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

annotate website/src/manual.html.luan @ 583:1368ca798ccc

add Http.uncache_site

author	Franklin Schmidt <fschmidt@gmail.com>
date	Fri, 31 Jul 2015 19:19:42 -0600
parents	5d4652d78ce0
children	97c8ae330efe

rev	line source
478 eb6d90fb0b5c documentation Franklin Schmidt <fschmidt@gmail.com> parents: 476 diff changeset	1 local Luan = require "luan:Luan"
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	2 local Io = require "luan:Io"
db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	3 local Html = require "luan:Html"
494 2b9bc97f0439 change luan:web to luan:http Franklin Schmidt <fschmidt@gmail.com> parents: 492 diff changeset	4 local Http = require "luan:http/Http"
387 23d075ce1e48 add website/src/Shared.luan Franklin Schmidt <fschmidt@gmail.com> parents: 386 diff changeset	5 local Shared = require "site:/Shared"
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
502 d3183a330ff5 improve the __index metamethod to work with any type; Franklin Schmidt <fschmidt@gmail.com> parents: 495 diff changeset	475 <li><p><b>"call": </b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	476 The call operation <code>func(args)</code>.
373 571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	477
571057b1666b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 372 diff changeset	478 This event happens when Luan tries to call a table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	479 The metamethod is looked up in <code>func</code>.
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	480 If present,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	481 the metamethod is called with <code>func</code> as its first argument,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	482 followed by the arguments of the original call (<code>args</code>).
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	483 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	484
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	485 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	487
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	488
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	489
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	490 <h3 heading><a name="gc">Garbage Collection</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	491
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	492 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	493 Luan uses Java's garbage collection.
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	494
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	495
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	496
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	497
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	498
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	499 <h2 heading><a name="lang">The Language</a></h2>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	500
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	501 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	502 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	503 In other words,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	504 this section describes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	505 which tokens are valid,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	506 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	507 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	508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	510 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	511 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	512 in which
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	513 {<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	514 [<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	515 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	516 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	517 and other terminal symbols are shown like ‘<b>=</b>’.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	518 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	519 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	520
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	521
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	522
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	523 <h3 heading><a name="lex">Lexical Conventions</a></h3>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	524
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	525 <p>
6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	526 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	527 between lexical elements (tokens),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	528 except as delimiters between names and keywords.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	529 Luan generally considers the end of a line to be the end of a statement. This catches errors and encourages readability. The exception to this is in paranthesis ( <em>(...)</em>, <em>[...]</em>, and <em>{...}</em> ) where the end of line is treated as white space.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	530
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	531 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	532 <em>Names</em>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	533 (also called <em>identifiers</em>)
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	534 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	535 digits, and underscores,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	536 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	537 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	538
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	539
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	540 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	541 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	542 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	543
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	544
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	545 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	546 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	547 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	548 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	549 then true until while
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	550 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	551
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	552 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	553 Luan is a case-sensitive language:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	554 <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	555 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	556
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	557
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	558 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	559 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	560
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	561 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	562 + - * / % ^ #
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	563 & ~ \| << >> //
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	564 == ~= <= >= < > =
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	565 ( ) { } [ ] ::
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	566 ; : , . .. ...
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	567 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	568
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	569 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	570 <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	571 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	572 and can contain the following C-like escape sequences:
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	573 '<code>\a</code>' (bell),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	574 '<code>\b</code>' (backspace),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	575 '<code>\f</code>' (form feed),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	576 '<code>\n</code>' (newline),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	577 '<code>\r</code>' (carriage return),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	578 '<code>\t</code>' (horizontal tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	579 '<code>\v</code>' (vertical tab),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	580 '<code>\\</code>' (backslash),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	581 '<code>\"</code>' (quotation mark [double quote]),
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	582 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	583 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	584 results in a newline in the string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	585 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	586 of white-space characters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	587 including line breaks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	588 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	589 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	590 into the string contents.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	591
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 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	594 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	595 This can be done
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	596 with the escape sequence <code>\x<em>XX</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	597 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	598 or with the escape sequence <code>\<em>ddd</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	599 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	600 (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	601 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	602
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	603
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	604 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	605 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	606 enclosed by <em>long brackets</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	607 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	608 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	609 opening square bracket.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	610 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	611 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	612 and so on.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	613 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	614 for instance,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	615 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	616 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	617 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	618 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	619 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	620 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	621 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	622 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	623 (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	624 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	625 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	626
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 <p>
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	629 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	630 explicitly affected by the previous rules represents itself.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	631 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	632 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	633 some control characters.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	634 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	635 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	636 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	637
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	638
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	639 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	640 For convenience,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	641 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	642 the newline is not included in the string.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	643 As an example
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	644 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	645
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	646 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	647 a = 'alo\n123"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	648 a = "alo\n123\""
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	649 a = '\97lo\10\04923"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	650 a = [[alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	651 123"]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	652 a = [==[
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	653 alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	654 123"]==]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	655 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	656
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	657 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	658 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	659 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	660 and an optional decimal exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	661 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	662 Luan also accepts hexadecimal constants,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	663 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	664 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	665 plus an optional binary exponent,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	666 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	667 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	668 denotes a float;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	669 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	670 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	671
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	672 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	673 3 345 0xff 0xBEBADA
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	674 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	675
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	676 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	677 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	678
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	679 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	680 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	681 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	682 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	683
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	684 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	685 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	686 anywhere outside a string.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	687 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	688 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	689 which runs until the end of the line.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	690 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	691 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	692 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	693
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	696
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	697
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	698 <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	699
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	700 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	701 Variables are places that store values.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	702 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	703 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	704
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	705 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	706 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	707 (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	708 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	709
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	710 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	711 var ::= Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	712 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	713
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	714 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	715 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	716
512 d96944467ffc update documentation for luan changes Franklin Schmidt <fschmidt@gmail.com> parents: 505 diff changeset	717 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	718 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	719 local variables can be freely accessed by functions
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	720 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	721
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	722
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	723 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	724 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	725
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	726 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	727 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	728
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	729 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	730 var ::= prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	731 </pre>
382 8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	732
8557581740db added tutorial Franklin Schmidt <fschmidt@gmail.com> parents: 380 diff changeset	733 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	734 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	735 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	736 a call <code>gettable_event(t,i)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	737 (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	738 <code>gettable_event</code> function.
380 6c6c3537035e work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 373 diff changeset	739 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	740 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	741
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	742
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	743 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	744 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	745 <code>var["Name"]</code>:
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 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	748 var ::= prefixexp ‘<b>.</b>’ Name
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	749 </pre>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	752 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	753 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	754 Due to the way that chunks are compiled,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	755 <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	756
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	757
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	758
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	759
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	760
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	761 <h3 heading><a name="stmts">Statements</a></h3>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	762
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	763 <p>
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	764 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	765 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	766 This set includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	767 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	768 and variable declarations.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	769
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	770
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	771
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	772 <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	773
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	774 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	775 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	776 which are executed sequentially:
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 block ::= {stat}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	780 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	781
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	782 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	783 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	784 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	785 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	786 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	787
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	788 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	789 stat ::= ‘<b>;</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	790 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	791
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	792 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	793 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	794
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	795 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	796 stat ::= <b>do</b> block <b>end</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	797 </pre>
389 497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	798
497d4ef0a89f documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 387 diff changeset	799 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	800 Explicit blocks are useful
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	801 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	802 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	803 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	804 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	805
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	806
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	807
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	809
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	810 <h4 heading><a name="chunks">Chunks</a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	811
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	812 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	813 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	814 Syntactically,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	815 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	816
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	817 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	818 chunk ::= block
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	819 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	820
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	821 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	822 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	823 with a variable number of arguments
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	824 (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	825 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	826 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	827
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	828
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	829 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	830 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	831 To execute a chunk,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	832 Luan first <em>loads</em> it,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	833 compiling the chunk's code,
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	834 and then Luan executes the compiled code.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	835
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	836
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	837
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	838
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	839
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	840 <h4 heading><a name="assignment">Assignment</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	841
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	842 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	843 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	844 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	845 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	846 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	847 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	848
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	849 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	850 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	851 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	852 explist ::= exp {‘<b>,</b>’ exp}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	853 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	854
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	855 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	856 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	857
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	858
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	859 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	860 Before the assignment,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	861 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	862 the list of variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	863 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	864 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	865 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	866 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	867 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	868 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	869 before the adjustment
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	870 (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	871
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	873 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	874 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	875 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	876 Thus the code
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	877
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	878 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	879 i = 3
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	880 i, a[i] = i+1, 20
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 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	885 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	886 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	887 Similarly, the line
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	888
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	889 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	890 x, y = y, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	891 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	892
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	893 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	894 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	895 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	896
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	897 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	898 x, y, z = y, z, x
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	899 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	900
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	901 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	902 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	903
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	906 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	907 and table fields can be changed via metatables.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	908 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	909 <code>settable_event(t,i,val)</code>.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	910 (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	911 <code>settable_event</code> function.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	912 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	913 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	914
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	915
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	916 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	917 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	918 is equivalent to the assignment
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	919 <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	920 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	921
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	922
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	923
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	924 <h4 heading><a name="control">Control Structures</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	925
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	926 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	927 The control structures
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	928 <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	929 familiar syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	930
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	931 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	932 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	933 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	934 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	935 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	936
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	937 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	938 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	939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	941 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	942 The condition expression of a
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	943 control structure must be a boolean.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	944 Any other value type will produce an error.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	945 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	946
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	948 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	949 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	950 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	951 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	952 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	953 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	954
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	955
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	956 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	957 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	958 <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	959 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	960
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	961
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	962 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	963 stat ::= <b>break</b>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	964 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	965
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	966 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	967 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	968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	970 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	971 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	972 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	973 (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	974
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	975 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	976 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	977
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	978 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	979 stat ::= <b>return</b> [explist] [‘<b>;</b>’]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	980 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	981
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	982
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	983
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	984
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	985 <h4 heading><a name="for">For Statement</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	986
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	987 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	988 The <b>for</b> statement works over functions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	989 called <em>iterators</em>.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	990 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	991 stopping when this new value is <b>nil</b>.
