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

annotate website/src/manual.html.luan @ 695:5042e487d717

documentation

author	Franklin Schmidt <fschmidt@gmail.com>
date	Wed, 20 Apr 2016 21:09:48 -0600
parents	ca169567ce07
children	87970832a3c3

rev	line source
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1 local Luan = require "luan:Luan.luan"
ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2 local Io = require "luan:Io.luan"
ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	3 local Html = require "luan:Html.luan"
ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	4 local Http = require "luan:http/Http.luan"
ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	5 local Shared = require "site:/Shared.luan"
505 7bc63886d4f2 web page modules now return a function Franklin Schmidt <fschmidt@gmail.com> parents: 503 diff changeset	6
7bc63886d4f2 web page modules now return a function Franklin Schmidt <fschmidt@gmail.com> parents: 503 diff changeset	7
7bc63886d4f2 web page modules now return a function Franklin Schmidt <fschmidt@gmail.com> parents: 503 diff changeset	8 return function()
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	9 Io.stdout = Http.response.text_writer()
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	10 %>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom Franklin Schmidt <fschmidt@gmail.com> parents: 389 diff changeset	11 <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	12 <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	13 <title>Luan Reference Manual</title>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	14 <style>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	15 @import "/site.css";
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	16 </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	17 </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	18 <body>
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	19
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	20 <div container>
387 23d075ce1e48 add website/src/Shared.luan Franklin Schmidt <fschmidt@gmail.com> parents: 386 diff changeset	21 <% Shared.header() %>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	22
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	23 <h1>Luan Reference Manual</h1>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	24
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	25 <p small>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	26 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	27 Freely available under the terms of the
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	28 <a href="http://www.lua.org/license.html">Lua license</a>.
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	29 Modified for Luan.
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	30 </p>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	31
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	32 <hr/>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	33
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	34 <h2>Contents</h2>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	35
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	36 <div contents><a href="#intro">Introduction</a></div>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	37
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	38 <div contents>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	39 <a href="#basic">Basic Concepts</a>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	40 <ul>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	41 <li><a href="#types">Values and Types</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	42 <li><a href="#env">Environments</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	43 <li><a href="#error">Error Handling</a></li>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	44 <li><a href="#meta">Metatables and Metamethods</a></li>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	45 <li><a href="#gc">Garbage Collection</a></li>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	46 </ul>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	47 </div>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	48
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	49 <div contents>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	50 <a href="#lang">The Language</a>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	51 <ul>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	52 <li><a href="#lex">Lexical Conventions</a></li>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	53 <li><a href="#vars">Variables</a></li>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	54 <li>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	55 <a href="#stmts">Statements</a>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	56 <ul>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	57 <li><a href="#blocks">Blocks</a></li>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	58 <li><a href="#chunks">Chunks</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	59 <li><a href="#assignment">Assignment</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	60 <li><a href="#control">Control Structures</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	61 <li><a href="#for">For Statement</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	62 <li><a href="#fn_stmt">Function Calls as Statements</a></li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	63 <li><a href="#local_stmt">Local Declarations</a></li>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	64 <li><a href="#template_stmt">Template Statements</a></li>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	65 </ul>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	66 </li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	67 <li>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	68 <a href="#expressions">Expressions</a>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	69 <ul>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	70 <li><a href="#arithmetic">Arithmetic Operators</a></li>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	71 <li><a href="#conversions">Coercions and Conversions</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	72 <li><a href="#relational">Relational Operators</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	73 <li><a href="#logical_ops">Logical Operators</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	74 <li><a href="#concatenation">Concatenation</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	75 <li><a href="#length">The Length Operator</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	76 <li><a href="#precedence">Precedence</a></li>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	77 <li><a href="#constructors">Table Constructors</a></li>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	78 <li><a href="#fn_calls">Function Calls</a></li>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	79 <li><a href="#fn_def">Function Definitions</a></li>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	80 <li><a href="#template_expr">Template Expressions</a></li>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	81 </ul>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	82 </li>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	83 <li><a href="#visibility">Visibility Rules</a></li>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	84 </ul>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	85 </div>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	86
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	87 <div contents>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	88 <a href="#libs">Standard Libraries</a>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	89 <ul>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	90 <li><a href="#default_lib">Default Environment</a></li>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	91 <li><a href="#luan_lib">Basic Functions</a></li>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	92 <li><a href="#package_lib">Modules</a></li>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	93 <li><a href="#string_lib">String Manipulation</a></li>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	94 <li><a href="#binary_lib">Binary Manipulation</a></li>
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	95 <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	96 <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	97 <li><a href="#math_lib">Mathematical Functions</a></li>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	98 </ul>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	99 </div>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	100
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	101 <hr/>
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	102
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	103
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	104 <h2 heading><a name="intro">Introduction</a></h2>
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	105
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	106 <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	107
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	108 <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	109
f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	110 <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	111
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	112
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	113 <h2 heading><a name="basic">Basic Concepts</a></h2>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	114
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	115 <p>This section describes the basic concepts of the language.</p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	116
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	117 <h3 heading><a name="types">Values and Types</a></h3>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	118
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	119 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	120 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	121 This means that
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	122 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	123 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	124 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	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>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	128 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	129 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	130 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	131
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	132
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	133 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	134 There are eight basic types in Luan:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	135 <em>nil</em>, <em>boolean</em>, <em>number</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	136 <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	137 and <em>table</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	138 <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	139 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	140 it usually represents the absence of a useful value.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	141 <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	142 <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	143 <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	144 <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	145 integer numbers and real (floating-point) numbers.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	146 <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	147 the underlying Java implementation.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	148
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	149 <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	150 <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	151
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	152
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	153 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	154 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	155 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	156 Both are represented by the type <em>function</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	157
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	158
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	159 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	160 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	161 be stored in Luan variables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	162 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	163 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	164 except assignment and identity test.
513 0dfc01d8d42d rename type "userdata" to "java" Franklin Schmidt <fschmidt@gmail.com> parents: 512 diff changeset	165 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	166
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	167
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	168
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	169 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	170 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	171 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	172 but with any Luan value except <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	173 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	174 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	175 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	176 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	177 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	178
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	179
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	180 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	181 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	182 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	183 symbol tables, sets, records, graphs, trees, etc.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	184 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	185 The language supports this representation by
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	186 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	187 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	188 (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	189
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 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	192 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	193 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	194 for some non-negative integer <em>n</em>,
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	195 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	196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	197
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	198 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	199 Like indices,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	200 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	201 In particular,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	202 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	203 table fields can contain functions.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	204 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	205
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	207 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	208 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	209 the definition of raw equality in the language.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	210 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	211 denote the same table element
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	212 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	213 (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	214 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	215 are equal to their respective integers
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	216 (e.g., <code>1.0 == 1</code>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	217
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	218
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	219 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	220 Luan values are <em>objects</em>:
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	221 variables do not actually <em>contain</em> values,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	222 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	223 Assignment, parameter passing, and function returns
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	224 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	225 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	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 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	229 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	230 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	231
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	232
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	233
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	234
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	235
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	236 <h3 heading><a name="env">Environments</a></h3>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	237
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	238 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	239 The environment of a chunk starts with only two local variables: <code><a href="#require">require</a></code> and <code><a href="#java">java</a></code>. These are functions are 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	240
d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	241 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	242 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	243 any reference to a free name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	244 (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	245 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	246
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	247
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	248 <h3 heading><a name="error">Error Handling</a></h3>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	249
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	250 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	251 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	252 <a href="#Luan.error"><code>error</code></a> function.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	253 If you need to catch errors in Luan,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	254 you can use <a href="#Luan.pcall"><code>pcall</code></a> or <a href="#Luan.try"><code>try</code></a>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	255 to call a given function in <em>protected mode</em>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	258 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	259 Whenever there is an error,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	260 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	261 is propagated with information about the error.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	262 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	263
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	264
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	265
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	266 <h3 heading><a name="meta">Metatables and Metamethods</a></h3>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	267
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	268 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	269 Every table in Luan can have a <em>metatable</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	270 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	271 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	272 under certain special operations.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	273 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	274 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	275 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	276 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	277 If it finds one,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	278 Luan calls this function to perform the addition.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	279
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	280
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	281 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	282 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	283 the corresponding values are called <ii>metamethods</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	284 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	285 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	286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	288 <p>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	289 You can query the metatable of any table
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	290 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	291
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	292
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	293 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	294 You can replace the metatable of tables
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	295 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	296
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	297
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	298 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	299 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	300 arithmetic operations, bitwise operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	301 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	302
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	303
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	304 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	305 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	306 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	307 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	308 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	309 for instance, the key for operation "add" is the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	310 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	311 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	312 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	313 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	314 with the following code:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	315
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	316 <pre>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	317 raw_get(get_metatable(obj) or {}, "__" .. event_name)
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	318 </pre>
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	319
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	320 <p>
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	321 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	322
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	323 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	324
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	325 <li><p><b>"add": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	326 the <code>+</code> operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	327
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	328 If any operand for an addition is a table,
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	329 Luan will try to call a metamethod.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	330 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	331 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	332 then Luan will check the second operand.
