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	757 This set includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	758 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	759 and variable declarations.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	762
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	763 <h4 heading><a name="blocks" href="#blocks">Blocks</a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	766 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	767 which are executed sequentially:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	768
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	769 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	770 block ::= {stat}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	771 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	772
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	773 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	774 Luan has <em>empty statements</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	775 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	776 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	777 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	778
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	779 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	780 stat ::= ‘<b>;</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	781 </pre>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	784 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	785
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	786 <pre>
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	787 stat ::= <b>do</b> block end_do
a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	788 end_do ::= <b>end_do</b> \| <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	789 </pre>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	790
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	791 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	792 Explicit blocks are useful
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	793 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	794 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	795 add a <b>return</b> statement in the middle
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	796 of another block (see <a href="#control">Control Structures</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	797
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	798
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	799
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	800
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	801
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	802 <h4 heading><a name="chunks" href="#chunks">Chunks</a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	803
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	804 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	805 The unit of compilation of Luan is called a <em>chunk</em>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	806 Syntactically,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	807 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	808
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	809 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	810 chunk ::= block
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	811 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	812
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	813 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	814 Luan handles a chunk as the body of an anonymous function
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	815 with a variable number of arguments
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	816 (see <a href="#fn_def">Function Definitions</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	817 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	818 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	822 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	823 To execute a chunk,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	824 Luan first <em>loads</em> it,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	825 compiling the chunk's code,
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	826 and then Luan executes the compiled code.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	827
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	828
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	829
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	830
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	831
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	832 <h4 heading><a name="assignment" href="#assignment">Assignment</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	833
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	834 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	835 Luan allows multiple assignments.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	836 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	837 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	838 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	839 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	840
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	841 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	842 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	843 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	844 explist ::= exp {‘<b>,</b>’ exp}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	845 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	846
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	847 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	848 Expressions are discussed in <a href="#expressions">Expressions</a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	849
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	850
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	851 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	852 Before the assignment,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	853 the list of values is <em>adjusted</em> to the length of
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	854 the list of variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	855 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	856 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	857 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	858 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	859 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	860 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	861 before the adjustment
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	862 (except when the call is enclosed in parentheses; see <a href="#expressions">Expressions</a>).
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	865 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	866 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	867 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	868 Thus the code
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	869
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	870 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	871 i = 3
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	872 i, a[i] = i+1, 20
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	873 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	874
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	875 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	876 sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	877 because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	878 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	879 Similarly, the line
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	880
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	881 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	882 x, y = y, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	883 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	884
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	885 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	886 exchanges the values of <code>x</code> and <code>y</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	887 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	888
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	889 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	890 x, y, z = y, z, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	891 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	892
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	893 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	894 cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	895
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	896
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	897 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	898 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	899 and table fields can be changed via metatables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	900 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	901 <code>settable_event(t,i,val)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	902 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	903 <code>settable_event</code> function.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	904 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	905 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	906
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	907
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	908 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	909 An assignment to a global name <code>x = val</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	910 is equivalent to the assignment
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	911 <code>_ENV.x = val</code> (see <a href="#env">Environments</a>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	912 Global names are only available when <code>_ENV</code> is defined.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	913
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	914
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	915
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	916 <h4 heading><a name="control" href="#control">Control Structures</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	917
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	918 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	919 The control structures
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	920 <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	921 familiar syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	922
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	923 <pre>
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	924 stat ::= <b>while</b> exp <b>do</b> block end_while
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	925 stat ::= <b>repeat</b> block <b>until</b> exp
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	926 stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] end_if
a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	927 end_while ::= <b>end_while</b> \| <b>end</b>
a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	928 end_if ::= <b>end_if</b> \| <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	929 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	930
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	931 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	932 Luan also has a <b>for</b> statement (see <a href="#for">For Statement</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	933
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	934
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	935 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	936 The condition expression of a
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	937 control structure must be a boolean.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	938 Any other value type will produce an error.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	939 This helps catch errors and makes code more readable.
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	942 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	943 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	944 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	945 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	946 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	947 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	948
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	949
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	950 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	951 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	952 <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	953 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	954
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	955
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	956 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	957 stat ::= <b>break</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	958 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	959
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	960 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	961 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	962
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	965 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	966 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	967 (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	968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	969 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	970 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	971
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	972 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	973 stat ::= <b>return</b> [explist] [‘<b>;</b>’]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	974 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	975
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	976
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	977
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	978
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	979 <h4 heading><a name="for" href="#for">For Statement</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	980
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	981 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	982 The <b>for</b> statement works over functions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	983 called <em>iterators</em>.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	984 On each iteration, the iterator function is called to produce a new value,
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	985 stopping when this new value is <b>nil</b>.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	986 The <b>for</b> loop has the following syntax:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	987
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	988 <pre>
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	989 stat ::= <b>for</b> namelist <b>in</b> exp <b>do</b> block end_for
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	990 namelist ::= Name {‘<b>,</b>’ Name}
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	991 end_for ::= <b>end_for</b> \| <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	992 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	993
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	994 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	995 A <b>for</b> statement like
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	996
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	997 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	998 for <em>var_1</em>, ···, <em>var_n</em> in <em>exp</em> do <em>block</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	999 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1000
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1001 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1002 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	1003
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1004 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1005 do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1006 local <em>f</em> = <em>exp</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1007 while true do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1008 local <em>var_1</em>, ···, <em>var_n</em> = <em>f</em>()
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1009 if <em>var_1</em> == nil then break end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1010 <em>block</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1011 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1012 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1013 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1014
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1015 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1016 Note the following:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1017
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1018 <ul>
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 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1021 <code><em>exp</em></code> is evaluated only once.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1022 Its result is an <em>iterator</em> function.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1023 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1024
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1025 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1026 <code><em>f</em></code> is an invisible variable.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1027 The name is here for explanatory purposes only.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1028 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1029
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1030 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1031 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	1032 </li>
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 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1035 The loop variables <code><em>var_i</em></code> are local to the loop;
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1036 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	1037 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	1038 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	1039 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1040
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1041 </ul>
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
1520 d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1045 <h4 heading><a name="try" href="#for">Try Statement</a></h4>
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1046
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1047 <p>The <b>try</b> statement has the same semantics as in Java.</p>
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1048
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1049 <pre>
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1050 stat ::= <b>try</b> block [<b>catch</b> Name block] [<b>finally</b> block] end_try
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1051 end_try ::= <b>end_try</b> \| <b>end</b>
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1052 </pre>
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1053
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1054
d9a5405a3102 try statement Franklin Schmidt <fschmidt@gmail.com> parents: 1434 diff changeset	1055
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1056
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1057 <h4 heading><a name="fn_stmt" href="#fn_stmt">Function Calls as Statements</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1058
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1059 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1060 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	1061 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	1062
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1063 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1064 stat ::= functioncall
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1065 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1066
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1067 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1068 In this case, all returned values are thrown away.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1069 Function calls are explained in <a href="#fn_calls">Function Calls</a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1070
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1072
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1073 <h4 heading><a name="local_stmt" href="#local_stmt">Local Declarations</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1074
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1075 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1076 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	1077 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	1078
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1079 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1080 stat ::= <b>local</b> namelist [‘<b>=</b>’ explist]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1081 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1082
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1083 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1084 If present, an initial assignment has the same semantics
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1085 of a multiple assignment (see <a href="#assignment">Assignment</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1086 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	1087
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 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1090 A chunk is also a block (see <a href="#chunks">Chunks</a>),
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1091 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	1092
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 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1095 The visibility rules for local variables are explained in <a href="#visibility">Visibility Rules</a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1096
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1097
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1098 <h4 heading><a name="template_stmt" href="#template_stmt">Template Statements</a></h4>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1099
1384 f5368cd8c056 remove template expressions and String.concat Franklin Schmidt <fschmidt@gmail.com> parents: 1373 diff changeset	1100 <p>Template statements provide the full equivalent of <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a> but in a general way. Template statements write to standard output. For example:</p>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1101
1325 28c1fc6d9d29 website - make docs html Franklin Schmidt <fschmidt@gmail.com> parents: 1324 diff changeset	1102 <pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1103 local name = "Bob"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1104 %>
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1105 Hello <%= name %>!
85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1106 Bye <%= name %>.
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1107 <%
1325 28c1fc6d9d29 website - make docs html Franklin Schmidt <fschmidt@gmail.com> parents: 1324 diff changeset	1108 </pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1109
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1110 <p>is equivalent to the code:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1111
1325 28c1fc6d9d29 website - make docs html Franklin Schmidt <fschmidt@gmail.com> parents: 1324 diff changeset	1112 <pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1113 local name = "Bob"
1384 f5368cd8c056 remove template expressions and String.concat Franklin Schmidt <fschmidt@gmail.com> parents: 1373 diff changeset	1114 require("luan:Io.luan").stdout.write( "Hello ", name , "!\nBye ", name , ".\n" )
1325 28c1fc6d9d29 website - make docs html Franklin Schmidt <fschmidt@gmail.com> parents: 1324 diff changeset	1115 </pre>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1116
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1117
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1118
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1119 <h3 heading><a name="expressions" href="#expressions">Expressions</a></h3>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1120
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1121 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1122 The basic expressions in Luan are the following:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1123
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1124 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1125 exp ::= prefixexp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1126 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	1127 exp ::= Numeral
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1128 exp ::= LiteralString
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1129 exp ::= functiondef
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1130 exp ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1131 exp ::= ‘<b>...</b>’
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1132 exp ::= exp binop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1133 exp ::= unop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1134 prefixexp ::= var \| functioncall \| ‘<b>(</b>’ exp ‘<b>)</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1135 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1136
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1137 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1138 Numerals and literal strings are explained in <a href="#lex">Lexical Conventions</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1139 variables are explained in <a href="#vars">Variables</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1140 function definitions are explained in <a href="#fn_def">Function Definitions</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1141 function calls are explained in <a href="#fn_calls">Function Calls</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1142 table constructors are explained in <a href="#constructors">Table Constructors</a>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1143 Vararg expressions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1144 denoted by three dots ('<code>...</code>'), can only be used when
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1145 directly inside a vararg function;
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1146 they are explained in <a href="#fn_def">Function Definitions</a>.