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	992 The <b>for</b> loop has the following syntax:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	993
562 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 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	996 namelist ::= Name {‘<b>,</b>’ Name}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	997 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	998
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	999 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1000 A <b>for</b> statement like
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1001
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1002 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1003 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	1004 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1005
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1006 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1007 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	1008
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1009 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1010 do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1011 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	1012 while true do
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1013 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	1014 if <em>var_1</em> == nil then break end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1015 <em>block</em>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1016 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1017 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1018 </pre>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1021 Note the following:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1023 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1024
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1025 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1026 <code><em>exp</em></code> is evaluated only once.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1027 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	1028 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1029
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1030 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1031 <code><em>f</em></code> is an invisible variable.
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1032 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	1033 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1034
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1035 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1036 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	1037 </li>
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 <li>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1040 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	1041 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	1042 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	1043 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	1044 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1045
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1046 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1048
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1049
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1050
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1051 <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	1052
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1053 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1054 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	1055 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	1056
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1057 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1058 stat ::= functioncall
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1059 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1060
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1061 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1062 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	1063 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	1064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1065
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1066
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1067 <h4 heading><a name="local_stmt">Local Declarations</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1068
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1069 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1070 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	1071 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	1072
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1073 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1074 stat ::= <b>local</b> namelist [‘<b>=</b>’ explist]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1075 </pre>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1076
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1077 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1078 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	1079 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	1080 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	1081
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1083 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1084 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	1085 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	1086
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1087
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1088 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1089 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	1090
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1091
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1092 <h4 heading><a name="template_stmt">Template Statements</a></h4>
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>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	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"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1098 %>
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>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1103
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1104 <p>is equivalent to the code:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1105
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1106 <pre><%=Html.encode[[
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1107 local name = "Bob"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1108 require("luan:Io").stdout.write( %>
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1109 Hello <%= name %>!
85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1110 Bye <%= name %>.
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1111 <% )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1112 ]]%></pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1113
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1114
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1115
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1116 <h3 heading><a name="expressions">Expressions</a></h3>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1117
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1118 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1119 The basic expressions in Luan are the following:
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1120
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1121 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1122 exp ::= prefixexp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1123 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	1124 exp ::= Numeral
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1125 exp ::= LiteralString
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1126 exp ::= functiondef
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1127 exp ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1128 exp ::= ‘<b>...</b>’
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1129 exp ::= exp binop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1130 exp ::= unop exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1131 prefixexp ::= var \| functioncall \| ‘<b>(</b>’ exp ‘<b>)</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1132 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1133
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1134 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1135 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	1136 variables are explained in <a href="#vars">Variables</a>;
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1137 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	1138 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	1139 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	1140 Vararg expressions,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1141 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	1142 directly inside a vararg function;
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1143 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	1144
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1145
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1146 <p>
eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1147 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	1148 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	1149 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	1150 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	1151 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	1152 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	1153
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1154
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1155 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1156 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	1157 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	1158 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	1159 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	1160 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	1161 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	1162 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	1163 (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	1164 In all other contexts,
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1165 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	1166 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	1167 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	1168
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1169
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1170 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1171 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1172
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1173 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1174 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	1175 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	1176 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	1177 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	1178 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	1179 -- 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	1180 -- 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	1181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1182 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	1183 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	1184 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	1185 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	1186 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	1187 {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	1188 {...} -- 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	1189 {f(), nil} -- f() is adjusted to 1 result
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1190 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1191
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1192 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1193 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	1194 Thus,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1195 <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	1196 even if <code>f</code> returns several values.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1197 (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	1198 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	1199
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1200
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1201
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1202 <h4 heading><a name="arithmetic">Arithmetic Operators</a></h4>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1203
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1204 <p>
a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1205 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	1206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1207 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1208 <li><b><code>+</code>: </b>addition</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1209 <li><b><code>-</code>: </b>subtraction</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1210 <li><b><code>*</code>: </b>multiplication</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1211 <li><b><code>/</code>: </b>division</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1212 <li><b><code>%</code>: </b>modulo</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1213 <li><b><code>^</code>: </b>exponentiation</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1214 <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	1215 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1217 <p>
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1218 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	1219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1220 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1221 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	1222 that rounds the quotient towards minus infinite (floor division).
395 a7cb58532846 work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 391 diff changeset	1223 (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	1224
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1226
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1227 <h4 heading><a name="conversions">Coercions and Conversions</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1228
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1229 <p>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1230 Luan generally avoids automatic conversions.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1231 String concatenation automatically converts all of its arguments to strings.
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1232
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1233 <p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1234 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	1235
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1236
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1237
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1238
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1239 <h4 heading><a name="relational">Relational Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1240
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1241 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1242 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	1243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1244 <ul>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1245 <li><b><code>==</code>: </b>equality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1246 <li><b><code>~=</code>: </b>inequality</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1247 <li><b><code><</code>: </b>less than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1248 <li><b><code>></code>: </b>greater than</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1249 <li><b><code><=</code>: </b>less or equal</li>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1250 <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	1251 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1252 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	1253
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1254
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1255 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1256 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	1257 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	1258 Otherwise, the values of the operands are compared.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1259 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	1260
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1261 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1262 Tables
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1263 are compared by reference:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1264 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	1265 Every time you create a new table,
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1266 it is different from any previously existing table.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1267 Closures are also compared by reference.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1268
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1269 <p>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1270 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	1271 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	1272
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1273 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1274 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	1275
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1276 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1277 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	1278 or vice versa.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1279 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1280 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	1281 entries in a table.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1284 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1285 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	1286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1288 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1289 The order operators work as follows.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1290
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1291 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	1292 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	1293 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	1294 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	1295 then their values are compared according to the current locale.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1296 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	1297 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1298 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	1299 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	1300
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1301
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1302
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1303
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1304
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1305 <h4 heading><a name="logical_ops">Logical Operators</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1306
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1307 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1308 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	1309 <b>and</b>, <b>or</b>, and <b>not</b>.
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1310 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	1311 and anything else as true.
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1312 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	1313 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	1314
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1315 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1316 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	1317 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	1318 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	1319 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	1320 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	1321 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	1322 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	1323 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	1324 that is,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1325 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	1326 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1327
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1328 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1329 10 or 20 --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1330 10 or error() --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1331 nil or "a" --> "a"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1332 nil and 10 --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1333 false and error() --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1334 false and nil --> false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1335 false or nil --> nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1336 10 and 20 --> 20
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1337 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1338
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1339 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1340 (In this manual,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1341 <code>--></code> indicates the result of the preceding expression.)
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1342
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1343
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1344
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1345 <h4 heading><a name="concatenation">Concatenation</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1346
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1347 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1348 The string concatenation operator in Luan is
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1349 denoted by two dots ('<code>..</code>').