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	333 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	334 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	335 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	336 (adjusted to one value)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	337 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	338 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	339 it raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	340 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	341
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	342 <li><p><b>"sub": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	343 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	344
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	345 Behavior similar to the "add" operation.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	346 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	347
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	348 <li><p><b>"mul": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	349 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	350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	351 Behavior similar to the "add" operation.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	352 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	353
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	354 <li><p><b>"div": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	355 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	356
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	357 Behavior similar to the "add" operation.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	358 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	359
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	360 <li><p><b>"mod": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	361 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	362
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	363 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	364 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	365
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	366 <li><p><b>"pow": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	367 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	368
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	369 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	370 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	371
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	372 <li><p><b>"unm": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	373 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	374
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	375 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	376 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	377
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	378 <li><p><b>"concat": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	379 the <code>..</code> (concatenation) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	380
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	381 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	382 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	383
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	384 <li><p><b>"len": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	385 the <code>#</code> (length) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	386
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	387 If there is a metamethod,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	388 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	389 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	390 (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	391 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	392 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	393 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	394 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	395 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	396
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	397 <li><p><b>"eq": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	398 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	399
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	400 Behavior similar to the "add" operation,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	401 except that Luan will try a metamethod only when the values
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	402 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	403 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	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>"lt": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	408 the <code><</code> (less than) operation.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	409
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	410 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	411 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	412 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	413
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	414 <li><p><b>"le": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	415 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	416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	417 Unlike other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	418 The less-equal operation can use two different events.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	419 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	420 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	421 If it cannot find such a metamethod,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	422 then it will try the "<code>__lt</code>" event,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	423 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	424 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	425 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	426 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	427
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	428 <li><p><b>"index": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	429 The indexing access <code>table[key]</code>.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	430
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	431 This event happens
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	432 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	433 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	434
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	435
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	436 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	437 Despite the name,
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	438 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	439 If it is a function,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	440 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	441 Otherwise
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	442 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	443 (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	444 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	445 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	446
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	447 <li><p><b>"new_index": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	448 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	449
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	450 Like the index event,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	451 this event happens when
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	452 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	453 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	454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	455
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	456 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	457 Like with indexing,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	458 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	459 If it is a function,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	460 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	461 If it is a table,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	462 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	463 (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	464 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	465
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	466
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	467 <p>
428 df95199ca4c0 rename __newindex to __new_index Franklin Schmidt <fschmidt@gmail.com> parents: 418 diff changeset	468 Whenever there is a "new_index" metamethod,
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	469 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	470 (If necessary,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	471 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	472 to do the assignment.)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	473 </li>
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 </ul>
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	479
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	480 <h3 heading><a name="gc">Garbage Collection</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	481
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	482 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	483 Luan uses Java's garbage collection.
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
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	487
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	488
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	489 <h2 heading><a name="lang">The Language</a></h2>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	490
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	491 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	492 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	493 In other words,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	494 this section describes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	495 which tokens are valid,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	496 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	497 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	498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	499
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	500 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	501 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	502 in which
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	503 {<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	504 [<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	505 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	506 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	507 and other terminal symbols are shown like ‘<b>=</b>’.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	508 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	509 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	510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	511
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	512
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	513 <h3 heading><a name="lex">Lexical Conventions</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	514
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	515 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	516 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	517 between lexical elements (tokens),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	518 except as delimiters between names and keywords.
685 1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	519 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	520
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	521 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	522 <em>Names</em>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	523 (also called <em>identifiers</em>)
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	524 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	525 digits, and underscores,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	526 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	527 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	528
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	529
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	530 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	531 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	532 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	533
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	534
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	535 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	536 and break do else elseif end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	537 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	538 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	539 then true until while
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	540 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	541
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	542 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	543 Luan is a case-sensitive language:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	544 <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	545 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	546
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	547
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	548 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	549 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	550
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	551 <pre>
371 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 ( ) { } [ ] ::
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	556 ; : , . .. ...
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	557 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	558
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	559 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	560 <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	561 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	562 and can contain the following C-like escape sequences:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	563 '<code>\a</code>' (bell),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	564 '<code>\b</code>' (backspace),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	565 '<code>\f</code>' (form feed),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	566 '<code>\n</code>' (newline),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	567 '<code>\r</code>' (carriage return),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	568 '<code>\t</code>' (horizontal tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	569 '<code>\v</code>' (vertical tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	570 '<code>\\</code>' (backslash),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	571 '<code>\"</code>' (quotation mark [double quote]),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	572 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	573 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	574 results in a newline in the string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	575 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	576 of white-space characters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	577 including line breaks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	578 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	579 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	580 into the string contents.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	583 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	584 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	585 This can be done
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	586 with the escape sequence <code>\x<em>XX</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	587 where <em>XX</em> is a sequence of exactly two hexadecimal digits,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	588 or with the escape sequence <code>\<em>ddd</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	589 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	590 (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	591 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	592
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	595 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	596 enclosed by <em>long brackets</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	597 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	598 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	599 opening square bracket.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	600 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	601 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	602 and so on.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	603 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	604 for instance,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	605 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	606 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	607 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	608 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	609 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	610 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	611 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	612 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	613 (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	614 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	615 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	616
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 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	619 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	620 explicitly affected by the previous rules represents itself.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	621 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	622 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	623 some control characters.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	624 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	625 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	626 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	627
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	630 For convenience,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	631 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	632 the newline is not included in the string.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	633 As an example
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	634 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	635
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	636 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	637 a = 'alo\n123"'
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 = '\97lo\10\04923"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	640 a = [[alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	641 123"]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	642 a = [==[
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	643 alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	644 123"]==]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	645 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	646
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	647 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	648 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	649 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	650 and an optional decimal exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	651 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	652 Luan also accepts hexadecimal constants,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	653 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	654 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	655 plus an optional binary exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	656 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	657 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	658 denotes a float;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	659 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	660 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	661
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	662 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	663 3 345 0xff 0xBEBADA
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	664 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	665
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	666 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	667 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	668
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	669 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	670 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	671 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	672 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	673
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	674 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	675 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	676 anywhere outside a string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	677 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	678 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	679 which runs until the end of the line.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	680 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	681 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	682 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	683
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
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	688 <h3 heading><a name="vars">Variables</a></h3>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	690 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	691 Variables are places that store values.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	692 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	693 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	694
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	695 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	696 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	697 (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	698 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	699
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	700 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	701 var ::= Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	702 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	703
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	704 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	705 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	706
512 d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	707 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	708 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	709 local variables can be freely accessed by functions
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	710 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	711
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	712
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	713 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	714 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	715
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	716 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	717 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	718
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	719 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	720 var ::= prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	721 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	722
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	723 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	724 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	725 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	726 a call <code>gettable_event(t,i)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	727 (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	728 <code>gettable_event</code> function.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	729 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	730 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	731
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 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	734 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	735 <code>var["Name"]</code>:
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	736
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	737 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	738 var ::= prefixexp ‘<b>.</b>’ Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	739 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	740
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	741 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	742 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	743 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	744 Due to the way that chunks are compiled,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	745 <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	746
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 <h3 heading><a name="stmts">Statements</a></h3>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	752
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	753 <p>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	754 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	755 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	756 This set includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	757 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	758 and variable declarations.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	759
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
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	762 <h4 heading><a name="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	763
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	764 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	765 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	766 which are executed sequentially:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	767
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	768 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	769 block ::= {stat}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	770 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	771
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	772 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	773 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	774 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	775 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	776 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	777
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	778 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	779 stat ::= ‘<b>;</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	780 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	781
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	782 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	783 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	784
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	785 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	786 stat ::= <b>do</b> block <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	787 </pre>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	788
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	789 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	790 Explicit blocks are useful
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	791 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	792 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	793 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	794 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	795
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	796
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
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	800 <h4 heading><a name="chunks">Chunks</a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	801
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	802 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	803 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	804 Syntactically,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	805 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	806
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	807 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	808 chunk ::= block
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	809 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	810
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	811 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	812 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	813 with a variable number of arguments
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	814 (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	815 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	816 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	817
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	818
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	819 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	820 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	821 To execute a chunk,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	822 Luan first <em>loads</em> it,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	823 compiling the chunk's code,
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	824 and then Luan executes the compiled code.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	825
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	826
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
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	830 <h4 heading><a name="assignment">Assignment</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	831
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	832 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	833 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	834 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	835 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	836 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	837 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	838
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	839 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	840 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	841 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	842 explist ::= exp {‘<b>,</b>’ exp}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	843 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	844
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	845 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	846 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	847
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	848
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	849 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	850 Before the assignment,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	851 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	852 the list of variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	853 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	854 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	855 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	856 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	857 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	858 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	859 before the adjustment
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	860 (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	861
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	862
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	863 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	864 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	865 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	866 Thus the code
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	867
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	868 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	869 i = 3
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	870 i, a[i] = i+1, 20
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	871 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	872