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1147
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1148
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1149 <p>
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1150 Binary operators comprise arithmetic operators (see <a href="#arithmetic">Arithmetic Operators</a>),
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1151 relational operators (see <a href="#relational">Relational Operators</a>), logical operators (see <a href="#logical_ops">Logical Operators</a>),
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1152 and the concatenation operator (see <a href="#concatenation">Concatenation</a>).
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1153 Unary operators comprise the unary minus (see <a href="#arithmetic">Arithmetic Operators</a>),
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1154 the unary logical <b>not</b> (see <a href="#logical_ops">Logical Operators</a>),
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1155 and the unary <em>length operator</em> (see <a href="#length">The Length Operator</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1157
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1158 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1159 Both function calls and vararg expressions can result in multiple values.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1160 If a function call is used as a statement (see <a href="#fn_stmt">Function Calls as Statements</a>),
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1161 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	1162 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	1163 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	1164 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	1165 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	1166 (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	1167 In all other contexts,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1168 Luan adjusts the result list to one element,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1169 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	1170 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	1171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1172
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1173 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1174 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1175
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1176 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1177 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	1178 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	1179 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	1180 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	1181 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	1182 -- 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	1183 -- 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	1184
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1185 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	1186 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	1187 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	1188 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	1189 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	1190 {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	1191 {...} -- 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	1192 {f(), nil} -- f() is adjusted to 1 result
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1193 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1194
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1195 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1196 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	1197 Thus,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1198 <code>(f(x,y,z))</code> is always a single value,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1199 even if <code>f</code> returns several values.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1200 (The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1201 or <b>nil</b> if <code>f</code> does not return any values.)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1202
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1203
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1204
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1205 <h4 heading><a name="arithmetic" href="#arithmetic">Arithmetic Operators</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1206
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1207 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1208 Luan supports the following arithmetic operators:
371 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 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1211 <li><b><code>+</code>: </b>addition</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1212 <li><b><code>-</code>: </b>subtraction</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1213 <li><b><code>*</code>: </b>multiplication</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1214 <li><b><code>/</code>: </b>division</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1215 <li><b><code>%</code>: </b>modulo</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1216 <li><b><code>^</code>: </b>exponentiation</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1217 <li><b><code>-</code>: </b>unary minus</li>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1218 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1220 <p>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1221 Addition, subtraction, multiplication, division, and unary minus are the same as these operators in Java. Exponentiation uses Java's <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Math.html#pow(double,%20double)">Math.pow</a> function.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1222
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1223 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1224 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	1225 that rounds the quotient towards minus infinite (floor division).
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1226 (The Java modulo operator is not used.)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1227
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1229
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1230 <h4 heading><a name="conversions" href="#conversions">Coercions and Conversions</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1231
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1232 <p>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1233 Luan generally avoids automatic conversions.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1234 String concatenation automatically converts all of its arguments to strings.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1235
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1236 <p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1237 Luan provides library functions for explicit type conversions.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1238
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1239
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1240
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1241
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1242 <h4 heading><a name="relational" href="#relational">Relational Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1243
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1244 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1245 Luan supports the following relational operators:
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1246
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1247 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1248 <li><b><code>==</code>: </b>equality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1249 <li><b><code>~=</code>: </b>inequality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1250 <li><b><code><</code>: </b>less than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1251 <li><b><code>></code>: </b>greater than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1252 <li><b><code><=</code>: </b>less or equal</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1253 <li><b><code>>=</code>: </b>greater or equal</li>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1254 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1255 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	1256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1258 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1259 Equality (<code>==</code>) first compares the type of its operands.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1260 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	1261 Otherwise, the values of the operands are compared.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1262 Strings, numbers, and binary values are compared in the obvious way (by value).
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1263
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1264 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1265 Tables
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1266 are compared by reference:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1267 two objects are considered equal only if they are the same object.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1268 Every time you create a new table,
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1269 it is different from any previously existing table.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1270 Closures are also compared by reference.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1271
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1272 <p>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1273 You can change the way that Luan compares tables
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1274 by using the "eq" metamethod (see <a href="#meta">Metatables and Metamethods</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1275
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1276 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1277 Java values are compared for equality with the Java <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#equals(java.lang.Object)"><code>equals</code></a> method.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1278
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1279 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1280 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	1281 or vice versa.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1282 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1283 and <code>t[0]</code> and <code>t["0"]</code> denote different
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1284 entries in a table.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1285
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1287 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1288 The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1291 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1292 The order operators work as follows.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1293
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1294 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	1295 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	1296 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	1297 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	1298 then their values are compared according to the current locale.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1299 Otherwise, Luan tries to call the "lt" or the "le"
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1300 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1301 A comparison <code>a > b</code> is translated to <code>b < a</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1302 and <code>a >= b</code> is translated to <code>b <= a</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1303
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1304
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1305
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1306
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1307
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1308 <h4 heading><a name="logical_ops" href="#logical_ops">Logical Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1309
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1310 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1311 The logical operators in Luan are
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1312 <b>and</b>, <b>or</b>, and <b>not</b>.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1313 The <b>and</b> and <b>or</b> operators consider both <b>false</b> and <b>nil</b> as false
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1314 and anything else as true.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1315 Like the control structures (see <a href="#control">Control Structures</a>),
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1316 the <b>not</b> operator requires a boolean value.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1317
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1318 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1319 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	1320 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	1321 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	1322 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	1323 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	1324 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	1325 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	1326 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	1327 that is,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1328 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	1329 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1330
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1331 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1332 10 or 20 --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1333 10 or error() --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1334 nil or "a" --> "a"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1335 nil and 10 --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1336 false and error() --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1337 false and nil --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1338 false or nil --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1339 10 and 20 --> 20
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1340 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1341
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1342 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1343 (In this manual,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1344 <code>--></code> indicates the result of the preceding expression.)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1345
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1346
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1347
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1348 <h4 heading><a name="concatenation" href="#concatenation">Concatenation</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1349
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1350 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1351 The string concatenation operator in Luan is
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1352 denoted by two dots ('<code>..</code>').
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1353 All operands are converted to strings.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1354
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1355
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1356
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1357 <h4 heading><a name="length" href="#length">The Length Operator</a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1358
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1359 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1360 The length operator is denoted by the unary prefix operator <code>#</code>.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1361 The length of a string is its number of characters.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1362 The length of a binary is its number of bytes.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1363
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1365 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1366 A program can modify the behavior of the length operator for
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1367 any table through the <code>__len</code> metamethod (see <a href="#meta">Metatables and Metamethods</a>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1368
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1369
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1370 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1371 Unless a <code>__len</code> metamethod is given,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1372 the length of a table <code>t</code> is defined
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1373 as the number of elements in <em>sequence</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1374 that is,
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1375 the size of the set of its positive numeric keys is equal to <em>{1..n}</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1376 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	1377 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	1378 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	1379
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1380 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1381 {10, 20, nil, 40}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1382 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1383
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1384 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1385 has a length of <code>2</code>, because that is the last key in sequence.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1386
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1387
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1388
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1389
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1390
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1391 <h4 heading><a name="precedence" href="#precedence">Precedence</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1392
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1393 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1394 Operator precedence in Luan follows the table below,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1395 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	1396
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1397 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1398 or
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1399 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1400 < > <= >= ~= ==
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 + -
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1403 * / %
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1404 unary operators (not # -)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1405 ^
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1406 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1407
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1408 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1409 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1410 you can use parentheses to change the precedences of an expression.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1411 The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1412 operators are right associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1413 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	1414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1415
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
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1419 <h4 heading><a name="constructors" href="#constructors">Table Constructors</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1420
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1421 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1422 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	1423 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	1424 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	1425 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	1426 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	1427
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1428 <pre>
604 b73f005f3735 table constructor now uses end_of_line as a delimiter Franklin Schmidt <fschmidt@gmail.com> parents: 589 diff changeset	1429 tableconstructor ::= ‘<b>{</b>’ fieldlist ‘<b>}</b>’
b73f005f3735 table constructor now uses end_of_line as a delimiter Franklin Schmidt <fschmidt@gmail.com> parents: 589 diff changeset	1430 fieldlist ::= [field] {fieldsep [field]}
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1431 field ::= ‘<b>[</b>’ exp ‘<b>]</b>’ ‘<b>=</b>’ exp \| Name ‘<b>=</b>’ exp \| exp
604 b73f005f3735 table constructor now uses end_of_line as a delimiter Franklin Schmidt <fschmidt@gmail.com> parents: 589 diff changeset	1432 fieldsep ::= ‘<b>,</b>’ \| ‘<b>;</b>’ \| <b>end_of_line</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1433 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1434
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1435 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1436 Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1437 with key <code>exp1</code> and value <code>exp2</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1438 A field of the form <code>name = exp</code> is equivalent to
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1439 <code>["name"] = exp</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1440 Finally, fields of the form <code>exp</code> are equivalent to
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1441 <code>[i] = exp</code>, where <code>i</code> are consecutive integers
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1442 starting with 1.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1443 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	1444 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1445
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1446 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1447 a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1448 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1449
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1450 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1451 is equivalent to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1452
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1453 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1454 do
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1455 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1456 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1457 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	1458 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	1459 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	1460 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	1461 t[30] = 23
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1462 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	1463 a = t
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1464 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1465 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1466
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1467 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1468 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	1469 (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	1470
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 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1473 If the last field in the list has the form <code>exp</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1474 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	1475 then all values returned by this expression enter the list consecutively
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1476 (see <a href="#fn_calls">Function Calls</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1477
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1479 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1480 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	1481 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	1482
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1486
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1487 <h4 heading><a name="fn_calls" href="#fn_calls">Function Calls</a></h4>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1488
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1489 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1490 A function call in Luan has the following syntax:
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1491
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1492 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1493 functioncall ::= prefixexp args
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1494 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1495
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1496 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1497 In a function call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1498 first prefixexp and args are evaluated.