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1350 All operands are converted to strings.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1351
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1352
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1353
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1354 <h4 heading><a name="length">The Length Operator</a></h4>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1357 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	1358 The length of a string is its number of characters.
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1359 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	1360
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1361
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1362 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1363 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	1364 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	1365
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1366
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1367 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1368 Unless a <code>__len</code> metamethod is given,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1369 the length of a table <code>t</code> is defined
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1370 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	1371 that is,
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1372 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	1373 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	1374 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	1375 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	1376
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1377 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1378 {10, 20, nil, 40}
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1379 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1380
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1381 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1382 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	1383
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1384
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1385
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1386
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1387
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1388 <h4 heading><a name="precedence">Precedence</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1389
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1390 <p>
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1391 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	1392 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	1393
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1394 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1395 or
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1396 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1397 < > <= >= ~= ==
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1398 ..
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1399 + -
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1400 * / %
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1401 unary operators (not # -)
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1402 ^
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1403 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1404
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1405 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1406 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1407 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	1408 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	1409 operators are right associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1410 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	1411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1412
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1413
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1415
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1416 <h4 heading><a name="constructors">Table Constructors</a></h4>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1417
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1418 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1419 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	1420 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	1421 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	1422 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	1423 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	1424
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1425 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1426 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	1427 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	1428 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	1429 fieldsep ::= ‘<b>,</b>’ \| ‘<b>;</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1430 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1431
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1432 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1433 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	1434 with key <code>exp1</code> and value <code>exp2</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1435 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	1436 <code>["name"] = exp</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1437 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	1438 <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	1439 starting with 1.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1440 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	1441 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1442
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1443 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1444 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	1445 </pre>
396 ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1446
ba8b0aae6453 work on manual; Franklin Schmidt <fschmidt@gmail.com> parents: 395 diff changeset	1447 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1448 is equivalent to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1449
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1450 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1451 do
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1452 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1453 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1454 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	1455 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	1456 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	1457 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	1458 t[30] = 23
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1459 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	1460 a = t
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1461 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1462 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1463
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1464 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1465 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	1466 (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	1467
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1468
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1469 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1470 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	1471 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	1472 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	1473 (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	1474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1476 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1477 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	1478 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	1479
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1482
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1483
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1484 <h4 heading><a name="fn_calls">Function Calls</a></h4>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1485
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1486 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1487 A function call in Luan has the following syntax:
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1488
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1489 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1490 functioncall ::= prefixexp args
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1491 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1492
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1493 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1494 In a function call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1495 first prefixexp and args are evaluated.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1496 If the value of prefixexp has type <em>function</em>,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1497 then this function is called
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1498 with the given arguments.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1499 Otherwise, the prefixexp "call" metamethod is called,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1500 having as first parameter the value of prefixexp,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1501 followed by the original call arguments
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1502 (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	1503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1504
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1505 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1506 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	1507
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1508 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1509 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	1510 args ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1511 args ::= LiteralString
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1512 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1513
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1514 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1515 All argument expressions are evaluated before the call.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1516 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	1517 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	1518 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	1519 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	1520 (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	1521 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	1522 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	1523
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1525 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1526 A call of the form <code>return <em>functioncall</em></code> is called
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1527 a <em>tail call</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1528 Luan implements <em>proper tail calls</em>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1529 (or <em>proper tail recursion</em>):
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1530 in a tail call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1531 the called function reuses the stack entry of the calling function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1532 Therefore, there is no limit on the number of nested tail calls that
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1533 a program can execute.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1534 However, a tail call erases any debug information about the
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1535 calling function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1536 Note that a tail call only happens with a particular syntax,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1537 where the <b>return</b> has one single function call as argument;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1538 this syntax makes the calling function return exactly
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1539 the returns of the called function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1540 So, none of the following examples are tail calls:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1541
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1542 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1543 return (f(x)) -- results adjusted to 1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1544 return 2 * f(x)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1545 return x, f(x) -- additional results
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1546 f(x); return -- results discarded
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1547 return x or f(x) -- results adjusted to 1
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1548 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1549
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1550
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1551
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1552
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1553 <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	1554
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1555 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1556 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	1557
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1558 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1559 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	1560 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	1561 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1562
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1563 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1564 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	1565
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1566 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1567 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	1568 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	1569 funcname ::= Name {‘<b>.</b>’ Name} [‘<b>:</b>’ Name]
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1570 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1571
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1572 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1573 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1574
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1575 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1576 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1577 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1578
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1579 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1580 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1581
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1582 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1583 f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1584 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1585
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1586 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1587 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1588
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1589 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1590 function t.a.b.c.f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1591 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1592
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1593 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1594 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1595
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1596 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1597 t.a.b.c.f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1598 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1599
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1600 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1601 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1602
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1603 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1604 local function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1605 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1606
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1607 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1608 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1609
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1610 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1611 local f; f = function () <em>body</em> end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1612 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1613
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1614 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1615 not to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1616
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1617 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1618 local f = function () <em>body</em> end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1619 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1620
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1621 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1622 (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	1623 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	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 A function definition is an executable expression,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1628 whose value has type <em>function</em>.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1629 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	1630 all its function bodies are precompiled too.
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1631 Then, whenever Luan executes the function definition,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1632 the function is <em>instantiated</em> (or <em>closed</em>).
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1633 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	1634 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	1635
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1636
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1637 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1638 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	1639 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	1640
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1641 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1642 parlist ::= namelist [‘<b>,</b>’ ‘<b>...</b>’] \| ‘<b>...</b>’
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1643 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1644
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1645 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1646 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	1647 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	1648 the length of the list of parameters,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1649 unless the function is a <em>vararg function</em>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1650 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	1651 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	1652 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	1653 instead, it collects all extra arguments and supplies them
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1654 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	1655 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	1656 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	1657 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	1658 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	1659 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	1660 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	1661 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	1662 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	1663 (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	1664
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1665
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1666 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1667 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	1668
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1669 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1670 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	1671 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	1672 function r() return 1,2,3 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1673 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1674
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1675 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1676 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	1677 to the vararg expression:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1678
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1679 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1680 CALL PARAMETERS
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1681
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1682 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	1683 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	1684 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	1685 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	1686 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	1687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1688 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	1689 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	1690 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	1691 g(5, r()) a=5, b=1, ... --> 2 3
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1692 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1693
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1694 <p>
464 eddf7c73373b fix references in the manual Franklin Schmidt <fschmidt@gmail.com> parents: 429 diff changeset	1695 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	1696 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	1697 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	1698 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	1699
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1700
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1701 <h4 heading><a name="template_expr">Template Expressions</a></h4>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1702
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1703 <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	1704
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1705 <pre><%=Html.encode[[
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1706 local name = "Bob"
469 85467f95ab13 minor Franklin Schmidt <fschmidt@gmail.com> parents: 468 diff changeset	1707 write( %>Hello <%= name %>!<% )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1708 ]]%></pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1709
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1710 <p>This is equivalent to the code:</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1711
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1712 <pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1713 local name = "Bob"
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1714 write( "Hello ", name, "!" )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1715 </pre>
465 47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1716
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1717 <p>The strings in template expressions may be multiple lines.</p>
47c7de1f2322 documentation work Franklin Schmidt <fschmidt@gmail.com> parents: 464 diff changeset	1718
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1719
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1720
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1721 <h3 heading><a name="visibility">Visibility Rules</a></h3>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1722
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1723 <p>
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1724 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	1725 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	1726 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	1727 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	1728 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1729
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1730 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1731 x = 10 -- global variable
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1732 do -- new block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1733 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	1734 print(x) --> 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1735 x = x+1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1736 do -- another block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1737 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	1738 print(x) --> 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1739 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1740 print(x) --> 11
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1741 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1742 print(x) --> 10 (the global one)
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1743 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1744
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1745 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1746 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	1747 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	1748 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	1749
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1751 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1752 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	1753 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	1754 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1755 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	1756 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	1757 inside the inner function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1758
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1760 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1761 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	1762 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1763 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1764
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1765 <pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1766 a = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1767 local x = 20
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1768 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	1769 local y = 0
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1770 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	1771 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1772 </pre>
417 a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1773
a40e99cf0b0b work on manual Franklin Schmidt <fschmidt@gmail.com> parents: 396 diff changeset	1774 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1775 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	1776 (that is, ten instances of the anonymous function).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1777 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	1778 while all of them share the same <code>x</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1779
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1780
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1781
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1782
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1783
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1784 <h2 heading><a name="libs">Standard Libraries</a></h2>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1785
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1786 <p>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1787 The standard Luan libraries provide useful functions
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1788 that are implemented both in Java and in Luan itself.