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	873 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	874 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	875 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	876 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	877 Similarly, the line
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	878
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	879 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	880 x, y = y, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	881 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	882
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	883 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	884 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	885 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	886
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	887 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	888 x, y, z = y, z, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	889 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	890
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	891 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	892 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	893
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	894
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	895 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	896 The 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	897 and table fields can be changed via metatables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	898 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	899 <code>settable_event(t,i,val)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	900 (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	901 <code>settable_event</code> function.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	902 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	903 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	904
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	905
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	906 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	907 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	908 is equivalent to the assignment
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	909 <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	910 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	911
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	912
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 <h4 heading><a name="control">Control Structures</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	915
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	916 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	917 The control structures
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	918 <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	919 familiar syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	920
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	921 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	922 stat ::= <b>while</b> exp <b>do</b> block <b>end</b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	923 stat ::= <b>repeat</b> block <b>until</b> exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	924 stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	925 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	926
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	927 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	928 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	929
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	930
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	931 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	932 The condition expression of a
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	933 control structure must be a boolean.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	934 Any other value type will produce an error.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	935 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	936
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	938 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	939 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	940 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	941 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	942 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	943 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	944
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	945
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	946 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	947 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	948 <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	949 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	950
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	951
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	952 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	953 stat ::= <b>break</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	954 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	955
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	956 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	957 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	958
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	959
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	960 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	961 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	962 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	963 (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	964
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	965 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	966 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	967
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	968 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	969 stat ::= <b>return</b> [explist] [‘<b>;</b>’]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	970 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	971
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	972
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	973
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	974
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	975 <h4 heading><a name="for">For Statement</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	976
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	977 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	978 The <b>for</b> statement works over functions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	979 called <em>iterators</em>.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	980 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	981 stopping when this new value is <b>nil</b>.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	982 The <b>for</b> loop has the following syntax:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	983
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	984 <pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	985 stat ::= <b>for</b> namelist <b>in</b> exp <b>do</b> block <b>end</b>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	986 namelist ::= Name {‘<b>,</b>’ Name}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	987 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	988
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	989 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	990 A <b>for</b> statement like
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	991
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	992 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	993 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	994 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	995
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	996 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	997 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	998
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	999 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1000 do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1001 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	1002 while true do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1003 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	1004 if <em>var_1</em> == nil then break end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1005 <em>block</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1006 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1007 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1008 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1009
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1010 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1011 Note the following:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1013 <ul>
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 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1016 <code><em>exp</em></code> is evaluated only once.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1017 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	1018 </li>
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>f</em></code> is an invisible variable.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1022 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	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>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1026 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	1027 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1029 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1030 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	1031 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	1032 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	1033 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	1034 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1035
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1036 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1037
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1038
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1039
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1040
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1041 <h4 heading><a name="fn_stmt">Function Calls as Statements</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1042
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1043 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1044 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	1045 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	1046
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1047 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1048 stat ::= functioncall
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1049 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1050
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1051 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1052 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	1053 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	1054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1056
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1057 <h4 heading><a name="local_stmt">Local Declarations</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 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	1061 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	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 ::= <b>local</b> namelist [‘<b>=</b>’ explist]
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 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	1069 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	1070 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	1071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1073 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1074 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	1075 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	1076
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1077
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1078 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1079 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	1080
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1081
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1082 <h4 heading><a name="template_stmt">Template Statements</a></h4>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1083
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1084 <p>Template statements are based on <a href="#template_expr">template exressions</a> and provide the full equivalent of <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a> but in a general way. Template statements write the equivalent template exression to standard output. For example:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1085
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1086 <pre><%=Html.encode[[
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1087 local name = "Bob"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1088 %>
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1089 Hello <%= name %>!
85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1090 Bye <%= name %>.
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1091 <%
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1092 ]]%></pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1093
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1094 <p>is equivalent to the code:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1095
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1096 <pre><%=Html.encode[[
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1097 local name = "Bob"
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1098 require("luan:Io.luan").stdout.write( %>
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1099 Hello <%= name %>!
85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1100 Bye <%= name %>.
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1101 <% )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1102 ]]%></pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1103
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1104
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1105
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1106 <h3 heading><a name="expressions">Expressions</a></h3>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1107
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1108 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1109 The basic expressions in Luan are the following:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1110
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1111 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1112 exp ::= prefixexp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1113 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	1114 exp ::= Numeral
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1115 exp ::= LiteralString
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1116 exp ::= functiondef
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1117 exp ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1118 exp ::= ‘<b>...</b>’
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1119 exp ::= exp binop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1120 exp ::= unop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1121 prefixexp ::= var \| functioncall \| ‘<b>(</b>’ exp ‘<b>)</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1122 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1123
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1124 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1125 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	1126 variables are explained in <a href="#vars">Variables</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1127 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	1128 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	1129 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	1130 Vararg expressions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1131 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	1132 directly inside a vararg function;
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1133 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	1134
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1135
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1136 <p>
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1137 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	1138 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	1139 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	1140 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	1141 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	1142 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	1143
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1144
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1145 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1146 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	1147 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	1148 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	1149 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	1150 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	1151 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	1152 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	1153 (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	1154 In all other contexts,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1155 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	1156 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	1157 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	1158
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1160 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1161 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1162
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1163 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1164 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	1165 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	1166 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	1167 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	1168 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	1169 -- 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	1170 -- 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	1171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1172 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	1173 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	1174 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	1175 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	1176 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	1177 {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	1178 {...} -- 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	1179 {f(), nil} -- f() is adjusted to 1 result
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1180 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1182 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1183 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	1184 Thus,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1185 <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	1186 even if <code>f</code> returns several values.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1187 (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	1188 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	1189
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1190
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1191
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1192 <h4 heading><a name="arithmetic">Arithmetic Operators</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1193
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1194 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1195 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	1196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1197 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1198 <li><b><code>+</code>: </b>addition</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1199 <li><b><code>-</code>: </b>subtraction</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1200 <li><b><code>*</code>: </b>multiplication</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1201 <li><b><code>/</code>: </b>division</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1202 <li><b><code>%</code>: </b>modulo</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1203 <li><b><code>^</code>: </b>exponentiation</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1204 <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	1205 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1207 <p>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1208 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	1209
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1210 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1211 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	1212 that rounds the quotient towards minus infinite (floor division).
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1213 (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	1214
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1215
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1216
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1217 <h4 heading><a name="conversions">Coercions and Conversions</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1218
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1219 <p>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1220 Luan generally avoids automatic conversions.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1221 String concatenation automatically converts all of its arguments to strings.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1222
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1223 <p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1224 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	1225
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1226
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1227
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1228
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1229 <h4 heading><a name="relational">Relational Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1230
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1231 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1232 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	1233
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1234 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1235 <li><b><code>==</code>: </b>equality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1236 <li><b><code>~=</code>: </b>inequality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1237 <li><b><code><</code>: </b>less than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1238 <li><b><code>></code>: </b>greater than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1239 <li><b><code><=</code>: </b>less or equal</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1240 <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	1241 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1242 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	1243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1244
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1245 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1246 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	1247 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	1248 Otherwise, the values of the operands are compared.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1249 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	1250
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1251 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1252 Tables
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1253 are compared by reference:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1254 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	1255 Every time you create a new table,
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1256 it is different from any previously existing table.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1257 Closures are also compared by reference.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1258
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1259 <p>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1260 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	1261 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	1262
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1263 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1264 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	1265
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1266 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1267 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	1268 or vice versa.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1269 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1270 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	1271 entries in a table.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1272
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1273
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1274 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1275 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	1276
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1277
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1278 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1279 The order operators work as follows.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1280
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1281 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	1282 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	1283 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	1284 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	1285 then their values are compared according to the current locale.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1286 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	1287 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1288 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	1289 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	1290
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1291
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1292
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1293
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1294
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1295 <h4 heading><a name="logical_ops">Logical Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1296
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1297 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1298 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	1299 <b>and</b>, <b>or</b>, and <b>not</b>.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1300 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	1301 and anything else as true.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1302 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	1303 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	1304
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1305 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1306 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	1307 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	1308 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	1309 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	1310 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	1311 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	1312 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	1313 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	1314 that is,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1315 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	1316 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1317
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1318 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1319 10 or 20 --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1320 10 or error() --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1321 nil or "a" --> "a"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1322 nil and 10 --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1323 false and error() --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1324 false and nil --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1325 false or nil --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1326 10 and 20 --> 20
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1327 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1328
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1329 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1330 (In this manual,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1331 <code>--></code> indicates the result of the preceding expression.)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1332
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1333
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1334
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1335 <h4 heading><a name="concatenation">Concatenation</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1336
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1337 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1338 The string concatenation operator in Luan is
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1339 denoted by two dots ('<code>..</code>').
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1340 All operands are converted to strings.
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
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1343
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1344 <h4 heading><a name="length">The Length Operator</a></h4>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1347 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	1348 The length of a string is its number of characters.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1349 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	1350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1351
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1352 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1353 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	1354 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	1355
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1356
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1357 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1358 Unless a <code>__len</code> metamethod is given,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1359 the length of a table <code>t</code> is defined
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1360 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	1361 that is,
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1362 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	1363 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	1364 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	1365 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	1366
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1367 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1368 {10, 20, nil, 40}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1369 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1370
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1371 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1372 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	1373
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1374
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1375
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1376
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1377
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1378 <h4 heading><a name="precedence">Precedence</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1379
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1380 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1381 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	1382 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	1383
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1384 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1385 or
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1386 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1387 < > <= >= ~= ==
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1388 ..