685 1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	1499 The value of prefixexp must have type <em>function</em>.
1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	1500 This function is called
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1501 with the given arguments.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1502
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1504 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1505 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	1506
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1507 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1508 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	1509 args ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1510 args ::= LiteralString
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1511 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1512
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1513 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1514 All argument expressions are evaluated before the call.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1515 A call of the form <code>f{<em>fields</em>}</code> is
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1516 syntactic sugar for <code>f({<em>fields</em>})</code>;
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1517 that is, the argument list is a single new table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1518 A call of the form <code>f'<em>string</em>'</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1519 (or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1520 is syntactic sugar for <code>f('<em>string</em>')</code>;
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1521 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	1522
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1523
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1524
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1525
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1526 <h4 heading><a name="fn_def" href="#fn_def">Function Definitions</a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1528 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1529 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	1530
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1531 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1532 functiondef ::= <b>function</b> funcbody
1092 a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	1533 funcbody ::= ‘<b>(</b>’ [parlist] ‘<b>)</b>’ block end_function
a26fbde7ee28 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 1090 diff changeset	1534 end_function ::= <b>end_function</b> \| <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1535 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1536
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1537 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1538 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	1539
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1540 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1541 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	1542 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	1543 funcname ::= Name {‘<b>.</b>’ Name} [‘<b>:</b>’ Name]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1544 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1545
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1546 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1547 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1548
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1549 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1550 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1551 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1552
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1553 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1554 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1555
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1556 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1557 f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1558 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1559
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1560 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1561 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1562
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1563 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1564 function t.a.b.c.f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1565 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1566
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1567 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1568 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1569
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1570 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1571 t.a.b.c.f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1572 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1573
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1574 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1575 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1576
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1577 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1578 local function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1579 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1580
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1581 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1582 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1583
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1584 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1585 local f; f = function () <em>body</em> end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1586 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1587
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1588 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1589 not to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1590
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1591 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1592 local f = function () <em>body</em> end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1593 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1594
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1595 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1596 (This only makes a difference when the body of the function
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1597 contains references to <code>f</code>.)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1598
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1599
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1600 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1601 A function definition is an executable expression,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1602 whose value has type <em>function</em>.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1603 When Luan precompiles a chunk,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1604 all its function bodies are precompiled too.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1605 Then, whenever Luan executes the function definition,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1606 the function is <em>instantiated</em> (or <em>closed</em>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1607 This function instance (or <em>closure</em>)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1608 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	1609
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1610
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1611 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1612 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	1613 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	1614
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1615 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1616 parlist ::= namelist [‘<b>,</b>’ ‘<b>...</b>’] \| ‘<b>...</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1617 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1618
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1619 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1620 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	1621 the list of arguments is adjusted to
1090 616761e0b9f6 update documentation for last change Franklin Schmidt <fschmidt@gmail.com> parents: 799 diff changeset	1622 the length of the list of parameters if the list is too short,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1623 unless the function is a <em>vararg function</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1624 which is indicated by three dots ('<code>...</code>')
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1625 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	1626 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	1627 instead, it collects all extra arguments and supplies them
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1628 to the function through a <em>vararg expression</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1629 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	1630 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	1631 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	1632 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	1633 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	1634 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	1635 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	1636 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	1637 (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	1638
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1641 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	1642
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1643 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1644 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	1645 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	1646 function r() return 1,2,3 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1647 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1648
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1649 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1650 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	1651 to the vararg expression:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1652
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1653 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1654 CALL PARAMETERS
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1655
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1656 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	1657 f(3, 4) a=3, b=4
1090 616761e0b9f6 update documentation for last change Franklin Schmidt <fschmidt@gmail.com> parents: 799 diff changeset	1658 f(3, 4, 5) runtime error
616761e0b9f6 update documentation for last change Franklin Schmidt <fschmidt@gmail.com> parents: 799 diff changeset	1659 f(r(), 10) runtime error
616761e0b9f6 update documentation for last change Franklin Schmidt <fschmidt@gmail.com> parents: 799 diff changeset	1660 f(r()) runtime error
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1661
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1662 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	1663 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	1664 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	1665 g(5, r()) a=5, b=1, ... --> 2 3
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1666 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1667
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1668 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1669 Results are returned using the <b>return</b> statement (see <a href="#control">Control Structures</a>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1670 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	1671 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	1672 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	1673
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1674
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1675 <h3 heading><a name="visibility" href="#visibility">Visibility Rules</a></h3>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1676
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1677 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1678 Luan is a lexically scoped language.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1679 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	1680 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	1681 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	1682 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1683
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1684 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1685 x = 10 -- global variable
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1686 do -- new block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1687 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	1688 print(x) --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1689 x = x+1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1690 do -- another block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1691 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	1692 print(x) --> 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1693 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1694 print(x) --> 11
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1695 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1696 print(x) --> 10 (the global one)
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1697 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1698
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1699 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1700 Notice that, in a declaration like <code>local x = x</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1701 the new <code>x</code> being declared is not in scope yet,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1702 and so the second <code>x</code> refers to the outside variable.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1703
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1704
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1705 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1706 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	1707 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	1708 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1709 A local variable used by an inner function is called
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1710 an <em>upvalue</em>, or <em>external local variable</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1711 inside the inner function.
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 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	1716 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1717 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1718
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1719 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1720 a = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1721 local x = 20
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1722 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	1723 local y = 0
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1724 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	1725 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1726 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1727
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1728 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1729 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	1730 (that is, ten instances of the anonymous function).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1731 Each of these closures uses a different <code>y</code> variable,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1732 while all of them share the same <code>x</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1733
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1734
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1735
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1736
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1737
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1738 <h2 heading><a name="libs" href="#libs">Standard Libraries</a></h2>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1739
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1740 <p>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1741 The standard Luan libraries provide useful functions
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1742 that are implemented both in Java and in Luan itself.
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1743 How each function is implemented shouldn't matter to the user.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1744 Some of these functions provide essential services to the language
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1745 (e.g., <a href="#Luan.type"><code>type</code></a> and <a href="#Luan.get_metatable"><code>get_metatable</code></a>);
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1746 others provide access to "outside" services (e.g., I/O).
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1747
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1748
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1749 <h3 heading><a name="default_lib" href="#default_lib">Default Environment</a></h3>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1750
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1751 <p>
1353 8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1752 This is provided by default as a local variable for any Luan code as described in <a href="#env">Environments</a>.
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1753
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1754
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1755 <h4 heading><a name="require" href="#require"><code>require (mod_uri)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1756
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1757 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1758 Example use:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1759
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1760 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1761 local Table = require "luan:Table.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1762 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1763
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1764 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1765 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1766
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1767 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1768 local function require(mod_name)
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1769 return <a href="#Package.load">Package.load</a>(mod_name) or <a href="#Luan.error">Luan.error</a>("module '"..mod_name.."' not found")
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1770 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1771 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1772
1353 8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1773 <p>
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1774 A special case is:
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1775
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1776 <pre>
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1777 require "java"
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1778 </pre>
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1779
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1780 <p>
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1781 This enables Java in the current chunk if that chunk has permission to use Java. If the chunk doesn't have permission to use Java, then an error is thrown.
8d95711f6615 replace java() with require "java" Franklin Schmidt <fschmidt@gmail.com> parents: 1342 diff changeset	1782
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1783
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	1784 <h3 heading><a name="luan_lib" href="#luan_lib">Basic Functions</a></h3>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1785
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1786 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1787 Include this library by:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1788
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1789 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1790 local Luan = require "luan:Luan.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1791 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1792
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1793 <p>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1794 The basic library provides basic functions to Luan that don't depend on other libaries.
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1795
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1796
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1797 <h4 heading><a name="Luan.do_file" href="#Luan.do_file"><code>Luan.do_file ([uri])</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1798
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1799 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1800 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1801
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1802 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1803 function Luan.do_file(uri)
1316 11d3640e739d load_file returns nil for missing file Franklin Schmidt <fschmidt@gmail.com> parents: 1303 diff changeset	1804 local fn = <a href="#Luan.load_file">Luan.load_file</a>(uri) or <a href="#Luan.error">Luan.error</a>("file '"..uri.."' not found")
11d3640e739d load_file returns nil for missing file Franklin Schmidt <fschmidt@gmail.com> parents: 1303 diff changeset	1805 return fn()
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1806 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1807 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1808
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1809
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1810
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1811 <h4 heading><a name="Luan.error" href="#Luan.error"><code>Luan.error (message)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1812
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1813 <p>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1814 Throws an error containing the message.
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1815
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1816 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1817 Could be defined as:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1818
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1819 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1820 function Luan.error(message)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1821 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1822 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1823 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1824
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1825
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1826
1434 56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1827 <h4 heading><a name="Luan.eval" href="#Luan.eval"><code>Luan.eval (text [, source_name [, env]])</code></a></h4>
695 5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1828
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1829 <p>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1830 Evaluates <code>text</code> as a Luan expression.
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1831
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1832 <p>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1833 Could be defined as:
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1834
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1835 <pre>
1395 9dfff82dfc59 finish postgres work Franklin Schmidt <fschmidt@gmail.com> parents: 1389 diff changeset	1836 function Luan.eval(text,source_name, env)
9dfff82dfc59 finish postgres work Franklin Schmidt <fschmidt@gmail.com> parents: 1389 diff changeset	1837 return <a href="#Luan.load">Luan.load</a>( "return "..text, source_name or "eval", env )()
695 5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1838 end
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1839 </pre>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1840
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1841
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1842
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1843 <h4 heading><a name="Luan.get_metatable" href="#Luan.get_metatable"><code>Luan.get_metatable (table)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1844
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1845 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1846 If <code>table</code> does not have a metatable, returns <b>nil</b>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1847 Otherwise,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1848 if the table's metatable has a <code>"__metatable"</code> field,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1849 returns the associated value.