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1789 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	1790 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	1791 (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	1792 others provide access to "outside" services (e.g., I/O).
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1793
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1794
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1795 <h3 heading><a name="default_lib">Default Environment</a></h3>
468 9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1796
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1797 <p>
9b51e2413cab documentation Franklin Schmidt <fschmidt@gmail.com> parents: 465 diff changeset	1798 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	1799
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1800
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1801 <h4 heading><a name="require"><code>java ()</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1802
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1803 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1804 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	1805
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1806
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1807 <h4 heading><a name="require"><code>require (mod_uri)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1808
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1809 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1810 Example use:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1811
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1812 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1813 local Table = require "luan:Table"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1814 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1815
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1816 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1817 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1818
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1819 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1820 local function require(mod_name)
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1821 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	1822 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1823 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1824
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1825
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1826 <h3 heading><a name="luan_lib">Basic Functions</a></h3>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1827
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1828 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1829 Include this library by:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1830
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1831 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1832 local Luan = require "luan:Luan"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1833 </pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1834
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	1835 <p>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1836 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	1837
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1838
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1839 <h4 heading><a name="Luan.assert"><code>Luan.assert (v [, message])</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1840
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1841 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1842 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1843
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1844 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1845 function Luan.assert(v,message)
472 f4aca5a5346a minor documentation Franklin Schmidt <fschmidt@gmail.com> parents: 470 diff changeset	1846 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	1847 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1848 </pre>
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
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1851 <h4 heading><a name="Luan.assert_binary"><code>Luan.assert_binary (v)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1852
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1853 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1854 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1855
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1856 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1857 function Luan.assert_binary(v)
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1858 local v_type = Luan.type(v)
472 f4aca5a5346a minor documentation Franklin Schmidt <fschmidt@gmail.com> parents: 470 diff changeset	1859 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	1860 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1861 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1862
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1863
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1864 <h4 heading><a name="Luan.assert_boolean"><code>Luan.assert_boolean (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1865
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1866 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1867 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	1868
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1869
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1870 <h4 heading><a name="Luan.assert_integer"><code>Luan.assert_integer (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1871
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1872 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1873 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	1874
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1875
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1876 <h4 heading><a name="Luan.assert_long"><code>Luan.assert_long (v)</code></a></h4>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1879 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	1880
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1881
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1882 <h4 heading><a name="Luan.assert_number"><code>Luan.assert_number (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1883
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1884 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1885 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	1886
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1887
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1888 <h4 heading><a name="Luan.assert_string"><code>Luan.assert_string (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1889
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1890 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1891 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	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 <h4 heading><a name="Luan.assert_table"><code>Luan.assert_table (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1895
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1896 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1897 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	1898
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1899
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1900 <h4 heading><a name="Luan.do_file"><code>Luan.do_file ([uri])</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1901
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1902 <p>
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1903 Could be defined as:
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1904
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1905 <pre>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1906 function Luan.do_file(uri)
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1907 return <a href="#Luan.load_file">Luan.load_file</a>(uri)()
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1908 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1909 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1910
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1911
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 <h4 heading><a name="Luan.error"><code>Luan.error (message)</code></a></h4>
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1914
5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1915 <p>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1916 Throws an error containing the message.
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1917
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1918 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1919 Could be defined as:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1920
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1921 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1922 function Luan.error(message)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1923 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	1924 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1925 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1926
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1927
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1928
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1929 <h4 heading><a name="Luan.get_metatable"><code>Luan.get_metatable (table)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1930
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1931 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1932 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	1933 Otherwise,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1934 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	1935 returns the associated value.
470 5627eb637eb4 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 469 diff changeset	1936 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	1937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1938
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1939 <h4 heading><a name="Luan.ipairs"><code>Luan.ipairs (t)</code></a></h4>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1940
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1941 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1942 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	1943 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1944
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1945 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1946 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	1947 </pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1948
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1949 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1950 will iterate over the key–value pairs
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1951 (<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	1952 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	1953
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1954 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1955 Could be defined as:
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1956
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1957 <pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1958 function Luan.ipairs(t)
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1959 local i = 0
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1960 return function()
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1961 if i < #t then
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1962 i = i + 1
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1963 return i, t[i]
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1964 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1965 end
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1966 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1967 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1968
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
581 5d4652d78ce0 minor Franklin Schmidt <fschmidt@gmail.com> parents: 580 diff changeset	1971 <h4 heading><a name="Luan.load"><code>Luan.load (text, [source_name [env, [, allow_expression]]])</code></a></h4>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1972
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1973 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1974 Loads a chunk.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	1975
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1976 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1977 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	1978 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	1979 returns the compiled chunk as a function;
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1980 otherwise, throws an error.
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1981
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1982 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1983 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	1984
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1985 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1986 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	1987
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1988 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1989 If the <code>allow_expression</code> parameter is <code>true</code> then the entire text can be nothing more than an expression in which case the chunk returns the value of this expression.
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
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1992 <h4 heading><a name="Luan.load_file"><code>Luan.load_file (file_uri [, add_extension])</code></a></h4>
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 Similar to <a href="#Luan.load"><code>load</code></a>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	1996 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	1997 or from the standard input,
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1998 if no file uri is given.
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	1999
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2000 <p>
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2001 Could be defined as:
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2002
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2003 <pre>
474 00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2004 function Luan.load_file(file_uri,add_extension)
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2005 file_uri = file_uri or "stdin:"
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2006 local f = Io.uri(file_uri,add_extension)
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2007 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	2008 return <a href="#Luan.load">Luan.load</a>( f.read_text(), file_uri )
00646edc9d92 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 472 diff changeset	2009 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2010 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2011
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2012
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2013 <h4 heading><a name="Luan.new_error"><code>Luan.new_error (message)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2014
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2015 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2016 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	2017
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2018 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2019 To print the current stack trace, you could do:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2020
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2021 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2022 Io.print( Luan.new_error "stack" )
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2023 </pre>
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 <h4 heading><a name="Luan.pairs"><code>Luan.pairs (t)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2027
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2028 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2029 If <code>t</code> has a metamethod <code>__pairs</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2030 calls it with <code>t</code> as argument and returns the
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2031 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	2032
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2033
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2034 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2035 Otherwise,
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2036 returns a function
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2037 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2038
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2039 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2040 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	2041 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2042
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2043 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2044 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	2045
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2046
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2047
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2048 <h4 heading><a name="Luan.pcall"><code>Luan.pcall (f [, arg1, ···])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2049
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2050 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2051 Calls function <code>f</code> with
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2052 the given arguments in <em>protected mode</em>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2053 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	2054 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	2055 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	2056 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	2057 which is true if the call succeeds without errors.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2058 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	2059 after this first result.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2060 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	2061
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2062
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2063
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2065 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2066 <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	2067 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	2068 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	2069 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	2070 <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	2071 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	2072 for instance for debugging.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2073 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	2074 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	2075
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2076
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2077
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2078 <h4 heading><a name="Luan.range"><code>Luan.range (start, stop [, step])</code></a></h4>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2079
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2080 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2081 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	2082
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2083 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2084 Example use:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2085
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2086 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2087 for i in range(1,10) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2088 Io.print("count up:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2089 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2090 for i in range(10,0,-1) do
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2091 Io.print("count down:",i)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2092 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2093 </pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2094
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2095 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2096 Could be defined as:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2097
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2098 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2099 function Luan.range(start, stop, step)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2100 step = step or 1
478 eb6d90fb0b5c documentation Franklin Schmidt <fschmidt@gmail.com> parents: 476 diff changeset	2101 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	2102 local i = start
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2103 return function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2104 if step > 0 and i <= stop or step < 0 and i >= stop then
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2105 local rtn = i
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2106 i = i + step
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2107 return rtn
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2108 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2109 end
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2110 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2111 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2112
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2113
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 <h4 heading><a name="Luan.raw_equal"><code>Luan.raw_equal (v1, v2)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2116
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2117 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2118 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	2119 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2120 Returns a boolean.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2123
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2124 <h4 heading><a name="Luan.raw_get"><code>Luan.raw_get (table, index)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2125
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2126 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2127 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	2128 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2129 <code>table</code> must be a table;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2130 <code>index</code> may be any 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
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2133
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2134 <h4 heading><a name="Luan.raw_len"><code>Luan.raw_len (v)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2135
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2136 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2137 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	2138 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	2139 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2140 Returns an integer.