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1389 + -
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1390 * / %
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1391 unary operators (not # -)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1392 ^
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1393 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1394
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1395 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1396 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1397 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	1398 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	1399 operators are right associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1400 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	1401
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1402
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1403
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1404
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 <h4 heading><a name="constructors">Table Constructors</a></h4>
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 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	1410 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	1411 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	1412 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	1413 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	1414
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1415 <pre>
604 b73f005f3735 table constructor now uses end_of_line as a delimiter Franklin Schmidt <fschmidt@gmail.com> parents: 589 diff changeset	1416 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	1417 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	1418 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	1419 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	1420 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1421
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1422 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1423 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	1424 with key <code>exp1</code> and value <code>exp2</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1425 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	1426 <code>["name"] = exp</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1427 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	1428 <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	1429 starting with 1.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1430 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	1431 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1432
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1433 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1434 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	1435 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1436
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1437 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1438 is equivalent to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1439
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1440 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1441 do
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1442 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1443 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1444 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	1445 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	1446 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	1447 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	1448 t[30] = 23
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1449 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	1450 a = t
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1451 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1452 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1453
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1454 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1455 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	1456 (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	1457
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1458
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1459 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1460 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	1461 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	1462 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	1463 (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	1464
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1465
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1466 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1467 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	1468 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	1469
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1473
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1474 <h4 heading><a name="fn_calls">Function Calls</a></h4>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1475
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1476 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1477 A function call in Luan has the following syntax:
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1478
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1479 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1480 functioncall ::= prefixexp args
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1481 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1482
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1483 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1484 In a function call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1485 first prefixexp and args are evaluated.
685 1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	1486 The value of prefixexp must have type <em>function</em>.
1e4b0bc0202d update documentation Franklin Schmidt <fschmidt@gmail.com> parents: 642 diff changeset	1487 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	1488 with the given arguments.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1489
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1490
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1491 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1492 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	1493
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1494 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1495 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	1496 args ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1497 args ::= LiteralString
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1498 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1499
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1500 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1501 All argument expressions are evaluated before the call.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1502 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	1503 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	1504 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	1505 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	1506 (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	1507 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	1508 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	1509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1510
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1511
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1512
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1513 <h4 heading><a name="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	1514
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1515 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1516 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	1517
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1518 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1519 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	1520 funcbody ::= ‘<b>(</b>’ [parlist] ‘<b>)</b>’ block <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1521 </pre>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1524 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	1525
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1526 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1527 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	1528 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	1529 funcname ::= Name {‘<b>.</b>’ Name} [‘<b>:</b>’ Name]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1530 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1531
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1532 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1533 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1534
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1535 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1536 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1537 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1538
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1539 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1540 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1541
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1542 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1543 f = function () <em>body</em> end
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 t.a.b.c.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 t.a.b.c.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 local function 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>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1571 local f; f = function () <em>body</em> end
562 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 not to
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>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1578 local f = function () <em>body</em> end
562 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 (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	1583 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	1584
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1585
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1586 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1587 A function definition is an executable expression,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1588 whose value has type <em>function</em>.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1589 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	1590 all its function bodies are precompiled too.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1591 Then, whenever Luan executes the function definition,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1592 the function is <em>instantiated</em> (or <em>closed</em>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1593 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	1594 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	1595
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1596
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1597 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1598 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	1599 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	1600
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1601 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1602 parlist ::= namelist [‘<b>,</b>’ ‘<b>...</b>’] \| ‘<b>...</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1603 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1604
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1605 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1606 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	1607 the list of arguments is adjusted to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1608 the length of the list of parameters,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1609 unless the function is a <em>vararg function</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1610 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	1611 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	1612 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	1613 instead, it collects all extra arguments and supplies them
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1614 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	1615 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	1616 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	1617 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	1618 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	1619 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	1620 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	1621 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	1622 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	1623 (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	1624
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1625
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1626 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1627 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	1628
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1629 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1630 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	1631 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	1632 function r() return 1,2,3 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1633 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1634
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1635 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1636 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	1637 to the vararg expression:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1638
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1639 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1640 CALL PARAMETERS
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1641
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1642 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	1643 f(3, 4) a=3, b=4
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1644 f(3, 4, 5) a=3, b=4
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1645 f(r(), 10) a=1, b=10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1646 f(r()) a=1, b=2
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1647
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1648 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	1649 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	1650 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	1651 g(5, r()) a=5, b=1, ... --> 2 3
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1652 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1653
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1654 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1655 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	1656 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	1657 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	1658 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	1659
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1660
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1661 <h4 heading><a name="template_expr">Template Expressions</a></h4>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1662
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1663 <p>Luan template expression are based on <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a>. Template expressions return multiple values. Here is an example:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1664
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1665 <pre><%=Html.encode[[
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1666 local name = "Bob"
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1667 write( %>Hello <%= name %>!<% )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1668 ]]%></pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1669
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1670 <p>This is equivalent to the code:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1671
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1672 <pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1673 local name = "Bob"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1674 write( "Hello ", name, "!" )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1675 </pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1676
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1677 <p>The strings in template expressions may be multiple lines.</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1678
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1679
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1680
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1681 <h3 heading><a name="visibility">Visibility Rules</a></h3>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1682
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1683 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1684 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	1685 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	1686 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	1687 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	1688 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1689
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1690 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1691 x = 10 -- global variable
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1692 do -- new block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1693 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	1694 print(x) --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1695 x = x+1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1696 do -- another block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1697 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	1698 print(x) --> 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1699 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1700 print(x) --> 11
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1701 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1702 print(x) --> 10 (the global one)
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1703 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1704
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1705 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1706 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	1707 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	1708 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	1709
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1710
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1711 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1712 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	1713 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	1714 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1715 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	1716 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	1717 inside the inner function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1718
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1719
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1720 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1721 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	1722 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1723 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1724
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1725 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1726 a = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1727 local x = 20
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1728 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	1729 local y = 0
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1730 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	1731 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1732 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1733
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1734 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1735 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	1736 (that is, ten instances of the anonymous function).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1737 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	1738 while all of them share the same <code>x</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1739
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1740
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1741
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1742
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1743
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1744 <h2 heading><a name="libs">Standard Libraries</a></h2>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1745
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1746 <p>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1747 The standard Luan libraries provide useful functions
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1748 that are implemented both in Java and in Luan itself.
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1749 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	1750 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	1751 (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	1752 others provide access to "outside" services (e.g., I/O).
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1753
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1754
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1755 <h3 heading><a name="default_lib">Default Environment</a></h3>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1756
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1757 <p>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1758 These are provided by default as local variables for any Luan code as described in <a href="#env">Environments</a>.
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1759
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1760
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1761 <h4 heading><a name="require"><code>java ()</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1762
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1763 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1764 This function 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.
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1765
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 <h4 heading><a name="require"><code>require (mod_uri)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1768
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1769 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1770 Example use:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1771
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1772 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1773 local Table = require "luan:Table.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1774 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1775
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1776 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1777 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1778
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1779 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1780 local function require(mod_name)
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1781 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	1782 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1783 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1784
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1785
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1786 <h3 heading><a name="luan_lib">Basic Functions</a></h3>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1787
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1788 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1789 Include this library by:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1790
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1791 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1792 local Luan = require "luan:Luan.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1793 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1794
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1795 <p>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1796 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	1797
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1798
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1799 <h4 heading><a name="Luan.assert" href="#Luan.assert"><code>Luan.assert (v [, message])</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1800
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1801 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1802 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1803
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1804 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1805 function Luan.assert(v,message)
472 f4aca5a5346a minor documentation Franklin Schmidt <fschmidt@gmail.com> parents: 470 diff changeset	1806 return v or <a href="#Luan.error">Luan.error</a>(message or "assertion failed!")
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1807 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1808 </pre>
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.assert_binary" href="#Luan.assert_binary"><code>Luan.assert_binary (v)</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>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1814 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1815
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1816 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1817 function Luan.assert_binary(v)
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1818 local v_type = Luan.type(v)
472 f4aca5a5346a minor documentation Franklin Schmidt <fschmidt@gmail.com> parents: 470 diff changeset	1819 return v_type == "binary" and v or <a href="#Luan.error">Luan.error</a>("bad argument #1 (binary expected, got "..v_type..")")
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1820 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1821 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1822
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1823
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1824 <h4 heading><a name="Luan.assert_boolean" href="#Luan.assert_boolean"><code>Luan.assert_boolean (v)</code></a></h4>
562 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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1827 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>boolean</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1828
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1829
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1830 <h4 heading><a name="Luan.assert_function" href="#Luan.assert_function"><code>Luan.assert_function (v)</code></a></h4>
626 53a50c70c5e2 add Luan.assert_function() and Http.run_later() Franklin Schmidt <fschmidt@gmail.com> parents: 604 diff changeset	1831
53a50c70c5e2 add Luan.assert_function() and Http.run_later() Franklin Schmidt <fschmidt@gmail.com> parents: 604 diff changeset	1832 <p>
53a50c70c5e2 add Luan.assert_function() and Http.run_later() Franklin Schmidt <fschmidt@gmail.com> parents: 604 diff changeset	1833 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>function</code>.