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1850 Otherwise, returns the metatable of the given table.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1851
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1852
1373 372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1853 <h4 heading><a name="Luan.hash_code" href="#Luan.ipairs"><code>Luan.hash_code (v)</code></a></h4>
372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1854
372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1855 <p>
372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1856 Returns the hash code of <code>v</code>.
372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1857
372906d1d08b minor Franklin Schmidt <fschmidt@gmail.com> parents: 1353 diff changeset	1858
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1859 <h4 heading><a name="Luan.ipairs" href="#Luan.ipairs"><code>Luan.ipairs (t)</code></a></h4>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1860
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1861 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1862 Returns an iterator function
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1863 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1864
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1865 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1866 for i,v in ipairs(t) do <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1867 </pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1868
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1869 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1870 will iterate over the key–value pairs
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1871 (<code>1,t[1]</code>), (<code>2,t[2]</code>), ...,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1872 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	1873
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1874 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1875 Could be defined as:
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1876
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1877 <pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1878 function Luan.ipairs(t)
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1879 local i = 0
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1880 return function()
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1881 if i < #t then
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1882 i = i + 1
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1883 return i, t[i]
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1884 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1885 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1886 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1887 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1888
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1889
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1890
1434 56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1891 <h4 heading><a name="Luan.load" href="#Luan.load"><code>Luan.load (text, [source_name [, env [, persist]]])</code></a></h4>
371 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 Loads a chunk.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1895
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1896 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1897 The <code>text</code> is compiled.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1898 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	1899 returns the compiled chunk as a function;
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1900 otherwise, throws an error.
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1901
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1902 <p>
1434 56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1903 The <code>source_name</code> parameter is a string saying where the text came from. It is used to produce error messages. Defaults to "load".
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1904
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1905 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1906 If the <code>env</code> parameter is supplied, it becomes the <code>_ENV</code> of the chunk.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1907
1434 56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1908 <p>
56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1909 The <code>persist</code> parameter is a boolean which determines if the compiled code is persistently cached to a temporary file. Defaults to <code>false</code>.
56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1910
56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1911
56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1912 <h4 heading><a name="Luan.load_file" href="#Luan.load_file"><code>Luan.load_file (file_uri)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1913
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1914 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1915 Similar to <a href="#Luan.load"><code>load</code></a>,
1434 56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1916 but gets the chunk from file <code>file_uri</code>.
56fb5cd8228d cache compiled code in temp files Franklin Schmidt <fschmidt@gmail.com> parents: 1422 diff changeset	1917 <code>file_uri</code> can be a string or a uri table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1918
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1919
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1920 <h4 heading><a name="Luan.new_error" href="#Luan.new_error"><code>Luan.new_error (message)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1921
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1922 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1923 Creates a new error table containing the message assigned to "<code>message</code>". The error table also contains a <code>throw</code> function which throws the error. The table also contains a list of stack trace elements where each stack trace element is a table containing "<code>source</code>", "<code>line</code>", and possible "<code>call_to</code>". The table also has a metatable containing "<code>__to_string</code>" to render the error.
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1924
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1925 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1926 To print the current stack trace, you could do:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1927
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1928 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1929 Io.print( Luan.new_error "stack" )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1930 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1931
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1932
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1933 <h4 heading><a name="Luan.pairs" href="#Luan.pairs"><code>Luan.pairs (t)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1934
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1935 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1936 If <code>t</code> has a metamethod <code>__pairs</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1937 calls it with <code>t</code> as argument and returns the
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	1938 result from the call.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1941 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1942 Otherwise,
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	1943 returns a function
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1944 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1945
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1946 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1947 for k,v in pairs(t) do <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1948 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1949
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1950 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1951 will iterate over all key–value pairs of table <code>t</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1952
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1953
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1954
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1955 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1956 <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	1957 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	1958 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	1959 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	1960 <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	1961 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	1962 for instance for debugging.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1963 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	1964 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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1968 <h4 heading><a name="Luan.range" href="#Luan.range"><code>Luan.range (start, stop [, step])</code></a></h4>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1969
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1970 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1971 Based on <a href="https://docs.python.org/2/library/functions.html#range">the Python range() function</a>, this lets one iterate through a sequence of numbers.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1972
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1973 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1974 Example use:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1975
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1976 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1977 for i in range(1,10) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1978 Io.print("count up:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1979 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1980 for i in range(10,0,-1) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1981 Io.print("count down:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1982 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1983 </pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1984
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1985 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1986 Could be defined as:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1987
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1988 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1989 function Luan.range(start, stop, step)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1990 step = step or 1
478 eb6d90fb0b5c documentation Franklin Schmidt <fschmidt@gmail.com> parents: 476 diff changeset	1991 step == 0 and <a href="#Luan.error">Luan.error</a> "bad argument #3 (step may not be zero)"
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1992 local i = start
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1993 return function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1994 if step > 0 and i <= stop or step < 0 and i >= stop then
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1995 local rtn = i
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1996 i = i + step
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1997 return rtn
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1998 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1999 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2000 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2001 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2002
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2003
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2004
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2005 <h4 heading><a name="Luan.raw_equal" href="#Luan.raw_equal"><code>Luan.raw_equal (v1, v2)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2006
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2007 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2008 Checks whether <code>v1</code> is equal to <code>v2</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2009 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2010 Returns a boolean.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2011
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2013
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2014 <h4 heading><a name="Luan.raw_get" href="#Luan.raw_get"><code>Luan.raw_get (table, index)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2015
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2016 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2017 Gets the real value of <code>table[index]</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2018 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2019 <code>table</code> must be a table;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2020 <code>index</code> may be any value.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2021
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2022
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2023
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2024 <h4 heading><a name="Luan.raw_len" href="#Luan.raw_len"><code>Luan.raw_len (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2025
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2026 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2027 Returns the length of the object <code>v</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2028 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	2029 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2030 Returns an integer.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2031
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2034 <h4 heading><a name="Luan.raw_set" href="#Luan.raw_set"><code>Luan.raw_set (table, index, value)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2035
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2036 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2037 Sets the real value of <code>table[index]</code> to <code>value</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2038 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2039 <code>table</code> must be a table,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2040 <code>index</code> any value different from <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2041 and <code>value</code> any Lua value.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2042
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2043
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2044 <h4 heading><a name="Luan.set_metatable" href="#Luan.set_metatable"><code>Luan.set_metatable (table, metatable)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2045
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2046 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2047 Sets the metatable for the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2048 If <code>metatable</code> is <b>nil</b>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2049 removes the metatable of the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2050 If the original metatable has a <code>"__metatable"</code> field,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2051 raises an error.
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
1389 eb8b35dccd99 cleanup and stringify change Franklin Schmidt <fschmidt@gmail.com> parents: 1384 diff changeset	2054 <h4 heading><a name="Luan.stringify" href="#Luan.stringify"><code>Luan.stringify (v [,options])</code></a></h4>
eb8b35dccd99 cleanup and stringify change Franklin Schmidt <fschmidt@gmail.com> parents: 1384 diff changeset	2055
eb8b35dccd99 cleanup and stringify change Franklin Schmidt <fschmidt@gmail.com> parents: 1384 diff changeset	2056 <p>
eb8b35dccd99 cleanup and stringify change Franklin Schmidt <fschmidt@gmail.com> parents: 1384 diff changeset	2057 Receives a value of any type and converts it to a string that is a Luan expression. <code>options</code> is a table. If <code>options.strict==true</code> then invalid types throw an error. Otherwise invalid types are represented but the resulting expression is invalid. If <code>options.number_types==true</code> then numbers will be wrapped in functions for their type.
1189 73d754b1889f add stringify Franklin Schmidt <fschmidt@gmail.com> parents: 1164 diff changeset	2058
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2059
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2060 <h4 heading><a name="Luan.to_string" href="#Luan.to_string"><code>Luan.to_string (v)</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2061
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2062 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2063 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	2064 converts it to a string in a human-readable format.
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2065
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2066 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2067 If the metatable of <code>v</code> has a <code>"__to_string"</code> field,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2068 then <code>to_string</code> calls the corresponding value
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2069 with <code>v</code> as argument,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2070 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	2071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2073
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2074 <h4 heading><a name="Luan.type" href="#Luan.type"><code>Luan.type (v)</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2075
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2076 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2077 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	2078 The possible results of this function are
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2079 "<code>nil</code>" (a string, not the value <b>nil</b>),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2080 "<code>number</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2081 "<code>string</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2082 "<code>binary</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2083 "<code>boolean</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2084 "<code>table</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2085 "<code>function</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2086 and "<code>java</code>".
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2087
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2088
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2089 <h4 heading><a name="Luan.values" href="#Luan.values"><code>Luan.values (···)</code></a></h4>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2090
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2091 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2092 Returns a function so that the construction
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2093
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2094 <pre>
1276 623dfe0e2e73 change Luan.values Franklin Schmidt <fschmidt@gmail.com> parents: 1272 diff changeset	2095 for i, v in Luan.values(···) do <em>body</em> end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2096 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2097
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2098 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2099 will iterate over all values of <code>···</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2100
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2101
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2102
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2103 <h4 heading><a name="Luan.VERSION" href="#Luan.VERSION"><code>Luan.VERSION</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2104
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2105 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2106 A global variable (not a function) that
1325 28c1fc6d9d29 website - make docs html Franklin Schmidt <fschmidt@gmail.com> parents: 1324 diff changeset	2107 holds a string containing the current Luan version.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2108
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2109
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2110
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2111
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2112
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2113
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2114 <h3 heading><a name="package_lib" href="#package_lib">Modules</a></h3>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2115
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2116 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2117 Include this library by:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2118
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2119 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2120 local Package = require "luan:Package.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2121 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2123 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2124 The package library provides basic
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2125 facilities for loading modules in Luan.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2126
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2127
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2128 <h4 heading><a name="Package.load" href="#Package.load"><code>Package.load (mod_uri)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2129
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2130 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2131 Loads the given module.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2132 The function starts by looking into the <a href="#Package.loaded"><code>Package.loaded</code></a> table
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2133 to determine whether <code>mod_uri</code> is already loaded.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2134 If it is, then <code>Package.load</code> returns the value stored
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2135 at <code>Package.loaded[mod_uri]</code>.