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
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2144 <h4 heading><a name="Luan.raw_set"><code>Luan.raw_set (table, index, value)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2145
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2146 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2147 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	2148 without invoking any metamethod.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2149 <code>table</code> must be a table,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2150 <code>index</code> any value different from <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2151 and <code>value</code> any Lua value.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2152
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2153
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2154 <h4 heading><a name="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	2155
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2156 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2157 Sets the metatable for the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2158 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	2159 removes the metatable of the given table.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2160 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	2161 raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2162
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2163
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2164
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2165 <h4 heading><a name="Luan.to_string"><code>Luan.to_string (v)</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2166
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2167 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2168 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	2169 converts it to a string in a human-readable format.
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2170
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2171 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2172 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	2173 then <code>to_string</code> calls the corresponding value
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2174 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	2175 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	2176
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2177
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2178
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2179 <h4 heading><a name="Luan.try"><code>Luan.try (t)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2180
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2181 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2182 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. Returns the result of the "try" block or the "catch" block.
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2183
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2184 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2185 Example use:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2186
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2187 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2188 try {
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2189 function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2190 a_dangerous_fn()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2191 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2192 catch = function(e)
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2193 -- handle error
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2194 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2195 finally = function()
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2196 -- clean up
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2197 end;
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2198 }
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2199 </pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2200
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2201 <p>
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2202 Could be defined as:
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2203
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2204 <pre>
482 7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2205 function Luan.try(t)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2206 local r = { <a href="#Luan.pcall">Luan.pcall</a>(t[1]) }
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2207 if r[1] then
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2208 Table.remove(r,1)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2209 elseif t.catch ~= nil then
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2210 r = { t.catch(r[2]) }
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2211 else
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2212 t.finally and t.finally()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2213 r[2].throw()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2214 end
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2215 t.finally and t.finally()
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2216 return Table.unpack(r)
7e9fcfbf22ec documentation Franklin Schmidt <fschmidt@gmail.com> parents: 479 diff changeset	2217 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2218 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2219
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2220
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2221 <h4 heading><a name="Luan.type"><code>Luan.type (v)</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2222
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2223 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2224 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	2225 The possible results of this function are
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2226 "<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	2227 "<code>number</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2228 "<code>string</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2229 "<code>binary</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2230 "<code>boolean</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2231 "<code>table</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2232 "<code>function</code>",
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2233 and "<code>java</code>".
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2234
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 <h4 heading><a name="Luan.values"><code>Luan.values (···)</code></a></h4>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2237
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2238 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2239 Returns a function so that the construction
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2240
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2241 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2242 for v in Luan.values(···) do <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2243 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2244
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2245 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2246 will iterate over all values of <code>···</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2247
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2248
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2249
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2250 <h4 heading><a name="Luan.VERSION"><code>Luan.VERSION</code></a></h4>
475 7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2251
7ac0891718eb documentation Franklin Schmidt <fschmidt@gmail.com> parents: 474 diff changeset	2252 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2253 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	2254 holds a string containing the current interpreter version.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2255 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	2256
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2257
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2258
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2259
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2260
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2261
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2262 <h3 heading><a name="package_lib">Modules</a></h3>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2263
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2264 <p>
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2265 Include this library by:
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2266
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2267 <pre>
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2268 local Package = require "luan:Package"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2269 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2270
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2271 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2272 The package library provides basic
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2273 facilities for loading modules in Luan.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2274
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2275
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2276 <h4 heading><a name="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	2277
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2278 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2279 Loads the given module.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2280 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	2281 to determine whether <code>mod_uri</code> is already loaded.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2282 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	2283 at <code>Package.loaded[mod_uri]</code>.
476 cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2284 Otherwise, it tries to load a new value for the module.
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2285
cd22e4694ea3 documentation Franklin Schmidt <fschmidt@gmail.com> parents: 475 diff changeset	2286 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2287 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	2288
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2289 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2290 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> (using <code>add_extension</code>=true). 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.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2291
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2292 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2293 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	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 <h4 heading><a name="Package.loaded"><code>Package.loaded</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2299
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2300
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2301 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2302 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	2303 modules are already loaded.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2304 When you load a module <code>mod_uri</code> and
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2305 <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	2306 <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	2307
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2308
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2309 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2310 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	2311 assignments to this variable do not change the
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2312 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	2313
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2314
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2315
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2316
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2317
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2318
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2319 <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	2320
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2321 <p>
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2322 Include this library by:
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2323
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2324 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2325 local String = require "luan:String"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2326 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2327
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2328 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2329 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	2330 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	2331 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	2332 (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	2333 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	2334 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	2335 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	2336
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2338
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2339 <h4 heading><a name="String.char"><code>String.char (···)</code></a></h4>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2340
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2341 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2342 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	2343 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	2344 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	2345 to its corresponding argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2346
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2347
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2348 <h4 heading><a name="String.concat"><code>String.concat (···)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2349
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2350 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2351 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	2352
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2353
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2354
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2355 <h4 heading><a name="String.encode"><code>String.encode (s)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2356
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2357 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2358 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	2359
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2360
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2361
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2362
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2363 <h4 heading><a name="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	2364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2365 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2366 Looks for the first match of
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2367 <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	2368 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	2369 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	2370 otherwise, it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2371 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	2372 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	2373 its default value is 1 and can be negative.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2374 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	2375 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	2376 so the function does a plain "find substring" operation,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2377 with no characters in <code>pattern</code> being considered magic.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2378 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	2379
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2380 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2381 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	2382 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	2383 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	2384 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2385
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2386
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2388
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2389 <h4 heading><a name="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	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 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	2394 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	2395 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	2396
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2397 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2398 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	2399
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2400
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2401
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2402 <h4 heading><a name="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	2403
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2404 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2405 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	2406 each time it is called,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2407 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	2408 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2409 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	2410 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	2411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2412
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2413 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2414 As an example, the following loop
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2415 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	2416 printing one per line:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2417
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2418 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2419 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2420 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2421 print(w)
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2422 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2423 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2424
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2425 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2426 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	2427 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	2428
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2429 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2430 local t = {}
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2431 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2432 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	2433 t[k] = v
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2434 end
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2435 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2436
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2437 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2438 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	2439 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	2440
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2441
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2442
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2443 <h4 heading><a name="String.gsub"><code>String.gsub (s, pattern, repl [, n])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2444
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2445 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2446 Returns a copy of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2447 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	2448 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	2449 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	2450 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	2451 <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	2452 the total number of matches that occurred.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2453 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	2454
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2455
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2456 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2457 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	2458 The character <code>\</code> works as an escape character.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2459 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	2460 with <em>d</em> between 1 and 9,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2461 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	2462 The sequence <code>$0</code> stands for the whole match.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2463
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2464
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2465 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2466 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	2467 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	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>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2471 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	2472 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	2473 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2476 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2477 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2478 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	2479 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	2480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2482 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2483 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	2484 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	2485 then it is used as the replacement string;
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2486 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	2487 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	2488 (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	2489
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2490
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2491 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2492 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2493
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2494 <pre>
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2495 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	2496 --> 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	2497
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2498 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	2499 --> x="hello hello world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2500
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2501 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	2502 --> x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2503
e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2504 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	2505 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2506 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2507 --> x="4+5 = 9"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2509 local t = {name="lua", version="5.3"}
555 e25ba7a2e816 some String documentation and fixes Franklin Schmidt <fschmidt@gmail.com> parents: 553 diff changeset	2510 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	2511 --> x="lua-5.3.tar.gz"
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2512 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2513
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2514
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2515
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2516 <h4 heading><a name="String.literal"><code>String.literal (s)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2517 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2518 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	2519
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2520
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2521 <h4 heading><a name="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	2522 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2523 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	2524 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	2525 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	2526
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2528
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2529
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2530 <h4 heading><a name="String.match"><code>String.match (s, pattern [, init])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2531
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2532 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2533 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2534 <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	2535 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	2536 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	2537 otherwise it returns <b>nil</b>.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2538 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	2539 then the whole match is returned.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2540 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	2541 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	2542 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	2543
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2544
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2545 <h4 heading><a name="String.matches"><code>String.matches (s, pattern)</code></a></h4>
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 boolean indicating whether the entire string <code>s</code> matches <code>pattern</code>.
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 <h4 heading><a name="String.rep"><code>String.rep (s, n [, sep])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2552 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2553 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	2554 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	2555 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	2556 (that is, no separator).