53a50c70c5e2 add Luan.assert_function() and Http.run_later() Franklin Schmidt <fschmidt@gmail.com> parents: 604 diff changeset	1834
53a50c70c5e2 add Luan.assert_function() and Http.run_later() Franklin Schmidt <fschmidt@gmail.com> parents: 604 diff changeset	1835
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1836 <h4 heading><a name="Luan.assert_integer" href="#Luan.assert_integer"><code>Luan.assert_integer (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1837
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1838 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1839 Asserts that <code>v</code> can be converted to Java type <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html">Integer</a> and returns an Integer.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1840
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1841
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1842 <h4 heading><a name="Luan.assert_long" href="#Luan.assert_long"><code>Luan.assert_long (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1843
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1844 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1845 Asserts that <code>v</code> can be converted to Java type <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Long.html">Long</a> and returns a Long.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1846
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1847
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1848 <h4 heading><a name="Luan.assert_number" href="#Luan.assert_number"><code>Luan.assert_number (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1849
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1850 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1851 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>number</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1852
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1853
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1854 <h4 heading><a name="Luan.assert_string" href="#Luan.assert_string"><code>Luan.assert_string (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1855
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1856 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1857 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>string</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1858
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1859
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1860 <h4 heading><a name="Luan.assert_table" href="#Luan.assert_table"><code>Luan.assert_table (v)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1861
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1862 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1863 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>table</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1864
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1865
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1866 <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	1867
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1868 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1869 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1870
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1871 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1872 function Luan.do_file(uri)
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1873 return <a href="#Luan.load_file">Luan.load_file</a>(uri)()
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1874 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1875 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1876
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1877
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1878
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1879 <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	1880
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1881 <p>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1882 Throws an error containing the message.
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1883
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1884 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1885 Could be defined as:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1886
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1887 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1888 function Luan.error(message)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1889 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1890 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1891 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1892
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1893
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1894
695 5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1895 <h4 heading><a name="Luan.eval" href="#Luan.eval"><code>Luan.eval (text [, source_name])</code></a></h4>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1896
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1897 <p>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1898 Evaluates <code>text</code> as a Luan expression.
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1899
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1900 <p>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1901 Could be defined as:
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1902
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1903 <pre>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1904 function Luan.eval(text,source_name)
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1905 return Luan.load( "return "..text, source_name or "eval" )()
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1906 end
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1907 </pre>
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1908
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1909
5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1910
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1911 <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	1912
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1913 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1914 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	1915 Otherwise,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1916 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	1917 returns the associated value.
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1918 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	1919
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1920
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1921 <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	1922
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1923 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1924 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	1925 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1926
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1927 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1928 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	1929 </pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1930
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1931 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1932 will iterate over the key–value pairs
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1933 (<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	1934 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	1935
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1936 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1937 Could be defined as:
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1938
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1939 <pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1940 function Luan.ipairs(t)
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1941 local i = 0
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1942 return function()
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1943 if i < #t then
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1944 i = i + 1
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1945 return i, t[i]
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1946 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1947 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1948 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1949 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1950
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1951
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1952
695 5042e487d717 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 693 diff changeset	1953 <h4 heading><a name="Luan.load" href="#Luan.load"><code>Luan.load (text, source_name [, env])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1954
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 Loads a chunk.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1957
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1958 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1959 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	1960 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	1961 returns the compiled chunk as a function;
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1962 otherwise, throws an error.
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1963
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1964 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1965 The <code>source_name</code> parameter is a string saying where the text came from. It is used to produce error messages.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1966
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1967 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1968 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	1969
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1970
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1971 <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	1972
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1973 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1974 Similar to <a href="#Luan.load"><code>load</code></a>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1975 but gets the chunk from file <code>file_uri</code>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1976 or from the standard input,
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1977 if no file uri is given.
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1978
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1979 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1980 Could be defined as:
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1981
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1982 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1983 function Luan.load_file(file_uri)
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1984 file_uri = file_uri or "stdin:"
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	1985 local f = Io.uri(file_uri)
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1986 f.exists() or <a href="#Luan.error">Luan.error</a>("file '"..file_uri.."' not found")
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1987 return <a href="#Luan.load">Luan.load</a>( f.read_text(), file_uri )
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1988 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1989 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1990
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1991
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	1992 <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	1993
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1994 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1995 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	1996
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1997 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1998 To print the current stack trace, you could do:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1999
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2000 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2001 Io.print( Luan.new_error "stack" )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2002 </pre>
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.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	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 If <code>t</code> has a metamethod <code>__pairs</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2009 calls it with <code>t</code> as argument and returns the
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2010 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2014 Otherwise,
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2015 returns a function
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2016 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2017
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2018 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2019 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	2020 </pre>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2023 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	2024
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2027 <h4 heading><a name="Luan.pcall" href="#Luan.pcall"><code>Luan.pcall (f [, arg1, ···])</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2028
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2029 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2030 Calls function <code>f</code> with
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2031 the given arguments in <em>protected mode</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2032 This means that any error inside <code>f</code> is not propagated;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2033 instead, <code>pcall</code> catches the error
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2034 and returns a status code.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2035 Its first result is the status code (a boolean),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2036 which is true if the call succeeds without errors.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2037 In such case, <code>pcall</code> also returns all results from the call,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2038 after this first result.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2039 In case of any error, <code>pcall</code> returns <b>false</b> plus the error.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2040
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2041
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2043
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2044 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2045 <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	2046 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	2047 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	2048 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	2049 <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	2050 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	2051 for instance for debugging.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2052 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	2053 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	2054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2056
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2057 <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	2058
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2059 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2060 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	2061
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2062 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2063 Example use:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2064
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2065 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2066 for i in range(1,10) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2067 Io.print("count up:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2068 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2069 for i in range(10,0,-1) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2070 Io.print("count down:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2071 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2072 </pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2073
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2074 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2075 Could be defined as:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2076
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2077 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2078 function Luan.range(start, stop, step)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2079 step = step or 1
478 eb6d90fb0b5c documentation Franklin Schmidt <fschmidt@gmail.com> parents: 476 diff changeset	2080 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	2081 local i = start
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2082 return function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2083 if step > 0 and i <= stop or step < 0 and i >= stop then
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2084 local rtn = i
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2085 i = i + step
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2086 return rtn
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2087 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2088 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2089 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2090 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2091
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2092
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2093
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2094 <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	2095
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2096 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2097 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	2098 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2099 Returns a boolean.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2100
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2101
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: 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.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	2104
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2105 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2106 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	2107 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2108 <code>table</code> must be a table;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2109 <code>index</code> may be any value.
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2113 <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	2114
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2115 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2116 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	2117 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	2118 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2119 Returns an integer.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2122
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2123 <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	2124
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2125 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2126 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	2127 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2128 <code>table</code> must be a table,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2129 <code>index</code> any value different from <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2130 and <code>value</code> any Lua value.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2131
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2132
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2133 <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	2134
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2135 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2136 Sets the metatable for the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2137 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	2138 removes the metatable of the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2139 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	2140 raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2141
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2142
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2143
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2144 <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	2145
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2146 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2147 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	2148 converts it to a string in a human-readable format.
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2149
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2150 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2151 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	2152 then <code>to_string</code> calls the corresponding value
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2153 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	2154 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	2155
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2157
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2158 <h4 heading><a name="Luan.try" href="#Luan.try"><code>Luan.try (t, ···)</code></a></h4>
589 97c8ae330efe add varargs to Luan.try; Franklin Schmidt <fschmidt@gmail.com> parents: 581 diff changeset	2159
97c8ae330efe add varargs to Luan.try; Franklin Schmidt <fschmidt@gmail.com> parents: 581 diff changeset	2160 <p>
97c8ae330efe add varargs to Luan.try; Franklin Schmidt <fschmidt@gmail.com> parents: 581 diff changeset	2161 Implements try-catch as found in other languages where each block is in table <code>t</code>. <code>t[1]</code> is the "try" block. The <code>t.catch</code> and <code>t.finally</code> blocks are optional. Any extra arguments are passed to the "try" function. Returns the result of the "try" block or the "catch" block.
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2162
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2163 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2164 Example use:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2165
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2166 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2167 try {
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2168 function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2169 a_dangerous_fn()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2170 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2171 catch = function(e)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2172 -- handle error
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2173 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2174 finally = function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2175 -- clean up
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2176 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2177 }
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2178 </pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2179
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2180 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2181 Could be defined as:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2182
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2183 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2184 function Luan.try(t)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2185 local r = { <a href="#Luan.pcall">Luan.pcall</a>(t[1]) }
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2186 if r[1] then
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2187 Table.remove(r,1)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2188 elseif t.catch ~= nil then
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2189 r = { t.catch(r[2]) }
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2190 else
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2191 t.finally and t.finally()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2192 r[2].throw()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2193 end
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2194 t.finally and t.finally()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2195 return Table.unpack(r)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2196 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2197 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2198
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 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="Luan.type" href="#Luan.type"><code>Luan.type (v)</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2201
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2202 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2203 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	2204 The possible results of this function are
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2205 "<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	2206 "<code>number</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2207 "<code>string</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2208 "<code>binary</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2209 "<code>boolean</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2210 "<code>table</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2211 "<code>function</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2212 and "<code>java</code>".
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2213
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2214
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2215 <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	2216
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2217 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2218 Returns a function so that the construction
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2219
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2220 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2221 for v in Luan.values(···) do <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2222 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2223
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2224 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2225 will iterate over all values of <code>···</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2226
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2227
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2228
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2229 <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	2230
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2231 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2232 A global variable (not a function) that
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2233 holds a string containing the current interpreter version.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2234 The current value of this variable is "<code><%=Luan.VERSION%></code>".