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2136 Otherwise, it tries to load a new value for the module.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2137
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2138 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2139 To load a new value, <code>Package.load</code> first checks if <code>mod_uri</code> starts with "<b>java:</b>". If yes, then this is a Java class which is loaded by special Java code.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2140
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2141 <p>
799 9c13a15a4002 Package.load() now returns false instead of null, and caches the result. This cleans up the luan.isLocked issues. Franklin Schmidt <fschmidt@gmail.com> parents: 793 diff changeset	2142 Otherwise <code>Package.load</code> tries to read the text of the file referred to by <code>mod_uri</code>. If the file doesn't exist, then <code>Package.load</code> returns <b>false</b>. If the file exists, then its content is compiled into a chunk by calling <a href="#Luan.load"><code>Luan.load</code></a>. This chunk is run passing in <code>mod_uri</code> as an argument. The value returned by the chunk must not be <b>nil</b> and is loaded.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2143
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2144 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2145 If a new value for the module successful loaded, then it is stored in <code>Package.loaded[mod_uri]</code>. The value is returned.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2146
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2147
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2148
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2149
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2150 <h4 heading><a name="Package.loaded" href="#Package.loaded"><code>Package.loaded</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2151
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2152
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2153 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2154 A table used by <a href="#Package.load"><code>Package.load</code></a> to control which
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2155 modules are already loaded.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2156 When you load a module <code>mod_uri</code> and
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2157 <code>Package.loaded[mod_uri]</code> is not <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2158 <a href="#Package.load"><code>Package.load</code></a> simply returns the value stored there.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2160
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2161 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2162 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	2163 assignments to this variable do not change the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2164 table used by <a href="#Package.load"><code>Package.load</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2165
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2166
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2167
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2168
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2169
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2170
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2171 <h3 heading><a name="string_lib" href="#string_lib">String Manipulation</a></h3>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2172
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2173 <p>
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2174 Include this library by:
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2175
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2176 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2177 local String = require "luan:String.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2178 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2179
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2180 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2181 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	2182 such as finding and extracting substrings, and pattern matching.
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2183 When indexing a string in Luan, the first character is at position 1
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2184 (not at 0, as in Java).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2185 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	2186 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	2187 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	2188
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2190
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2191 <h4 heading><a name="String.char" href="#String.char"><code>String.char (···)</code></a></h4>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2192
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2193 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2194 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	2195 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	2196 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	2197 to its corresponding argument.
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2200 <h4 heading><a name="String.encode" href="#String.encode"><code>String.encode (s)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2201
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2202 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2203 Encodes argument <code>s</code> into a string that can be placed in quotes so as to return the original value of the string.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2204
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2205
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2206
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2207
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2208 <h4 heading><a name="String.find" href="#String.find"><code>String.find (s, pattern [, init [, plain]])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2209
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2210 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2211 Looks for the first match of
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2212 <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) in the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2213 If it finds a match, then <code>find</code> returns the indices of <code>s</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2214 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	2215 otherwise, it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2216 A third, optional numerical argument <code>init</code> specifies
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2217 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	2218 its default value is 1 and can be negative.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2219 A value of <b>true</b> as a fourth, optional argument <code>plain</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2220 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	2221 so the function does a plain "find substring" operation,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2222 with no characters in <code>pattern</code> being considered magic.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2223 Note that if <code>plain</code> is given, then <code>init</code> must be given as well.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2224
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2225 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2226 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	2227 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	2228 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	2229 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2230
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2231
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2232
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2233
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2234 <h4 heading><a name="String.format" href="#String.format"><code>String.format (formatstring, ···)</code></a></h4>
371 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 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	2239 following the description given in its first argument (which must be a string).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2240 The format string follows the same rules as the Java function <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#format(java.lang.String,%20java.lang.Object...)"><code>String.format</code></a> because Luan calls this internally.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2241
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2242 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2243 Note that Java's <code>String.format</code> is too stupid to convert between ints and floats, so you must provide the right kind of number.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2244
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2245
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2246
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2247 <h4 heading><a name="String.gmatch" href="#String.gmatch"><code>String.gmatch (s, pattern)</code></a></h4>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2248
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2249 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2250 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	2251 each time it is called,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2252 returns the next captures from <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2253 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2254 If <code>pattern</code> specifies no captures,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2255 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	2256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2258 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2259 As an example, the following loop
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2260 will iterate over all the words from string <code>s</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2261 printing one per line:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2262
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2263 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2264 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2265 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2266 print(w)
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2267 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2268 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2269
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2270 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2271 The next example collects all pairs <code>key=value</code> from the
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2272 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	2273
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2274 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2275 local t = {}
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2276 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2277 for k, v in String.gmatch(s, [[(\w+)=(\w+)]]) do
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2278 t[k] = v
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2279 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2280 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2281
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2282 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2283 For this function, a caret '<code>^</code>' at the start of a pattern does not
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2284 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	2285
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2287
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2288 <h4 heading><a name="String.gsub" href="#String.gsub"><code>String.gsub (s, pattern, repl [, n])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2289
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2290 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2291 Returns a copy of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2292 in which all (or the first <code>n</code>, if given)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2293 occurrences of the <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) have been
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2294 replaced by a replacement string specified by <code>repl</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2295 which can be a string, a table, or a function.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2296 <code>gsub</code> also returns, as its second value,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2297 the total number of matches that occurred.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2298 The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2299
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2300
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2301 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2302 If <code>repl</code> is a string, then its value is used for replacement.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2303 The character <code>\</code> works as an escape character.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2304 Any sequence in <code>repl</code> of the form <code>$<em>d</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2305 with <em>d</em> between 1 and 9,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2306 stands for the value of the <em>d</em>-th captured substring.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2307 The sequence <code>$0</code> stands for the whole match.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2308
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2309
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2310 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2311 If <code>repl</code> is a table, then the table is queried for every match,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2312 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	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>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2316 If <code>repl</code> is a function, then this function is called every time a
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2317 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	2318 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2319
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2321 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2322 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2323 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	2324 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	2325
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2326
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2327 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2328 If the value returned by the table query or by the function call
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2329 is not <b>nil</b>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2330 then it is used as the replacement string;
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2331 otherwise, if it is <b>nil</b>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2332 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	2333 (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	2334
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2335
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2336 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2337 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2338
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2339 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2340 x = String.gsub("hello world", [[(\w+)]], "$1 $1")
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2341 --> 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	2342
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2343 x = String.gsub("hello world", [[\w+]], "$0 $0", 1)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2344 --> x="hello hello world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2345
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2346 x = String.gsub("hello world from Luan", [[(\w+)\s*(\w+)]], "$2 $1")
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2347 --> x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2348
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2349 x = String.gsub("4+5 = $return 4+5$", [[\$(.*?)\$]], function (s)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2350 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2351 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2352 --> x="4+5 = 9"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2354 local t = {name="lua", version="5.3"}
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2355 x = String.gsub("$name-$version.tar.gz", [[\$(\w+)]], t)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2356 --> x="lua-5.3.tar.gz"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2357 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2358
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2359
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2360 <h4 heading><a name="String.lower" href="#String.lower"><code>String.lower (s)</code></a></h4>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2361 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2362 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	2363 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	2364 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	2365
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2366
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2367
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2368 <h4 heading><a name="String.match" href="#String.match"><code>String.match (s, pattern [, init])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2369
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2370 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2371 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2372 <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) in the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2373 If it finds one, then <code>match</code> returns
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2374 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	2375 otherwise it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2376 If <code>pattern</code> specifies no captures,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2377 then the whole match is returned.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2378 A third, optional numerical argument <code>init</code> specifies
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2379 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	2380 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	2381
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2382
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2383 <h4 heading><a name="String.matches" href="#String.matches"><code>String.matches (s, pattern)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2384 <p>
629 35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2385 Returns a boolean indicating whether the <code>pattern</code> can be found in string <code>s</code>.
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2386 This function is equivalent to
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2387
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2388 <pre>
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2389 return String.match(s,pattern) ~= nil
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2390 </pre>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2391
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2392
1422 e48290f3d9fb better quoting Franklin Schmidt <fschmidt@gmail.com> parents: 1395 diff changeset	2393 <h4 heading><a name="String.regex_quote" href="#String.regex_quote"><code>String.regex_quote (s)</code></a></h4>
e48290f3d9fb better quoting Franklin Schmidt <fschmidt@gmail.com> parents: 1395 diff changeset	2394 <p>
e48290f3d9fb better quoting Franklin Schmidt <fschmidt@gmail.com> parents: 1395 diff changeset	2395 Returns a string which matches the literal string <code>s</code> in a regular expression. This function is simply the Java method <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html#quote(java.lang.String)"><code>Pattern.quote</code></a>.
e48290f3d9fb better quoting Franklin Schmidt <fschmidt@gmail.com> parents: 1395 diff changeset	2396
e48290f3d9fb better quoting Franklin Schmidt <fschmidt@gmail.com> parents: 1395 diff changeset	2397
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2398 <h4 heading><a name="String.rep" href="#String.rep"><code>String.rep (s, n [, sep])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2399 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2400 Returns a string that is the concatenation of <code>n</code> copies of
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2401 the string <code>s</code> separated by the string <code>sep</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2402 The default value for <code>sep</code> is the empty string
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2403 (that is, no separator).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2404 Returns the empty string if <code>n</code> is not positive.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2405
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2406
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2407
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2408
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2409 <h4 heading><a name="String.reverse" href="#String.reverse"><code>String.reverse (s)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2410 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2411 Returns a string that is the string <code>s</code> reversed.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2412
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2413
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2414
1195 9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2415 <h4 heading><a name="String.split" href="#String.match"><code>String.split (s, pattern [, limit])</code></a></h4>
9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2416
9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2417 <p>
9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2418 Splits <code>s</code> using regex <code>pattern</code> and returns the results. If <code>limit</code> is positive, then only returns at most that many results. If <code>limit</code> is zero, then remove trailing empty results.