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2557 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	2558
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2559
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2560
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2561
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2562 <h4 heading><a name="String.reverse"><code>String.reverse (s)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2563 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2564 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	2565
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2566
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2567
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2568
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2569 <h4 heading><a name="String.sub"><code>String.sub (s, i [, j])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2570
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2571 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2572 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2573 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	2574 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2575 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	2576 (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	2577 In particular,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2578 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	2579 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2580 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	2581 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	2582
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2583
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2584 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2585 If, after the translation of negative indices,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2586 <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	2587 it is corrected to 1.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2588 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	2589 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	2590 If, after these corrections,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2591 <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	2592 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	2593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2594
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2595
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2596 <h4 heading><a name="String.to_binary"><code>String.to_binary (s)</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2597
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2598 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2599 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	2600
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2601
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2602
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2603 <h4 heading><a name="String.to_number"><code>String.to_number (s [, base])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2604
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2605 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2606 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2607 <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	2608 If the argument is
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2609 a string convertible to a number,
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2610 then <code>to_number</code> returns this number;
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2611 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2612
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2613 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2614
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2615
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2616 <p>
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2617 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2618 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	2619 an integer numeral in that base.
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2620 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	2621 represents 10, '<code>B</code>' represents 11, and so forth,
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2622 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2623 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	2624 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2625
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2626
d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2627
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2628 <h4 heading><a name="String.trim"><code>String.trim (s)</code></a></h4>
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 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2631 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	2632
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2633
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2634
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2635
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2636 <h4 heading><a name="String.unicode"><code>String.unicode (s [, i [, j]])</code></a></h4>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2637
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2638 <p>
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2639 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	2640 <code>s[i+1]</code>, ..., <code>s[j]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2641 The default value for <code>i</code> is 1;
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2642 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	2643 These indices are corrected
562 7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2644 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	2645
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2646
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2647
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2648
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2649
7cc9d4a53d3b remove SimplyHTML from documentation Franklin Schmidt <fschmidt@gmail.com> parents: 556 diff changeset	2650 <h4 heading><a name="String.upper"><code>String.upper (s)</code></a></h4>
556 d02f43598ba3 finish String documentation Franklin Schmidt <fschmidt@gmail.com> parents: 555 diff changeset	2651 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2652 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	2653 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	2654 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	2655 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	2656
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2657
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2658
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2659
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2660
567 6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2661 <h3 heading><a name="binary_lib">Binary Manipulation</a></h3>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2662
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2663 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2664 Include this library by:
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2665
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2666 <pre>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2667 local Binary = require "luan:Binary"
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2668 </pre>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2669
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2670
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2671 <h4 heading><a name="Binary.binary"><code>Binary.binary (···)</code></a></h4>
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 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2674 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2675 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2676 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2677 to its corresponding argument.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2678
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2679
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2680 <h4 heading><a name="Binary.byte"><code>Binary.byte (b [, i [, j]])</code></a></h4>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2681
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2682 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2683 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2684 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2685 The default value for <code>i</code> is 1;
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2686 the default value for <code>j</code> is <code>i</code>.
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2687 These indices are corrected
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2688 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	2689
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2690
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2691 <h4 heading><a name="Binary.to_string"><code>Binary.to_string (b)</code></a></h4>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2692 <p>
6c00b8a59240 document Binary Franklin Schmidt <fschmidt@gmail.com> parents: 566 diff changeset	2693 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	2694
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2695
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2696
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2697
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2698 <h3 heading><a name="table_lib">Table Manipulation</a></h3>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2699
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2700 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2701 Include this library by:
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2702
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2703 <pre>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2704 local Table = require "luan:Table"
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2705 </pre>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2706
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2707 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2708 This library provides generic functions for table manipulation.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2709 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2710
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2711
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2712
580 1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2713 <h4 heading><a name="Table.clear"><code>Table.clear (tbl)</code></a></h4>
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2714
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2715 <p>
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2716 Clears the table.
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2717
1e69d9c21461 add Table.clear(); Franklin Schmidt <fschmidt@gmail.com> parents: 567 diff changeset	2718
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2719 <h4 heading><a name="Table.concat"><code>Table.concat (list [, sep [, i [, j]]])</code></a></h4>
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 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2722 Given a list,
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2723 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	2724 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	2725 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	2726 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	2727 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	2728
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2729
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2730 <h4 heading><a name="Table.copy"><code>Table.copy (tbl [, i [, j]])</code></a></h4>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2731
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2732 <p>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2733 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	2734 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	2735 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2736
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2737
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2738
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2739 <h4 heading><a name="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	2740
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2741 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2742 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	2743 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2744 <code>list[pos], list[pos+1], ···, list[#list]</code>.
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2745
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2746
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2747
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2748 <h4 heading><a name="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	2749
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2750 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2751 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	2752 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	2753 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	2754
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2755
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2756
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2757
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2758 <h4 heading><a name="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	2759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2760
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2761 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2762 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	2763 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	2764 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	2765 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	2766 <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	2767 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	2768 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	2769 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	2770 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	2771
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2772
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2773
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2774
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2775 <h4 heading><a name="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	2776
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2777 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2778 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	2779 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	2780 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	2781 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	2782 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	2783 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	2784 (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	2785 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	2786 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	2787
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2788 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2789 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	2790 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	2791 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	2792
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2793
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2794
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2795 <h4 heading><a name="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	2796
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2797 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2798 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	2799 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	2800
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2801 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2802 return list[i], list[i+1], ···, list[j]
565 22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2803 </pre>
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2804
22bfd8a2eaee do Table documentation; Franklin Schmidt <fschmidt@gmail.com> parents: 562 diff changeset	2805 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2806 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	2807
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2809
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2810
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2811 <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	2812
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2813 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2814 Include this library by:
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2815
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2816 <pre>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2817 local Number = require "luan:Number"
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2818 </pre>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2819
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2820
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2821 <h4 heading><a name="Number.double"><code>Number.double (x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2822 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2823 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2824
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2825
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2826 <h4 heading><a name="Number.integer"><code>Number.integer (x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2827 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2828 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	2829 returns that integer.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2830 Otherwise throws an error.
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 <h4 heading><a name="Number.long"><code>Number.long (x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2834 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2835 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	2836 returns that long.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2837 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2838
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2839
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2840 <h4 heading><a name="Number.long_to_string"><code>Number.long_to_string (i, radix)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2841 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2842 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	2843
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2844
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2845 <h4 heading><a name="Number.type"><code>Number.type (x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2846 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2847 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	2848
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2849
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
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2852 <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	2853
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2854 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2855 Include this library by:
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2856
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2857 <pre>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2858 local Math = require "luan:Math"
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2859 </pre>
371 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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2862 This library provides basic mathematical functions.
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2863 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	2864
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2865
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2866 <h4 heading><a name="Math.abs"><code>Math.abs (x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2867
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2868 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2869 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	2870
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2871
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2872
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2873 <h4 heading><a name="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	2874
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2875 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2876 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	2877
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2878
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2879
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2880
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2881 <h4 heading><a name="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	2882
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2883 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2884 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	2885
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2886
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2887
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2888
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2889 <h4 heading><a name="Math.atan"><code>Math.atan (y, x)</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2890
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2891 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2892 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	2893 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	2894 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2895 (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	2896
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2897
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2898
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2899
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2900 <h4 heading><a name="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	2901
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2902 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2903 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2907
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2908 <h4 heading><a name="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	2909
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2910 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2911 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	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
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2916 <h4 heading><a name="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	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 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	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
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2924 <h4 heading><a name="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	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 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	2928 (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	2929
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2930
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2931
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2932
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2933 <h4 heading><a name="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	2934
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2935 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2936 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	2937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2940
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2941 <h4 heading><a name="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	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 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	2945 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2946
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2947
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2948
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2949
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2950 <h4 heading><a name="Math.huge"><code>Math.huge</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2951
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2952 <p>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2953 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	2954
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2955
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 <h4 heading><a name="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	2959
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2960 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2961 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	2962 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	2963 (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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2967
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2968 <h4 heading><a name="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	2969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2970 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2971 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	2972 according to the Lua operator <code><</code>.
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
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2976
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2977 <h4 heading><a name="Math.max_integer"><code>Math.max_integer</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2978 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2979 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2983
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2984 <h4 heading><a name="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	2985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2986 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2987 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	2988 according to the Lua operator <code><</code>.