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2235
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2236
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2237
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2238
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2239
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2240
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2241 <h3 heading><a name="package_lib">Modules</a></h3>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2242
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2243 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2244 Include this library by:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2245
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2246 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2247 local Package = require "luan:Package.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2248 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2249
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2250 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2251 The package library provides basic
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2252 facilities for loading modules in Luan.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2253
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2254
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2255 <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	2256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2257 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2258 Loads the given module.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2259 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	2260 to determine whether <code>mod_uri</code> is already loaded.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2261 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	2262 at <code>Package.loaded[mod_uri]</code>.
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2263 Otherwise, it tries to load a new value for the module.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2264
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2265 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2266 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	2267
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2268 <p>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2269 If <code>mod_uri</code> is not a Java class, then <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>nil</b>. If the file exists, then its content is compiled into a chunk calling <a href="#Luan.load"><code>Luan.load</code></a> and passing in an empty table as the <code>env</code> value. This chunk is run passing in <code>mod_uri</code> as an argument. If the chunk returns a value other than <b>nil</b>, then that value is the value of this module. Otherwise the <code>env</code> that was passed in is the value of this module.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2270
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2271 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2272 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	2273
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2274
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2275
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2276
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2277 <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	2278
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2279
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2280 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2281 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	2282 modules are already loaded.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2283 When you load a module <code>mod_uri</code> and
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2284 <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	2285 <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	2286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2288 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2289 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	2290 assignments to this variable do not change the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2291 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	2292
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2293
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2294
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2295
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2296
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2297
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2298 <h3 heading><a name="string_lib">String Manipulation</a></h3>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2299
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2300 <p>
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2301 Include this library by:
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2302
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2303 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2304 local String = require "luan:String.luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2305 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2306
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2307 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2308 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	2309 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	2310 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	2311 (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	2312 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	2313 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	2314 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	2315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2317
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2318 <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	2319
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2320 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2321 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	2322 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	2323 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	2324 to its corresponding argument.
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2327 <h4 heading><a name="String.concat" href="#String.concat"><code>String.concat (···)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2328
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2329 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2330 Concatenates the <a href="#Luan.to_string"><code>to_string</code></a> value of all arguments.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2331
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2332
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2333
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2334 <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	2335
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2336 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2337 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	2338
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2339
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2340
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2341
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2342 <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	2343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2344 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2345 Looks for the first match of
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2346 <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	2347 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	2348 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	2349 otherwise, it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2350 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	2351 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	2352 its default value is 1 and can be negative.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2353 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	2354 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	2355 so the function does a plain "find substring" operation,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2356 with no characters in <code>pattern</code> being considered magic.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2357 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	2358
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2359 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2360 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	2361 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	2362 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	2363 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2365
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.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	2369
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2370
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2371 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2372 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	2373 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	2374 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	2375
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2376 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2377 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	2378
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2379
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2380
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2381 <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	2382
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2383 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2384 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	2385 each time it is called,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2386 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	2387 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2388 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	2389 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	2390
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2391
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2392 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2393 As an example, the following loop
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2394 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	2395 printing one per line:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2396
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2397 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2398 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2399 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2400 print(w)
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2401 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2402 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2403
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2404 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2405 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	2406 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	2407
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2408 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2409 local t = {}
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2410 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2411 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	2412 t[k] = v
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2413 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2414 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2415
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2416 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2417 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	2418 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	2419
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2420
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: 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.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	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 a copy of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2426 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	2427 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	2428 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	2429 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	2430 <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	2431 the total number of matches that occurred.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2432 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	2433
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2434
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2435 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2436 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	2437 The character <code>\</code> works as an escape character.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2438 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	2439 with <em>d</em> between 1 and 9,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2440 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	2441 The sequence <code>$0</code> stands for the whole match.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2442
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2443
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2444 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2445 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	2446 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	2447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2448
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2449 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2450 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	2451 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	2452 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2453
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2455 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2456 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2457 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	2458 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	2459
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2460
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2461 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2462 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	2463 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	2464 then it is used as the replacement string;
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2465 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	2466 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	2467 (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	2468
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2469
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2470 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2471 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2472
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2473 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2474 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	2475 --> 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	2476
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2477 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	2478 --> x="hello hello world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2479
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2480 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	2481 --> x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2482
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2483 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	2484 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2485 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2486 --> x="4+5 = 9"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2487
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2488 local t = {name="lua", version="5.3"}
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2489 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	2490 --> x="lua-5.3.tar.gz"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2491 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2492
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2493
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2494
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2495 <h4 heading><a name="String.literal" href="#String.literal"><code>String.literal (s)</code></a></h4>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2496 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2497 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>.
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2500 <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	2501 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2502 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	2503 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	2504 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	2505
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2507
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2508
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2509 <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	2510
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2511 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2512 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2513 <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	2514 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	2515 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	2516 otherwise it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2517 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	2518 then the whole match is returned.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2519 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	2520 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	2521 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	2522
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: 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="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	2525 <p>
629 35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2526 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	2527 This function is equivalent to
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2528
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2529 <pre>
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2530 return String.match(s,pattern) ~= nil
35dde32c02ab change String.matches() Franklin Schmidt <fschmidt@gmail.com> parents: 626 diff changeset	2531 </pre>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2532
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2533
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2534 <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	2535 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2536 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	2537 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	2538 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	2539 (that is, no separator).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2540 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	2541
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2542
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2543
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2544
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2545 <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	2546 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2547 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	2548
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2549
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2550
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2551
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2552 <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	2553
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2554 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2555 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2556 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	2557 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2558 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	2559 (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	2560 In particular,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2561 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	2562 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2563 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	2564 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	2565
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2566
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2567 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2568 If, after the translation of negative indices,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2569 <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	2570 it is corrected to 1.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2571 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	2572 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	2573 If, after these corrections,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2574 <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	2575 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	2576
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2577
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2578
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2579 <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	2580
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2581 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2582 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	2583
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2584
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2585
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2586 <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	2587
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2588 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2589 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2590 <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	2591 If the argument is
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2592 a string convertible to a number,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2593 then <code>to_number</code> returns this number;
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2594 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2595
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2596 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2597
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2598
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2599 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2600 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2601 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	2602 an integer numeral in that base.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2603 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	2604 represents 10, '<code>B</code>' represents 11, and so forth,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2605 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2606 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	2607 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2608
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2609
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2610
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2611 <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	2612
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2613 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2614 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	2615
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2616
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2617
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2618
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2619 <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	2620
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2621 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2622 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	2623 <code>s[i+1]</code>, ..., <code>s[j]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2624 The default value for <code>i</code> is 1;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2625 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	2626 These indices are corrected
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2627 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	2628
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2629
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2630
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2631
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2632
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2633 <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	2634 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2635 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	2636 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	2637 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	2638 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	2639
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2640
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2641
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2642
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2643
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2644 <h3 heading><a name="binary_lib">Binary Manipulation</a></h3>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2645
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2646 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2647 Include this library by:
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2648
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2649 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2650 local Binary = require "luan:Binary.luan"
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2651 </pre>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2652
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2653
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2654 <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	2655
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2656 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2657 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2658 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2659 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2660 to its corresponding argument.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2661
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2662
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2663 <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	2664
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2665 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2666 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2667 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2668 The default value for <code>i</code> is 1;
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2669 the default value for <code>j</code> is <code>i</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2670 These indices are corrected
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2671 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	2672
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2673
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2674 <h4 heading><a name="Binary.to_string" href="#Binary.to_string"><code>Binary.to_string (b)</code></a></h4>
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2675 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2676 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[])">String constructor</a>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2677
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2678
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2679
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2680
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2681 <h3 heading><a name="table_lib">Table Manipulation</a></h3>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2682
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2683 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2684 Include this library by:
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2685
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2686 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2687 local Table = require "luan:Table.luan"
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2688 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2690 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2691 This library provides generic functions for table manipulation.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2692 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2693
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2694
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2695
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2696 <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	2697
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2698 <p>
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2699 Clears the table.
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2700
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2701
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2702 <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	2703
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2704 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2705 Given a list,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2706 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	2707 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	2708 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	2709 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	2710 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	2711
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2712
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2713 <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	2714
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2715 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2716 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	2717 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	2718 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2719
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2720
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2721
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2722 <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	2723
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2724 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2725 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	2726 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2727 <code>list[pos], list[pos+1], ···, list[#list]</code>.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2728
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2729
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 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="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	2732
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2733 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2734 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	2735 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	2736 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	2737
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2738
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2741 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2745 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	2746 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	2747 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	2748 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	2749 <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	2750 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	2751 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	2752 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	2753 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	2754
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2755
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2756
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2757
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2758 <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	2759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2760 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2761 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	2762 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	2763 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	2764 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	2765 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	2766 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	2767 (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	2768 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	2769 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	2770
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2771 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2772 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	2773 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	2774 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	2775
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2776
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2777
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2778 <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	2779
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2780 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2781 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	2782 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	2783
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2784 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2785 return list[i], list[i+1], ···, list[j]
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2786 </pre>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2787
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2788 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2789 By default, <code>i</code> is 1 and <code>j</code> is <code>#list</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2790
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2791
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2792
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2793
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2794 <h3 heading><a name="number_lib">Number Manipulation</a></h3>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2795
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2796 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2797 Include this library by:
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2798
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2799 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2800 local Number = require "luan:Number.luan"
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2801 </pre>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2802
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2803
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2804 <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	2805 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2806 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2807
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2808
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2809 <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	2810 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2811 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	2812 returns that integer.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2813 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2814
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2815
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2816 <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	2817 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2818 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	2819 returns that long.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2820 Otherwise throws an error.