9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2419
9a57f0b16c2b better String.split Franklin Schmidt <fschmidt@gmail.com> parents: 1189 diff changeset	2420
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2421
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2422 <h4 heading><a name="String.sub" href="#String.sub"><code>String.sub (s, i [, j])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2423
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2424 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2425 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2426 starts at <code>i</code> and continues until <code>j</code>;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2427 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2428 If <code>j</code> is absent, then it is assumed to be equal to -1
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2429 (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	2430 In particular,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2431 the call <code>string.sub(s,1,j)</code> returns a prefix of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2432 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2433 and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2434 with length <code>i</code>.
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2437 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2438 If, after the translation of negative indices,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2439 <code>i</code> is less than 1,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2440 it is corrected to 1.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2441 If <code>j</code> is greater than the string length,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2442 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	2443 If, after these corrections,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2444 <code>i</code> is greater than <code>j</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2445 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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2449 <h4 heading><a name="String.to_binary" href="#String.to_binary"><code>String.to_binary (s)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2450
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2451 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2452 Converts a string to a binary by calling the Java method <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#getBytes()"><code>String.getBytes</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2453
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2454
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2455
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2456 <h4 heading><a name="String.to_number" href="#String.to_number"><code>String.to_number (s [, base])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2457
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2458 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2459 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2460 <code>to_number</code> tries to convert its argument to a number.
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2461 If the argument is
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2462 a string convertible to a number,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2463 then <code>to_number</code> returns this number;
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2464 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2465
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2466 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2467
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2468
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2469 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2470 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2471 then <code>s</code> must be a string to be interpreted as
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2472 an integer numeral in that base.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2473 In bases above 10, the letter '<code>A</code>' (in either upper or lower case)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2474 represents 10, '<code>B</code>' represents 11, and so forth,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2475 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2476 If the string <code>s</code> is not a valid numeral in the given base,
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2477 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2478
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2479
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2480
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2481 <h4 heading><a name="String.trim" href="#String.trim"><code>String.trim (s)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2482
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2483 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2484 Removes the leading and trailing whitespace by calling the Java method <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#trim()"><code>String.trim</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2485
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2486
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2487
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2488
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2489 <h4 heading><a name="String.unicode" href="#String.unicode"><code>String.unicode (s [, i [, j]])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2490
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2491 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2492 Returns the internal numerical codes of the characters <code>s[i]</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2493 <code>s[i+1]</code>, ..., <code>s[j]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2494 The default value for <code>i</code> is 1;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2495 the default value for <code>j</code> is <code>i</code>.
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2496 These indices are corrected
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2497 following the same rules of function <a href="#String.sub"><code>String.sub</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2498
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2499
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2500
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2501
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2502
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2503 <h4 heading><a name="String.upper" href="#String.upper"><code>String.upper (s)</code></a></h4>
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2504 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2505 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	2506 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	2507 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	2508 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	2509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2511
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2512
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2513
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2514 <h3 heading><a name="binary_lib" href="#binary_lib">Binary Manipulation</a></h3>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2515
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2516 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2517 Include this library by:
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2518
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2519 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2520 local Binary = require "luan:Binary.luan"
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2521 </pre>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2522
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2523
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2524 <h4 heading><a name="Binary.binary" href="#Binary.binary"><code>Binary.binary (···)</code></a></h4>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2525
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2526 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2527 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2528 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2529 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2530 to its corresponding argument.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2531
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2532
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2533 <h4 heading><a name="Binary.byte" href="#Binary.byte"><code>Binary.byte (b [, i [, j]])</code></a></h4>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2534
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2535 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2536 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2537 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2538 The default value for <code>i</code> is 1;
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2539 the default value for <code>j</code> is <code>i</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2540 These indices are corrected
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2541 following the same rules of function <a href="#String.sub"><code>String.sub</code></a>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2542
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2543
1257 e38f5869e9df don't reset in send_redirect and other improvements Franklin Schmidt <fschmidt@gmail.com> parents: 1216 diff changeset	2544 <h4 heading><a name="Binary.to_string" href="#Binary.to_string"><code>Binary.to_string (b [,charset])</code></a></h4>
e38f5869e9df don't reset in send_redirect and other improvements Franklin Schmidt <fschmidt@gmail.com> parents: 1216 diff changeset	2545 <p>
e38f5869e9df don't reset in send_redirect and other improvements Franklin Schmidt <fschmidt@gmail.com> parents: 1216 diff changeset	2546 If <code>charset</code> is not nil then converts the binary <code>b</code> to a string using the Java <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#String(byte[],%20java.lang.String)">String constructor</a>, else makes each byte a char.
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2547
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2550
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2551 <h3 heading><a name="table_lib" href="#table_lib">Table Manipulation</a></h3>
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2552
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2553 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2554 Include this library by:
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2555
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2556 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2557 local Table = require "luan:Table.luan"
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2558 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2559
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2560 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2561 This library provides generic functions for table manipulation.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2562 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2563
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2564
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2565
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2566 <h4 heading><a name="Table.clear" href="#Table.clear"><code>Table.clear (tbl)</code></a></h4>
580 1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2567
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2568 <p>
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2569 Clears the table.
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2570
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2571
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2572 <h4 heading><a name="Table.concat" href="#Table.concat"><code>Table.concat (list [, sep [, i [, j]]])</code></a></h4>
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2573
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2574 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2575 Given a list,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2576 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	2577 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	2578 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	2579 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	2580 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	2581
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2582
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2583 <h4 heading><a name="Table.copy" href="#Table.copy"><code>Table.copy (tbl [, i [, j]])</code></a></h4>
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2584
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2585 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2586 If <code>i</code> is <code>nil</code>, returns a shallow copy of <code>tbl</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2587 Otherwise returns a new table which is a list of the elements <code>tbl[i] ··· tbl[j]</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2588 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2589
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2590
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2591
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2592 <h4 heading><a name="Table.insert" href="#Table.insert"><code>Table.insert (list, pos, value)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2594 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2595 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	2596 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2597 <code>list[pos], list[pos+1], ···, list[#list]</code>.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2598
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2599
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2600
1100 ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2601 <h4 heading><a name="Table.is_empty" href="#Table.is_empty"><code>Table.is_empty (tbl)</code></a></h4>
ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2602
ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2603
ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2604
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2605 <h4 heading><a name="Table.pack" href="#Table.pack"><code>Table.pack (···)</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2608 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	2609 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	2610 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2614
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2615 <h4 heading><a name="Table.remove" href="#Table.remove"><code>Table.remove (list, pos)</code></a></h4>
371 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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2618 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2619 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	2620 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	2621 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	2622 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	2623 <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	2624 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	2625 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	2626 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	2627 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	2628
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2629
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2630
1100 ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2631 <h4 heading><a name="Table.size" href="#Table.size"><code>Table.size (tbl)</code></a></h4>
ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2632
ad6b3b9fef40 add Table.is_empty() and Table.size() Franklin Schmidt <fschmidt@gmail.com> parents: 1092 diff changeset	2633
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2634
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2635 <h4 heading><a name="Table.sort" href="#Table.sort"><code>Table.sort (list [, comp])</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2638 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	2639 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	2640 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	2641 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	2642 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	2643 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	2644 (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	2645 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	2646 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	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 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	2650 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	2651 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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2655 <h4 heading><a name="Table.unpack" href="#Table.unpack"><code>Table.unpack (list [, i [, j]])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2656
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2657 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2658 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	2659 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	2660
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2661 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2662 return list[i], list[i+1], ···, list[j]
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2663 </pre>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2664
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2665 <p>
1277 5ba660381bd5 fix Io.print() Franklin Schmidt <fschmidt@gmail.com> parents: 1276 diff changeset	2666 By default, <code>i</code> is 1 and <code>j</code> is <code>list.n or #list</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2667
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2668
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2669
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2670
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2671 <h3 heading><a name="number_lib" href="#number_lib">Number Manipulation</a></h3>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2672
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2673 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2674 Include this library by:
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2675
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2676 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2677 local Number = require "luan:Number.luan"
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2678 </pre>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2679
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2680
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2681 <h4 heading><a name="Number.double" href="#Number.double"><code>Number.double (x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2682 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2683 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2684
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2685
1342 60599adc27b8 add lucene search options Franklin Schmidt <fschmidt@gmail.com> parents: 1327 diff changeset	2686 <h4 heading><a name="Number.float" href="#Number.double"><code>Number.float (x)</code></a></h4>
60599adc27b8 add lucene search options Franklin Schmidt <fschmidt@gmail.com> parents: 1327 diff changeset	2687 <p>
60599adc27b8 add lucene search options Franklin Schmidt <fschmidt@gmail.com> parents: 1327 diff changeset	2688 Returns <code>x</code> as a float.
60599adc27b8 add lucene search options Franklin Schmidt <fschmidt@gmail.com> parents: 1327 diff changeset	2689
60599adc27b8 add lucene search options Franklin Schmidt <fschmidt@gmail.com> parents: 1327 diff changeset	2690
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2691 <h4 heading><a name="Number.integer" href="#Number.integer"><code>Number.integer (x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2692 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2693 If the value <code>x</code> is convertible to an integer,
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2694 returns that integer.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2695 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2696
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2697
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2698 <h4 heading><a name="Number.long" href="#Number.long"><code>Number.long (x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2699 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2700 If the value <code>x</code> is convertible to an long,
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2701 returns that long.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2702 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2703
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2704
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2705 <h4 heading><a name="Number.long_to_string" href="#Number.long_to_string"><code>Number.long_to_string (i, radix)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2706 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2707 Converts long value <code>i</code> to a string by calling <code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Long.html#toString(long,%20int)">Long.toString</a></code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2708
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2709
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2710 <h4 heading><a name="Number.type" href="#Number.type"><code>Number.type (x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2711 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2712 Returns a string for the numeric type of <code>x</code>. Possible return values include "<code>integer</code>", "<code>long</code>", "<code>double</code>", and "<code>float</code>".