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
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2991
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2992
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2993 <h4 heading><a name="Math.min_integer"><code>Math.min_integer</code></a></h4>
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	2994 <p>
371 e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2995 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	2996
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2997
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2998
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	2999
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3000 <h4 heading><a name="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	3001
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3002 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3003 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	3004
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3005
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3006
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3007
90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3008 <h4 heading><a name="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	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 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	3012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3013
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3014
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3015
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3016 <h4 heading><a name="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	3017
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3018 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3019 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	3020
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3021
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3023
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3024 <h4 heading><a name="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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3028 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3029 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	3030 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	3031 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	3032 <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	3033 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	3034 (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	3035 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	3036
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3037
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3038 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3039 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	3040 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	3041 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	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
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3046 <h4 heading><a name="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	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 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	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
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3054 <h4 heading><a name="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	3055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3056 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3057 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	3058 (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	3059
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3060
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3061
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3062
566 90b93790c544 Number and Math documentation and minor changes Franklin Schmidt <fschmidt@gmail.com> parents: 565 diff changeset	3063 <h4 heading><a name="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	3064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3065 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3066 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3070
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3073
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3074
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3075 <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	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 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	3079 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	3080 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	3081 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3082 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	3083 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	3084
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3085
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3086 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3087 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	3088 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	3089 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	3090 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	3091 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	3092
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3093
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3094 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3095 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	3096 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	3097 <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	3098 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	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 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3103 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	3104 (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	3105 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	3106 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	3107 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3108 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	3109 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3110 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	3111 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	3112
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3113
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3114 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3115 <hr><h3><a name="pdf-io.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	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 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	3120 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	3121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3123
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3124
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3125 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3126 <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	3127
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3128
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3129 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3130 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	3131
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3132
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3133
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3136 <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	3137
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3138
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3139 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3140 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	3141 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	3142 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	3143 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	3144 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3145 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	3146
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3147
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3148 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3149 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	3150 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	3151
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3152
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3153
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3154
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3155 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3156 <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	3157
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3158
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3159 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3160 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	3161 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	3162 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	3163 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	3164 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	3165
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3166
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3167 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3168 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	3169 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	3170 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	3171 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	3172
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3175 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	3176 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	3177
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3178
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3179
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3180
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3181 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3182 <hr><h3><a name="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	3183
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3184
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3185 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3186 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	3187 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	3188 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	3189 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3193 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	3194
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3195 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3196 <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	3197 <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	3198 <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	3199 <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	3200 <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	3201 <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	3202 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	3203 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3204 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	3205 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	3206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3207
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3208
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3209
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3210 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3211 <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	3212
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3213
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3214 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3215 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	3216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3217
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3218
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3221 <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	3222
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3223
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3224 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3225 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	3226 on all platforms.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3227
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3229 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3230 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	3231 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	3232 (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	3233 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	3234 (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	3235
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3236
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3237
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3238
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3239 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3240 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3244 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	3245
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3249 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3250 <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	3251
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3253 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3254 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	3255 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	3256 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	3257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3258
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3259
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 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3266 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	3267 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	3268 <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	3269 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	3270
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3271
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3272
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3273
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3274 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3275 <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	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 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	3280
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3281
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3285 <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	3286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3288 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3289 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3290 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	3291 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	3292 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3296 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	3297 <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	3298 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	3299
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3300
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3301
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3302
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3303 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3304 <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	3305
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3306
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3307 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3308 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	3309
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3310
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3311
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3312
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3313 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3314 <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	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 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	3319 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	3320 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	3321 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	3322 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	3323 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	3324
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3325 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3326 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	3327 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3328 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	3329 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	3330 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	3331 when the loop ends.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3332
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3333
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3334 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3335 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	3336 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	3337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3338
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3339
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3340
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3341 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3342 <hr><h3><a name="pdf-file: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	3343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3344
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3345 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3346 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	3347 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	3348 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3349 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	3350 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	3351 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3352 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	3353 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3354 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	3355 (see below).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3356
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3357
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3358 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3359 The available formats are
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3362
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3363 <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	3364 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	3365 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	3366 (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	3367 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	3368 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	3369 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	3370 (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	3371 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	3372 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3373
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3374 <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	3375 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	3376 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3377
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3378 <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	3379 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	3380 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	3381 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3382
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3383 <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	3384 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	3385 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	3386 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	3387 </li>
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 <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	3390 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	3391 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	3392 </li>
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 <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	3395 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	3396 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	3397 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	3398 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	3399 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	3400 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3401
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3402 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3403 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	3404
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3405
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3406
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3407
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3408 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3409 <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	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 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	3414 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	3415 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	3416 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	3417
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3418 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3419 <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	3420 <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	3421 <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	3422 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3423 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	3424 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	3425 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	3426 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	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 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	3431 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	3432 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	3433 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	3434 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	3435 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	3436 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	3437 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	3438
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3439
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3440
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3441
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3442 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3443 <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	3444
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3445
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3446 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3447 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	3448 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	3449
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3450 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3451
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3452 <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	3453 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	3454 </li>
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 <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	3457 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	3458 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	3459 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	3460 </li>
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 <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	3463 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	3464 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	3465 (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	3466 </li>
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 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3469 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	3470 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	3471 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3477 <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	3478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3479
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3480 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3481 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	3482 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	3483
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3484
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3485 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3486 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	3487 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	3488
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3489
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3490
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 <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	3496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3497 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3498 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	3499
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3500
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3501 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3502 <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	3503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3504
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3505 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3506 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	3507 used by the program.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3511
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3512 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3513 <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	3514
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3515
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3516 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3517 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	3518 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	3519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3520
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3521 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3522 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	3523 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	3524 (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	3525 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	3526
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3528 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3529 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	3530 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	3531 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3532 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	3533 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	3534 <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	3535 <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	3536 <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	3537 <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	3538 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	3539 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	3540 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	3541
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3542
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3543 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3544 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	3545 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	3546 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	3547
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3548
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3549 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3550 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3551 <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	3552 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	3553 (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	3554
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3555
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3556 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3557 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3558 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	3559 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	3560
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3561
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3562
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3563
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3564 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3565 <hr><h3><a name="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	3566
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3567
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3568 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3569 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	3570 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	3571 (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	3572 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	3573 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	3574
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3575
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3578 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3579 <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	3580
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3583 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	3584 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	3585 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	3586 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	3587 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	3588 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3589 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	3590 as follows:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3591
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3592 <ul>
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 <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	3595 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3596 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	3597 </li>
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 <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	3600 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	3601 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	3602 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3603
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3604 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3605
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3606 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3607 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	3608 <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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3612
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3613 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3614 <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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3618 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	3619 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	3620 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	3621 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	3622 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	3623 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	3624 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	3625 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3629 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	3630 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3634
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3635 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3636 <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	3637
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3638
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3639 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3640 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	3641 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	3642
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3643
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 <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	3648
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3649
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3650 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3651 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	3652 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3653 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	3654 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	3655
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3659 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3660 <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	3661
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3662
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3663 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3664 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	3665 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	3666 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3670
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3671 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3672 <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	3673
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3674
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3675 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3676 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	3677 <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	3678 <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	3679 <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	3680 <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	3681 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	3682 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	3683 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	3684
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3685
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3686 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3687 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	3688 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	3689 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	3690 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	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 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	3695 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	3696 for the given category.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3697
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3698
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3699 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3700 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	3701 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	3702
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3706 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3707 <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	3708
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3709
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3710 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3711 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	3712 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	3713 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	3714 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3715 <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	3716 <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	3717 <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	3718 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	3719 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	3720
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3721
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3722 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3723 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	3724 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	3725 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	3726 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	3727 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	3728 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	3729 <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	3730
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3731
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3732
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3733
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3734 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3735 <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	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 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	3740 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	3741 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	3742 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3746 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3747 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	3748 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3749 (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	3750 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	3751 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	3752 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	3753
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3754
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3755 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3756 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3757 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	3758 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	3759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3760
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3761
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3762
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3763
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3766 <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	3767
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3768 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3769 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3770 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	3771 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	3772 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3773 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	3774 (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	3775 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	3776 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	3777 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	3778 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	3779 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	3780
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3781
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3782 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3783 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	3784 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	3785 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	3786 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	3787 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3788 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	3789
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3790
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3791 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3792 <hr><h3><a name="pdf-debug.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	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 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	3797 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	3798 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	3799 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	3800 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	3801 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	3802 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	3803