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="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	2824 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2825 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	2826
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2827
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2828 <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	2829 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2830 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	2831
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2832
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2833
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2834
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2835 <h3 heading><a name="math_lib">Mathematical Functions</a></h3>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2836
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2837 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2838 Include this library by:
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 <pre>
693 ca169567ce07 module URIs must now include ".luan" Franklin Schmidt <fschmidt@gmail.com> parents: 685 diff changeset	2841 local Math = require "luan:Math.luan"
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2842 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2843
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2844 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2845 This library provides basic mathematical functions.
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2846 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	2847
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 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.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	2850
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2851 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2852 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	2853
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2856 <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	2857
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2858 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2859 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	2860
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2864 <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	2865
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2866 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2867 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	2868
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2869
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2870
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2871
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2872 <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	2873
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2874 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2875 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	2876 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	2877 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2878 (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	2879
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2880
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2881
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2882
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2883 <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	2884
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2885 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2886 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	2887
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2888
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2889
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2890
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2891 <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	2892
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2893 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2894 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	2895
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2896
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2897
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2898
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2899 <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	2900
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2901 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2902 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	2903
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2904
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2905
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2906
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2907 <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	2908
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2909 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2910 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	2911 (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	2912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2913
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2914
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2915
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2916 <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	2917
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2918 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2919 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	2920
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2921
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2922
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2923
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2924 <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	2925
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2926 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2927 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	2928 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2929
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2930
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2931
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2932
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2933 <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	2934
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2935 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2936 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	2937
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2938
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2939
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2940
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2941 <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	2942
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2943 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2944 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	2945 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	2946 (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	2947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2948
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2951 <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	2952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2953 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2954 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	2955 according to the Lua operator <code><</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2956
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2957
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2958
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2959
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2960 <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	2961 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2962 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	2963
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2964
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2965
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2966
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2967 <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	2968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2969 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2970 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	2971 according to the Lua operator <code><</code>.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2972
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2973
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2974
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2975
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2976 <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	2977 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2978 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	2979
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2980
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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2983 <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	2984
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2985 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2986 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	2987
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2988
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2989
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2990
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2991 <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	2992
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2993 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2994 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	2995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2996
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2997
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2998
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	2999 <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	3000
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3001 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3002 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	3003
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3004
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3005
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3006
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	3007 <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	3008
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3009
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3010 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3011 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3012 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	3013 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	3014 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	3015 <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	3016 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	3017 (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	3018 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	3019
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3020
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3021 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3022 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	3023 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	3024 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	3025
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3026
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3027
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3028
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	3029 <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	3030
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3031 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3032 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	3033
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3034
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3035
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3036
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	3037 <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	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 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	3041 (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	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
642 c4216a583de4 add links to functions in manual Franklin Schmidt <fschmidt@gmail.com> parents: 629 diff changeset	3046 <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	3047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3048 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3049 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	3050
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3051
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3052
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3053
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3054
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3058 <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	3059
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3060 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3061 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	3062 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	3063 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	3064 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3065 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	3066 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	3067
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3068
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3069 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3070 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	3071 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	3072 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	3073 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	3074 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	3075
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3076
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3077 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3078 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	3079 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	3080 <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	3081 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3085 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3086 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	3087 (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	3088 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	3089 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	3090 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3091 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	3092 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3093 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	3094 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	3095
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3096
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3097 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3098 <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	3099
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3102 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	3103 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	3104
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3105
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3106
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3107
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3108 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3109 <hr><h3><a name="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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3113 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	3114
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3115
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3116
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 <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	3120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3122 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3123 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	3124 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	3125 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	3126 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	3127 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3128 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	3129
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3130
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3131 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3132 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	3133 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	3134
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3139 <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	3140
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3141
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3142 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3143 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	3144 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	3145 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	3146 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	3147 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	3148
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3149
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3150 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3151 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	3152 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	3153 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	3154 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	3155
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3157 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3158 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	3159 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	3160
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3161
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3162
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3163
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3164 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3165 <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	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 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	3170 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	3171 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	3172 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	3173
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3176 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	3177
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3178 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3179 <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	3180 <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	3181 <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	3182 <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	3183 <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	3184 <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	3185 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	3186 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3187 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	3188 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	3189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3190
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3191
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3192
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3193 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3194 <hr><h3><a name="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	3195
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3197 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3198 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	3199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3200
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3201
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3202
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3203 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3204 <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	3205
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3207 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3208 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	3209 on all platforms.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3210
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3211
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3212 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3213 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	3214 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	3215 (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	3216 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	3217 (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	3218
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3220
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3221
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3222 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3223 <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	3224
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3227 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	3228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3229
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3230
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3231
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3232 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3233 <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	3234
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3235
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3236 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3237 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	3238 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	3239 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	3240
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3241
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3242
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3244 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3245 <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	3246
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3247
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3248 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3249 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	3250 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	3251 <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	3252 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	3253
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3254
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3255
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3257 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3258 <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	3259
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3260
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3261 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3262 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	3263
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3264
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3265
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3266
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3267 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3268 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3272 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3273 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	3274 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	3275 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	3276
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3277
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3278 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3279 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	3280 <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	3281 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	3282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3284
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3285
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3286 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3287 <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	3288
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3289
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3290 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3291 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3295
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3296 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3297 <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	3298
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3299
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3300 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3301 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	3302 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	3303 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	3304 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	3305 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	3306 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	3307
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3308 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3309 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	3310 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3311 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	3312 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	3313 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	3314 when the loop ends.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3317 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3318 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	3319 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	3320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3321
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3322
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3323
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3324 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3325 <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	3326
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3327
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3328 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3329 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	3330 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	3331 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3332 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	3333 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	3334 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3335 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	3336 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3337 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	3338 (see below).
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 The available formats are
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3345
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3346 <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	3347 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	3348 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	3349 (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	3350 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	3351 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	3352 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	3353 (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	3354 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	3355 </li>
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 <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	3358 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	3359 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3360
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3361 <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	3362 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	3363 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	3364 </li>
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 <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	3367 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	3368 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	3369 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	3370 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3372 <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	3373 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	3374 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	3375 </li>
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 <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	3378 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	3379 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	3380 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	3381 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	3382 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	3383 </li>
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 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3386 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	3387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3388
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3389
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3390
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3391 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3392 <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	3393
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3394
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3395 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3396 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	3397 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	3398 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	3399 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	3400
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3401 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3402 <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	3403 <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	3404 <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	3405 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3406 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	3407 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	3408 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	3409 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	3410
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3412 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3413 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	3414 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	3415 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	3416 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	3417 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	3418 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	3419 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	3420 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	3421
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3422
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3423
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3424
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3425 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3426 <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	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 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	3431 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	3432
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3433 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3434
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3435 <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	3436 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	3437 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3438
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3439 <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	3440 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	3441 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	3442 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	3443 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3444
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3445 <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	3446 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	3447 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	3448 (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	3449 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3450
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3451 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3452 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	3453 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	3454 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	3455
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3458
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3459 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3460 <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	3461
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3462
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3463 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3464 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	3465 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	3466
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3467
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3468 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3469 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	3470 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	3471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3472
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3473
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 <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	3479
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3480 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3481 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	3482
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3483
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3484 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3485 <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	3486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3487
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3488 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3489 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	3490 used by the program.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3494
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3495 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3496 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3500 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	3501 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	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 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	3506 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	3507 (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	3508 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	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 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	3513 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	3514 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3515 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	3516 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	3517 <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	3518 <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	3519 <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	3520 <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	3521 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	3522 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	3523 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	3524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3525
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3526 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3527 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	3528 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	3529 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	3530
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3531
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3532 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3533 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3534 <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	3535 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	3536 (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	3537
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3540 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3541 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	3542 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	3543
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3544
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3545
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3546
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3547 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3548 <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	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 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	3553 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	3554 (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	3555 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	3556 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	3557
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3558
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3559
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3560
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3561 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3562 <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	3563
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3564
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3565 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3566 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	3567 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	3568 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	3569 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	3570 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	3571 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3572 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	3573 as follows:
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3576
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3577 <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	3578 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3579 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	3580 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3581
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3582 <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	3583 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	3584 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	3585 </li>
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 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3588
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3589 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3590 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	3591 <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	3592
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3594
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3597 <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	3598
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3599
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3600 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3601 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	3602 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	3603 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	3604 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	3605 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	3606 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	3607 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	3608 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	3609
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3610
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3611 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3612 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	3613 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	3614
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3615
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3616
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3617
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3618 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3619 <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	3620
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3621
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3622 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3623 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	3624 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3630 <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	3631
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 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	3635 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3636 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	3637 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	3638
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3639
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3640
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3641
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3642 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3643 <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	3644
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3647 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	3648 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	3649 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	3650
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3651
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3652
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3653
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3654 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3655 <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	3656
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3657
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3658 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3659 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	3660 <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	3661 <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	3662 <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	3663 <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	3664 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	3665 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	3666 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	3667
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3670 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	3671 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	3672 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	3673 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3677 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	3678 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	3679 for the given category.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3682 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3683 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	3684 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	3685