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2713
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2714
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2715
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2716
1327 b29eefad2111 website - improve docs Franklin Schmidt <fschmidt@gmail.com> parents: 1326 diff changeset	2717 <h3 heading><a name="math_lib" href="#math_lib">Mathematical Functions</a></h3>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2718
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2719 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2720 Include this library by:
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2721
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2722 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2723 local Math = require "luan:Math.luan"
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2724 </pre>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2727 This library provides basic mathematical functions.
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2728 It provides all its functions and constants inside the table <code>Math</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2729
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2730
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2731 <h4 heading><a name="Math.abs" href="#Math.abs"><code>Math.abs (x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2732
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2733 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2734 Returns the absolute value of <code>x</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2735
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2736
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2737
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2738 <h4 heading><a name="Math.acos" href="#Math.acos"><code>Math.acos (x)</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2741 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2745
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2746 <h4 heading><a name="Math.asin" href="#Math.asin"><code>Math.asin (x)</code></a></h4>
371 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 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	2750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2751
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2752
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2753
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2754 <h4 heading><a name="Math.atan" href="#Math.atan"><code>Math.atan (y, x)</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2755
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2756 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2757 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	2758 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	2759 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2760 (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	2761
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2762
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2763
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2764
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2765 <h4 heading><a name="Math.ceil" href="#Math.ceil"><code>Math.ceil (x)</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2768 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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2773 <h4 heading><a name="Math.cos" href="#Math.cos"><code>Math.cos (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2774
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2775 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2776 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	2777
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2778
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2779
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2780
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2781 <h4 heading><a name="Math.deg" href="#Math.deg"><code>Math.deg (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2782
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2783 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2784 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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2789 <h4 heading><a name="Math.exp" href="#Math.exp"><code>Math.exp (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2790
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2791 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2792 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	2793 (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	2794
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2795
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2796
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2797
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2798 <h4 heading><a name="Math.floor" href="#Math.floor"><code>Math.floor (x)</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2801 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	2802
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2804
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2805
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2806 <h4 heading><a name="Math.fmod" href="#Math.fmod"><code>Math.fmod (x, y)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2807
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2808 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2809 Returns the remainder of the division of <code>x</code> by <code>y</code>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2810 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2811
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2812
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2813
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2814
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2815 <h4 heading><a name="Math.huge" href="#Math.huge"><code>Math.huge</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2816
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2817 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2818 A value larger than any other numerical value.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2819
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2820
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2821
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2822
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2823 <h4 heading><a name="Math.log" href="#Math.log"><code>Math.log (x [, base])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2824
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2825 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2826 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	2827 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	2828 (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	2829
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2830
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2831
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2832
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2833 <h4 heading><a name="Math.max" href="#Math.max"><code>Math.max (x, ···)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2834
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2835 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2836 Returns the argument with the maximum value,
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2837 according to the Lua operator <code><</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2838
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2839
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2840
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2841
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2842 <h4 heading><a name="Math.max_integer" href="#Math.max_integer"><code>Math.max_integer</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2843 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2844 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2848
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2849 <h4 heading><a name="Math.min" href="#Math.min"><code>Math.min (x, ···)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2850
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2851 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2852 Returns the argument with the minimum value,
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2853 according to the Lua operator <code><</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2854
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2855
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2856
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2857
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2858 <h4 heading><a name="Math.min_integer" href="#Math.min_integer"><code>Math.min_integer</code></a></h4>
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2859 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2860 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	2861
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2862
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2865 <h4 heading><a name="Math.modf" href="#Math.modf"><code>Math.modf (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2866
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2867 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2868 Returns the integral part of <code>x</code> and the fractional part of <code>x</code>.
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2869
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2870
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2871
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2872
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2873 <h4 heading><a name="Math.pi" href="#Math.pi"><code>Math.pi</code></a></h4>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2876 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	2877
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2880
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2881 <h4 heading><a name="Math.rad" href="#Math.rad"><code>Math.rad (x)</code></a></h4>
371 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 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	2885
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2888
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2889 <h4 heading><a name="Math.random" href="#Math.random"><code>Math.random ([m [, n])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2890
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2891
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2892 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2893 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2894 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	2895 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	2896 When called with two integers <code>m</code> and <code>n</code>,
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2897 <code>Math.random</code> returns a pseudo-random integer
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2898 with uniform distribution in the range <em>[m, n]</em>.
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2899 (The value <em>m-n</em> cannot be negative and must fit in a Luan integer.)
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2900 The call <code>Math.random(n)</code> is equivalent to <code>Math.random(1,n)</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2901
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2902
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2903 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2904 This function is an interface to the underling
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2905 pseudo-random generator function provided by Java.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2906 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	2907
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2908
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2911 <h4 heading><a name="Math.sin" href="#Math.sin"><code>Math.sin (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2913 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2914 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	2915
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2916
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2917
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2918
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2919 <h4 heading><a name="Math.sqrt" href="#Math.sqrt"><code>Math.sqrt (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2920
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2921 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2922 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	2923 (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	2924
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2927
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2928 <h4 heading><a name="Math.tan" href="#Math.tan"><code>Math.tan (x)</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2929
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2930 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2931 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	2932
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2933
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2934
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2935
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 <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	2941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2942 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2943 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	2944 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	2945 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	2946 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2947 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	2948 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2952 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	2953 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	2954 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	2955 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	2956 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	2957
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2958
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2959 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2960 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	2961 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	2962 <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	2963 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	2964
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2965
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2966 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2967 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2968 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	2969 (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	2970 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	2971 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	2972 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2973 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	2974 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2975 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	2976 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	2977
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2978
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2979 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2980 <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	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 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	2985 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2989
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2990 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2991 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2995 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	2996
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2997
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2998
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2999
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3000 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3001 <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	3002
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3003
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3004 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3005 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	3006 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	3007 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	3008 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	3009 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3010 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	3011
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 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	3015 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	3016
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3017
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 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3025 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	3026 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	3027 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	3028 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	3029 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	3030
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3031
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3032 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3033 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	3034 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	3035 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	3036 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3040 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	3041 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	3042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3043
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3046 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3047 <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	3048
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3051 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	3052 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	3053 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	3054 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	3055
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3058 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	3059
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3060 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3061 <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	3062 <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	3063 <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	3064 <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	3065 <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	3066 <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	3067 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	3068 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3069 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	3070 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	3071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3073
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3076 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3080 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	3081
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3084
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3085 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3086 <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	3087
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3088
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3089 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3090 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	3091 on all platforms.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3095 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	3096 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	3097 (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	3098 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	3099 (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	3100
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3101
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3102
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3103
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3104 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3105 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3109 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	3110
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3113
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3114 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3115 <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	3116
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3117
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3118 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3119 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	3120 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	3121 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3125
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3126 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3127 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3131 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	3132 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	3133 <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	3134 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	3135
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3138
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3139 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3140 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3144 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	3145
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3146
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3147
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 <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	3151
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3154 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3155 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	3156 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	3157 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	3158
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3160 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3161 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	3162 <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	3163 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	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 <p>
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="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	3170
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3172 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3173 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	3174
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3175
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3176
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3179 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3183 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	3184 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	3185 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	3186 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	3187 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	3188 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	3189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3190 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3191 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	3192 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3193 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	3194 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	3195 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	3196 when the loop ends.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3199 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3200 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	3201 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3207 <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	3208
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 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	3212 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	3213 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3214 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	3215 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	3216 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3217 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	3218 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3219 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	3220 (see below).