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3806 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	3807 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	3808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3809
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3810
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3811
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 <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	3814
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3815
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3816 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3817 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	3818 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	3819 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	3820 (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	3821
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3822
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3823
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3824
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3825 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3826 <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	3827
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3828
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3829 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3830 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	3831 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	3832 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	3833 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	3834 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3835 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	3836 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	3837 (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	3838 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3839 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	3840 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	3841
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3842
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3843 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3844 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	3845 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	3846 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	3847 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	3848 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3849 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	3850 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	3851 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3852 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	3853 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	3854 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3855
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3856
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3857 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3858 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	3859 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	3860 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	3861 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	3862 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	3863 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	3864
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3865
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3866
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3867
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3868 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3869 <hr><h3><a name="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	3870
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3871
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3872 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3873 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	3874 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	3875 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	3876 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	3877
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3878
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3879 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3880 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	3881 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	3882 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	3883 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	3884 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	3885 -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	3886 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	3887 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	3888 (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	3889
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3892 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	3893 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	3894 (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	3895 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	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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3899 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	3900 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3904
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3905 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3906 <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	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 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	3911 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	3912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3913
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3914
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3915
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3916 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3917 <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	3918
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3919
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3920 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3921 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	3922
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3923
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3924
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3925
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3926 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3927 <hr><h3><a name="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	3928
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3931 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	3932 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	3933 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	3934
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3937 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	3938 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	3939 (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	3940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3942
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3943
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3944 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3945 <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	3946
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3948 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3949 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	3950 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	3951 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3953
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3954
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3955
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3956 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3957 <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	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 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	3962 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	3963 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	3964 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	3965 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3966
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3967 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3968 <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	3969 <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	3970 <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	3971 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3972 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3973 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	3974 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	3975
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3976
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3977 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3978 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3979 <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	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 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	3984 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	3985 <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	3986 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3987 <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	3988 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3989 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	3990 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3991 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	3992 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3993 (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	3994 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	3995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3996
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3997
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3998
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	3999 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4000 <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	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 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	4005 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	4006 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	4007 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	4008 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	4009 (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	4010 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	4011
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4013 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4014 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	4015 variable indices and names.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4016
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4017
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4018
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4019
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4020 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4021 <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	4022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4023
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4024 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4025 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	4026 (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	4027 Returns <code>value</code>.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4030
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4031
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4032 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4033 <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	4034
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4035
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4036 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4037 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	4038 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	4039 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	4040 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4041 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	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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4046 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4047 <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	4048
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4049
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4050 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4051 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	4052 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	4053 <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	4054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4056 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4057 Returns <code>udata</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4058
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4063 <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	4064
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4067 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	4068 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	4069 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4070 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	4071 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	4072 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	4073 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	4074 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4075 (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	4076
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4077
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4078
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4081 <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	4082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4083
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4084 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4085 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	4086 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	4087 from the given function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4088
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4089
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4090 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4091 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	4092 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4093 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	4094 (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	4095 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	4096
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4097
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4100 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4101 <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	4102
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4103
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4104 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4105 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	4106 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	4107
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4108
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4109
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4110
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4111
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4112
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4113
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4114 <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	4115
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4116 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4117 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	4118 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	4119 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	4120 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	4121 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	4122 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	4123 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4124 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	4125 Its usage is:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4126
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4127 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4128 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4129 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4130 The options are:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4131
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4132 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4133 <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	4134 <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	4135 <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	4136 <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	4137 <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	4138 <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	4139 <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	4140 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4141 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	4142 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4143 <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	4144 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	4145 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	4146
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4147
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4148 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4149 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	4150 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	4151 (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	4152 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4153 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	4154 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	4155 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	4156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4157
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4158 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4159 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	4160 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	4161 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4162 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	4163 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4164 <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	4165 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	4166
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4167
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4168 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4169 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	4170 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	4171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4172 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4173 $ 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	4174 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4175 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	4176 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	4177 (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	4178
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4181 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4182 <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	4183 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	4184 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	4185 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	4186 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4187 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	4188 (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	4189 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4190 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	4191
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4192 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4193 $ 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	4194 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4195 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	4196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4197 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4198 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	4199 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4200 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4201 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4202 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	4203 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	4204 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	4205 For instance, the call
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4207 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4208 $ 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	4209 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4210 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	4211 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	4212 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	4213 <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	4214 (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	4215 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	4216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4217
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4218 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4219 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4220 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	4221 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4222 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	4223 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	4224 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	4225 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	4226 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	4227 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	4228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4229
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4230 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4231 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	4232 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	4233 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	4234 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	4235 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	4236 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	4237 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	4238
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4241 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4242 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	4243 (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	4244 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	4245 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	4246
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4249 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	4250 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	4251 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4252 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	4253 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	4254 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	4255 as in
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4258 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4259 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4260 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4261 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	4262 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	4263 then
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4266 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4267 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4268 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	4269
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4270
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4271
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4272 <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	4273
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4274 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4275 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	4276 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	4277 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	4278 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	4279 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4280 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	4281
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4284 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	4285 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	4286 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	4287 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	4288 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4289 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	4290 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4291 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	4292 using a new version.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4293
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4294
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4295 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4296 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	4297 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4298 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	4299
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4302 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	4303 change between versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4304
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4305
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4306
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4307 <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	4308 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4309
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4310 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4311 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	4312 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	4313 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	4314 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4315 (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	4316 can give different results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4317
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4318
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4319 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4320 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	4321 (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	4322 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	4323 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	4324 (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	4325 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4326 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	4327 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4328 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	4329 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	4330 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4331
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4332 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4333 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	4334 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	4335 (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	4336 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	4337 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	4338 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	4339
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4340
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4341 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4342 (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	4343 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	4344 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	4345 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4346
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4347 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4348 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	4349 (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	4350 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4351
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4352 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4354
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4357 <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	4358 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4359
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4360 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4361 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	4362 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	4363 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	4364 (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	4365 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	4366 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4367
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4368 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4369 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	4370 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	4371 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4372
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4373 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4374 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	4375 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	4376 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4377
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4378 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4379 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	4380 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	4381 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4382
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4383 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4384 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	4385 <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	4386 <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	4387 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	4388 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	4389 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	4390 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	4391 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4392 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	4393 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4394 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4395
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4396 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4397 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	4398 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	4399 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	4400 (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	4401 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	4402 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	4403 (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	4404 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	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 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4408
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4409
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4410
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4412 <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	4413
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4415 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4417 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4418 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	4419 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	4420 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	4421 Adapt your code accordingly.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4422 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4423
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4424 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4425 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	4426 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	4427 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4428
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4429 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4430 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	4431 (<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	4432 <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	4433 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4434 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	4435 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4436
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4437 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4438 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	4439 (<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	4440 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4441 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	4442 (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	4443 </li>
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 </ul>
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
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 <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	4451
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4452 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4453 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	4454 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	4455 {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	4456 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	4457 (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	4458 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	4459 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4460 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	4461
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4462
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4463
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4464
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4465 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4466
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4467 chunk ::= block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4468
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4469 block ::= {stat} [retstat]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4470
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4471 stat ::= ‘<b>;</b>’ \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4472 varlist ‘<b>=</b>’ explist \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4473 functioncall \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4474 label \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4475 <b>break</b> \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4476 <b>goto</b> Name \|
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4477 <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	4478 <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	4479 <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	4480 <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	4481 <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	4482 <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	4483 <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	4484 <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	4485 <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	4486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4487 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	4488
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4489 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	4490
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4491 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	4492
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4493 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	4494
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4495 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	4496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4497 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	4498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4499 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	4500
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4501 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	4502 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	4503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4504 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	4505
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4506 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	4507
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4508 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	4509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4510 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	4511
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4512 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	4513
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4514 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	4515
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4516 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	4517
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4518 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	4519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4520 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	4521
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4522 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	4523
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4524 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	4525 ‘<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	4526 ‘<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	4527 <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	4528
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4529 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	4530
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4531 </pre>
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4534
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4535
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4536
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4537
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4538
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4539
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4540
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4541
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4542 <HR>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4543 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4544 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4545 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	4546 </SMALL>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4547 <!--
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4548 Last change: minor edit
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4549 -->
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual Franklin Schmidt <fschmidt@gmail.com> parents: diff changeset	4550
372 f08cefa4594c start editing manual Franklin Schmidt <fschmidt@gmail.com> parents: 371 diff changeset	4551 </div>
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	4552
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	4553 </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	4554 </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	4555 <%
386 db23f654f87d make all of website use luan Franklin Schmidt <fschmidt@gmail.com> parents: 382 diff changeset	4556 end

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