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3690 <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	3691
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3694 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	3695 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	3696 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	3697 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3698 <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	3699 <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	3700 <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	3701 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	3702 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	3703
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3704
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3705 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3706 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	3707 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	3708 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	3709 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	3710 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	3711 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	3712 <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	3713
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3714
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3715
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3716
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3717 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3718 <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	3719
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3722 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	3723 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	3724 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	3725 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	3726
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3727
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3728 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3729 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3730 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	3731 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3732 (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	3733 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	3734 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	3735 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	3736
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3737
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3738 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3739 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3740 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	3741 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3745
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3746
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3747
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3748
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3749 <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	3750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3751 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3752 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3753 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	3754 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	3755 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3756 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	3757 (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	3758 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	3759 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	3760 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	3761 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	3762 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	3763
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3764
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3765 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3766 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	3767 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	3768 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	3769 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	3770 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3771 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	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 <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	3776
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3779 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	3780 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	3781 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	3782 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	3783 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	3784 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	3785 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	3786
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3789 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	3790 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	3791
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3792
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 <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	3797
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3798
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3799 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3800 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	3801 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	3802 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	3803 (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	3804
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3809 <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	3810
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3813 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	3814 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	3815 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	3816 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	3817 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3818 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	3819 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	3820 (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	3821 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3822 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	3823 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	3824
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3825
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3826 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3827 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	3828 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	3829 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	3830 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	3831 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3832 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	3833 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	3834 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3835 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	3836 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	3837 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3838
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3839
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3840 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3841 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	3842 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	3843 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	3844 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	3845 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	3846 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	3847
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3848
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3849
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3850
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3851 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3852 <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	3853
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3854
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3855 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3856 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	3857 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	3858 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	3859 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3863 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	3864 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	3865 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	3866 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	3867 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	3868 -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	3869 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	3870 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	3871 (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	3872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3873
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3874 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3875 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	3876 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	3877 (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	3878 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	3879
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3880
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3881 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3882 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	3883 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	3884
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3885
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3886
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3889 <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	3890
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3891
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3892 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3893 Returns 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	3894 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3898
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3899 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3900 <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	3901
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3902
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3903 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3904 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	3905
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3906
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3907
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3910 <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	3911
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3913 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3914 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	3915 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	3916 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	3917
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3918
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3919 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3920 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	3921 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	3922 (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	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.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	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 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	3933 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	3934 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3935
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3936
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3939 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3940 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3944 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	3945 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	3946 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	3947 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	3948 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3949
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3950 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3951 <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	3952 <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	3953 <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	3954 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3955 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3956 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	3957 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	3958
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3959
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3960 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3961 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3962 <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	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 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	3967 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	3968 <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	3969 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3970 <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	3971 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3972 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	3973 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3974 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	3975 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3976 (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	3977 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	3978
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3979
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3982 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3983 <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	3984
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3986 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3987 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	3988 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	3989 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	3990 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	3991 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	3992 (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	3993 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	3994
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3996 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3997 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	3998 variable indices and names.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3999
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4000
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4001
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4002
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4003 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4004 <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	4005
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4006
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4007 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4008 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	4009 (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	4010 Returns <code>value</code>.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4014
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4015 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4016 <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	4017
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4018
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4019 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4020 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	4021 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	4022 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	4023 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4024 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	4025
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4026
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4027
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4029 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4030 <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	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 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	4035 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	4036 <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	4037
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4038
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4039 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4040 Returns <code>udata</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4041
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4043
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4044
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 <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	4047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4048
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4049 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4050 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	4051 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	4052 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4053 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	4054 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	4055 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	4056 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	4057 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4058 (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	4059
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4060
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4063 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4064 <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	4065
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4066
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4067 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4068 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	4069 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	4070 from the given function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4073 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4074 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	4075 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4076 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	4077 (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	4078 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	4079
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4080
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 <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	4085
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4086
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4087 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4088 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	4089 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	4090
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4091
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4092
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4093
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4094
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4095
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4096
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4097 <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	4098
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4099 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4100 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	4101 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	4102 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	4103 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	4104 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	4105 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	4106 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4107 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	4108 Its usage is:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4109
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4110 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4111 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4112 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4113 The options are:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4114
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4115 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4116 <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	4117 <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	4118 <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	4119 <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	4120 <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	4121 <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	4122 <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	4123 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4124 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	4125 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4126 <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	4127 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	4128 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	4129
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4130
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4131 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4132 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	4133 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	4134 (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	4135 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4136 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	4137 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	4138 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	4139
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4140
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4141 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4142 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	4143 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	4144 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4145 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	4146 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4147 <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	4148 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	4149
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4150
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4151 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4152 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	4153 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	4154
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4155 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4156 $ 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	4157 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4158 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	4159 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	4160 (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	4161
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4162
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4163 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4164 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4165 <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	4166 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	4167 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	4168 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	4169 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4170 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	4171 (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	4172 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4173 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	4174
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4175 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4176 $ 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	4177 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4178 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	4179
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4180 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4181 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	4182 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4183 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4184 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4185 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	4186 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	4187 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	4188 For instance, the call
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4190 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4191 $ 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	4192 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4193 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	4194 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	4195 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	4196 <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	4197 (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	4198 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	4199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4200
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4201 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4202 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4203 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	4204 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4205 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	4206 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	4207 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	4208 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	4209 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	4210 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	4211
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4212
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4213 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4214 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	4215 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	4216 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	4217 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	4218 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	4219 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	4220 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	4221
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4222
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4223 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4224 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4225 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	4226 (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	4227 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	4228 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	4229
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4230
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4231 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4232 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	4233 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	4234 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4235 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	4236 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	4237 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	4238 as in
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4239
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4240 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4241 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4242 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4243 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4244 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	4245 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	4246 then
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4249 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4250 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4251 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	4252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4253
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4254
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4255 <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	4256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4257 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4258 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	4259 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	4260 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	4261 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	4262 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4263 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	4264
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4265
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4266 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4267 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	4268 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	4269 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	4270 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	4271 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4272 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	4273 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4274 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	4275 using a new version.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4278 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4279 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	4280 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4281 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	4282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4285 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	4286 change between versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4287
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4290 <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	4291 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4292
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4293 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4294 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	4295 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	4296 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	4297 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4298 (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	4299 can give different results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4300
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4303 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	4304 (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	4305 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	4306 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	4307 (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	4308 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4309 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	4310 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4311 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	4312 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	4313 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4316 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	4317 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	4318 (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	4319 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	4320 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	4321 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	4322
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4323
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4324 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4325 (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	4326 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	4327 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	4328 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4331 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	4332 (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	4333 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4334
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4335 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4336
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4338
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4339
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4340 <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	4341 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4342
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4343 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4344 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	4345 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	4346 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	4347 (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	4348 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	4349 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4351 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4352 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	4353 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	4354 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4357 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	4358 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	4359 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4360
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4361 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4362 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	4363 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	4364 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4367 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	4368 <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	4369 <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	4370 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	4371 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	4372 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	4373 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	4374 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4375 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	4376 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4377 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4380 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	4381 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	4382 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	4383 (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	4384 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	4385 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	4386 (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	4387 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	4388 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4389
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4390 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4391
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4393
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4394
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4395 <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	4396
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 <ul>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4401 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	4402 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	4403 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	4404 Adapt your code accordingly.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4405 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4408 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	4409 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	4410 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4412 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4413 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	4414 (<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	4415 <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	4416 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4417 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	4418 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4419
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4420 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4421 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	4422 (<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	4423 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4424 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	4425 (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	4426 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4427
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4428 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4429
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4430
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4431
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4432
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4433 <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	4434
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4435 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4436 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	4437 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	4438 {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	4439 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	4440 (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	4441 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	4442 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4443 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	4444
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4445
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4448 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4449
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4450 chunk ::= block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4451
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4452 block ::= {stat} [retstat]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4453
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4454 stat ::= ‘<b>;</b>’ \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4455 varlist ‘<b>=</b>’ explist \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4456 functioncall \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4457 label \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4458 <b>break</b> \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4459 <b>goto</b> Name \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4460 <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	4461 <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	4462 <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	4463 <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	4464 <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	4465 <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	4466 <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	4467 <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	4468 <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	4469
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4470 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	4471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4472 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	4473
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4474 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	4475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4476 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	4477
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4478 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	4479
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4480 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	4481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4482 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	4483
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4484 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	4485 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	4486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4487 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	4488
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4489 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	4490
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4491 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	4492
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4493 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	4494
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4495 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	4496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4497 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	4498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4499 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	4500
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4501 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	4502
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4503 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	4504
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4505 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	4506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4507 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	4508 ‘<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	4509 ‘<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	4510 <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	4511
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4512 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	4513
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4514 </pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4515
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4516 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4517
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4518
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4520
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4521
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4522
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4523
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4525 <HR>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4526 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4527 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4528 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	4529 </SMALL>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4530 <!--
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4531 Last change: minor edit
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4532 -->
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4533
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	4534 </div>
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	4535
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	4536 </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	4537 </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	4538 <%
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	4539 end

Mercurial Hosting > luan

annotate website/src/manual.html.luan @ 695:5042e487d717