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3223 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3224 The available formats are
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3226 <ul>
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 <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	3229 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	3230 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	3231 (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	3232 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	3233 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	3234 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	3235 (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	3236 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	3237 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3238
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3239 <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	3240 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	3241 </li>
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 <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	3244 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	3245 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	3246 </li>
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 <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	3249 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	3250 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	3251 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	3252 </li>
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 <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	3255 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	3256 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	3257 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3258
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3259 <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	3260 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	3261 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	3262 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	3263 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	3264 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	3265 </li>
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 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3268 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	3269
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3270
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3271
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 <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	3275
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3278 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	3279 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	3280 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	3281 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	3282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3283 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3284 <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	3285 <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	3286 <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	3287 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3288 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	3289 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	3290 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	3291 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	3292
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3293
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3294 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3295 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	3296 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	3297 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	3298 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	3299 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	3300 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	3301 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	3302 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3306
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3307 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3308 <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	3309
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3310
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3311 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3312 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	3313 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	3314
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3315 <ul>
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 <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	3318 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	3319 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3321 <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	3322 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	3323 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	3324 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	3325 </li>
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 <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	3328 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	3329 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	3330 (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	3331 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3332
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3333 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3334 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	3335 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	3336 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	3337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3338
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3342 <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	3343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3344
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3345 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3346 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	3347 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	3348
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3350 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3351 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	3352 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	3353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3354
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3355
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3356
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3357
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 <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	3361
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3362 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3363 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	3364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3365
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3366 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3367 <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	3368
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3371 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	3372 used by the program.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3373
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3374
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3375
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3376
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3377 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3378 <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	3379
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 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	3383 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	3384
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3387 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	3388 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	3389 (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	3390 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	3391
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3393 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3394 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	3395 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	3396 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3397 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	3398 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	3399 <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	3400 <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	3401 <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	3402 <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	3403 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	3404 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	3405 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	3406
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3407
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3408 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3409 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	3410 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	3411 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	3412
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3415 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3416 <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	3417 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	3418 (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	3419
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3420
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3421 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3422 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3423 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	3424 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	3425
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3426
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3427
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3428
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3429 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3430 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3434 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	3435 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	3436 (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	3437 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	3438 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	3439
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3440
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3441
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3444 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3448 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	3449 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	3450 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	3451 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	3452 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	3453 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3454 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	3455 as follows:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3456
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3457 <ul>
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 <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	3460 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3461 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	3462 </li>
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 <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	3465 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	3466 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	3467 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3468
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3469 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3470
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3471 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3472 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	3473 <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	3474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3476
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3479 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3483 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	3484 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	3485 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	3486 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	3487 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	3488 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	3489 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	3490 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	3491
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3494 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	3495 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	3496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3497
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3499
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3500 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3501 <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	3502
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3504 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3505 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	3506 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	3507
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3508
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3511 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3512 <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	3513
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3514
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3515 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3516 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	3517 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3518 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	3519 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	3520
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3521
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3525 <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	3526
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3528 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3529 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	3530 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	3531 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3535
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3536 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3537 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3541 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	3542 <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	3543 <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	3544 <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	3545 <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	3546 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	3547 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	3548 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	3549
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3550
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3551 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3552 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	3553 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	3554 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	3555 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	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 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	3560 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	3561 for the given category.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3565 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	3566 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	3567
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3570
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3571 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3572 <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	3573
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3574
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3575 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3576 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	3577 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	3578 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	3579 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3580 <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	3581 <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	3582 <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	3583 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	3584 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	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 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	3589 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	3590 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	3591 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	3592 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	3593 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	3594 <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	3595
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3596
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3597
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3600 <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	3601
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3602
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3603 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3604 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	3605 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	3606 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	3607 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	3608
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3609
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3610 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3611 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3612 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	3613 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3614 (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	3615 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	3616 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	3617 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	3618
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3621 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3622 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	3623 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	3624
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3625
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3626
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3627
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3630
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3631 <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	3632
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3633 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3634 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3635 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	3636 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	3637 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3638 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	3639 (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	3640 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	3641 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	3642 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	3643 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	3644 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	3645
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3646
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3647 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3648 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	3649 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	3650 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	3651 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	3652 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3653 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3657 <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	3658
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 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	3662 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	3663 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	3664 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	3665 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	3666 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	3667 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	3668
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3669
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3670 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3671 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	3672 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	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 <p>
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="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	3679
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3680
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3681 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3682 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	3683 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	3684 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	3685 (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	3686
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3688
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3690 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3691 <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	3692
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3693
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3694 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3695 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	3696 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	3697 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	3698 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	3699 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3700 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	3701 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	3702 (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	3703 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3704 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	3705 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	3706
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3707
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3708 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3709 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	3710 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	3711 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	3712 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	3713 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3714 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	3715 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	3716 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3717 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	3718 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	3719 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3720
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3721
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3722 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3723 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	3724 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	3725 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	3726 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	3727 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	3728 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	3729
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3733 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3734 <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	3735
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3736
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3737 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3738 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	3739 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	3740 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	3741 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3745 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	3746 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	3747 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	3748 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	3749 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	3750 -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	3751 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	3752 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	3753 (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	3754
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3757 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	3758 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	3759 (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	3760 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	3761
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3762
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3763 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3764 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	3765 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	3766
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3767
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3768
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3769
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3770 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3771 <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	3772
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3773
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3774 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3775 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	3776 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3782 <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	3783
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 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	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 <p>
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="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	3793
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3794
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3795 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3796 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	3797 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	3798 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3802 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	3803 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	3804 (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	3805
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3809 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3810 <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	3811
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3812
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3813 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3814 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	3815 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	3816 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3817
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3818
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3822 <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	3823
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3824
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3825 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3826 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	3827 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	3828 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	3829 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	3830 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3831
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3832 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3833 <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	3834 <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	3835 <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	3836 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3837 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3838 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	3839 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	3840
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3841
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3842 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3843 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3844 <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	3845
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3846
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3847 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3848 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	3849 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	3850 <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	3851 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3852 <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	3853 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3854 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	3855 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3856 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	3857 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3858 (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	3859 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	3860
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3863
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3864 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3865 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3869 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	3870 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	3871 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	3872 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	3873 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	3874 (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	3875 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3879 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	3880 variable indices and names.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3881
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3882
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3885 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3886 <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	3887
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3888
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3889 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3890 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	3891 (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	3892 Returns <code>value</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3893
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3897 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3898 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3902 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	3903 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	3904 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	3905 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3906 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	3907
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3908
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3909
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3912 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3916 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	3917 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	3918 <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	3919
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3920
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3921 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3922 Returns <code>udata</code>.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3928 <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	3929
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3930
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3931 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3932 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	3933 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	3934 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3935 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	3936 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	3937 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	3938 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	3939 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3940 (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	3941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3942
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3943
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 <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	3947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3948
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3949 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3950 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	3951 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	3952 from the given function.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3956 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	3957 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3958 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	3959 (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	3960 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	3961
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3962
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3966 <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	3967
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3969 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3970 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	3971 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	3972
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3973
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3974
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3975
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3976
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 <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	3980
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3981 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3982 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	3983 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	3984 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	3985 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	3986 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	3987 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	3988 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3989 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	3990 Its usage is:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3991
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3992 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3993 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3994 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3995 The options are:
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3998 <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	3999 <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	4000 <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	4001 <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	4002 <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	4003 <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	4004 <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	4005 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4006 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	4007 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4008 <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	4009 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	4010 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	4011
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4013 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4014 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	4015 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	4016 (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	4017 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4018 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	4019 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	4020 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	4021
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4023 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4024 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	4025 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	4026 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4027 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	4028 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4029 <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	4030 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4034 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	4035 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	4036
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4037 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4038 $ 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	4039 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4040 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	4041 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	4042 (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	4043
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4044
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4045 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4046 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4047 <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	4048 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	4049 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	4050 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	4051 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4052 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	4053 (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	4054 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4055 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	4056
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4057 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4058 $ 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	4059 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4060 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	4061
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4062 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4063 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	4064 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4065 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4066 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4067 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	4068 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	4069 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	4070 For instance, the call
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4073 $ 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	4074 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4075 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	4076 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	4077 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	4078 <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	4079 (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	4080 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	4081
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4083 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4084 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4085 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	4086 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4087 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	4088 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	4089 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	4090 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	4091 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	4092 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4096 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	4097 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	4098 If the error object is not a string but
429 e3a6d9dbd694 rename __tostring to __to_string Franklin Schmidt <fschmidt@gmail.com> parents: 428 diff changeset	4099 has a metamethod <code>__to_string</code>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4100 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	4101 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	4102 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	4103
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4104
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4105 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4106 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4107 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	4108 (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	4109 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	4110 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	4111
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4112
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4113 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4114 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	4115 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	4116 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4117 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	4118 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	4119 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	4120 as in
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4123 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4124 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4125 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4126 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	4127 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	4128 then
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4129
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4130 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4131 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4132 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4133 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	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 <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	4138
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4139 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4140 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	4141 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	4142 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	4143 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	4144 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4145 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	4146
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4147
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4148 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4149 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	4150 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	4151 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	4152 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	4153 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4154 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	4155 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4156 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	4157 using a new version.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4158
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4160 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4161 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	4162 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4163 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	4164
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4165
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4166 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4167 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	4168 change between versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4169
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4170
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4172 <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	4173 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4174
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4175 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4176 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	4177 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	4178 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	4179 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4180 (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	4181 can give different results.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4185 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	4186 (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	4187 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	4188 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	4189 (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	4190 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4191 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	4192 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4193 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	4194 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	4195 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4197 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4198 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	4199 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	4200 (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	4201 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	4202 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	4203 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	4204
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 (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	4208 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	4209 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	4210 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4213 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	4214 (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	4215 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4217 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4218
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4220
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4221
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4222 <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	4223 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4224
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4225 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4226 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	4227 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	4228 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	4229 (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	4230 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	4231 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4234 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	4235 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	4236 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4237
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4238 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4239 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	4240 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	4241 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4244 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	4245 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	4246 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4247
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4248 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4249 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	4250 <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	4251 <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	4252 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	4253 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	4254 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	4255 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	4256 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4257 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	4258 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4259 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4262 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	4263 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	4264 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	4265 (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	4266 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	4267 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	4268 (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	4269 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	4270 </li>
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 </ul>
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4277 <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	4278
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4281
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4282 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4283 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	4284 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	4285 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	4286 Adapt your code accordingly.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4287 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4288
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4289 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4290 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	4291 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	4292 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4295 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	4296 (<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	4297 <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	4298 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4299 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	4300 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4301
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4302 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4303 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	4304 (<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	4305 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4306 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	4307 (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	4308 </li>
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 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4311
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4312
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4313
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 <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	4316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4317 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4318 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	4319 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	4320 {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	4321 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	4322 (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	4323 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	4324 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4325 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	4326
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4327
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4328
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4329
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4330 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4331
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4332 chunk ::= block
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 block ::= {stat} [retstat]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4335
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4336 stat ::= ‘<b>;</b>’ \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4337 varlist ‘<b>=</b>’ explist \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4338 functioncall \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4339 label \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4340 <b>break</b> \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4341 <b>goto</b> Name \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4342 <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	4343 <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	4344 <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	4345 <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	4346 <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	4347 <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	4348 <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	4349 <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	4350 <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	4351
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4352 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	4353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4354 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	4355
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4356 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	4357
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4358 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	4359
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4360 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	4361
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4362 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	4363
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4364 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	4365
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4366 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	4367 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	4368
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4369 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	4370
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4371 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	4372
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4373 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	4374
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4375 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	4376
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4377 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	4378
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4379 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	4380
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4381 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	4382
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4383 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	4384
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4385 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	4386
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4387 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	4388
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4389 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	4390 ‘<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	4391 ‘<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	4392 <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	4393
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4394 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	4395
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4396 </pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4397
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4398 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4399
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4400
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4401
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>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4408 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4409 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4410 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	4411 </SMALL>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4412 <!--
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4413 Last change: minor edit
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e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4415
391 2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	4416 </body>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	4417 </html>

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