annotate website/src/manual.html.luan @ 1239:2612e4307987

minor luanhost logging
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date Wed, 13 Jun 2018 00:53:02 -0600
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1 local Luan = require "luan:Luan.luan"
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2 local Io = require "luan:Io.luan"
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3 local Html = require "luan:Html.luan"
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4 local Http = require "luan:http/Http.luan"
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5 local Shared = require "site:/Shared.luan"
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8 return function()
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9 Io.stdout = Http.response.text_writer()
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10 %>
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11 <!doctype html>
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12 <html>
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13 <head>
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14 <title>Luan Reference Manual</title>
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15 <style>
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16 @import "/site.css";
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17 </style>
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18 </head>
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19 <body>
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20
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21 <div container>
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22 <% Shared.header() %>
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23
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24 <h1>Luan Reference Manual</h1>
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25
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26 <p small>
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27 Original copyright &copy; 2015 Lua.org, PUC-Rio.
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28 Freely available under the terms of the
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29 <a href="http://www.lua.org/license.html">Lua license</a>.
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30 Modified for Luan.
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31 </p>
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32
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33 <hr/>
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34
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35 <h2>Contents</h2>
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36
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37 <div contents><a href="#intro">Introduction</a></div>
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38
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39 <div contents>
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40 <a href="#basic">Basic Concepts</a>
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41 <ul>
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42 <li><a href="#types">Values and Types</a></li>
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43 <li><a href="#env">Environments</a></li>
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44 <li><a href="#error">Error Handling</a></li>
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45 <li><a href="#meta">Metatables and Metamethods</a></li>
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46 <li><a href="#gc">Garbage Collection</a></li>
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47 </ul>
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48 </div>
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49
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50 <div contents>
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51 <a href="#lang">The Language</a>
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52 <ul>
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53 <li><a href="#lex">Lexical Conventions</a></li>
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54 <li><a href="#vars">Variables</a></li>
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55 <li>
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56 <a href="#stmts">Statements</a>
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57 <ul>
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58 <li><a href="#blocks">Blocks</a></li>
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59 <li><a href="#chunks">Chunks</a></li>
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60 <li><a href="#assignment">Assignment</a></li>
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61 <li><a href="#control">Control Structures</a></li>
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62 <li><a href="#for">For Statement</a></li>
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63 <li><a href="#fn_stmt">Function Calls as Statements</a></li>
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64 <li><a href="#local_stmt">Local Declarations</a></li>
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65 <li><a href="#template_stmt">Template Statements</a></li>
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66 </ul>
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67 </li>
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68 <li>
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69 <a href="#expressions">Expressions</a>
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70 <ul>
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71 <li><a href="#arithmetic">Arithmetic Operators</a></li>
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72 <li><a href="#conversions">Coercions and Conversions</a></li>
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73 <li><a href="#relational">Relational Operators</a></li>
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74 <li><a href="#logical_ops">Logical Operators</a></li>
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75 <li><a href="#concatenation">Concatenation</a></li>
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76 <li><a href="#length">The Length Operator</a></li>
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77 <li><a href="#precedence">Precedence</a></li>
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78 <li><a href="#constructors">Table Constructors</a></li>
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79 <li><a href="#fn_calls">Function Calls</a></li>
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80 <li><a href="#fn_def">Function Definitions</a></li>
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81 <li><a href="#template_expr">Template Expressions</a></li>
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82 </ul>
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83 </li>
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84 <li><a href="#visibility">Visibility Rules</a></li>
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85 </ul>
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86 </div>
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87
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88 <div contents>
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89 <a href="#libs">Standard Libraries</a>
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90 <ul>
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91 <li><a href="#default_lib">Default Environment</a></li>
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92 <li><a href="#luan_lib">Basic Functions</a></li>
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93 <li><a href="#package_lib">Modules</a></li>
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94 <li><a href="#string_lib">String Manipulation</a></li>
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95 <li><a href="#binary_lib">Binary Manipulation</a></li>
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96 <li><a href="#table_lib">Table Manipulation</a></li>
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97 <li><a href="#number_lib">Number Manipulation</a></li>
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98 <li><a href="#math_lib">Mathematical Functions</a></li>
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99 </ul>
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100 </div>
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101
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102 <hr/>
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103
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104
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105 <h2 heading><a name="intro">Introduction</a></h2>
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106
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107 <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>
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108
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109 <p>Luan is implemented in Java and is tightly coupled with Java. So it makes a great scripting language for Java programmers.</p>
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110
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111 <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>
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113
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114 <h2 heading><a name="basic">Basic Concepts</a></h2>
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115
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116 <p>This section describes the basic concepts of the language.</p>
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117
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118 <h3 heading><a name="types">Values and Types</a></h3>
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119
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120 <p>
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121 Luan is a <em>dynamically typed language</em>.
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122 This means that
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123 variables do not have types; only values do.
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124 There are no type definitions in the language.
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125 All values carry their own type.
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128 <p>
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129 All values in Luan are <em>first-class values</em>.
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130 This means that all values can be stored in variables,
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131 passed as arguments to other functions, and returned as results.
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134 <p>
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135 There are eight basic types in Luan:
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136 <em>nil</em>, <em>boolean</em>, <em>number</em>,
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137 <em>string</em>, <em>binary</em>, <em>function</em>, <em>java</em>,
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138 and <em>table</em>.
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139 <em>Nil</em> is the type of the value <b>nil</b>,
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140 whose main property is to be different from any other value;
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141 it usually represents the absence of a useful value.
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142 <em>Nil</em> is implemented as the Java value <em>null</em>.
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143 <em>Boolean</em> is the type of the values <b>false</b> and <b>true</b>.
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144 <em>Boolean</em> is implemented as the Java class <em>Boolean</em>.
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145 <em>Number</em> represents both
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146 integer numbers and real (floating-point) numbers.
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147 <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
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148 the underlying Java implementation.
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149
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150 <em>String</em> is implemented as the Java class <em>String</em>.
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151 <em>Binary</em> is implemented as the Java type <em>byte[]</em>.
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152
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153
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154 <p>
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155 Luan can call (and manipulate) functions written in Luan and
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156 functions written in Java (see <a href="#fn_calls">Function Calls</a>).
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157 Both are represented by the type <em>function</em>.
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158
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159
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160 <p>
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161 The type <em>java</em> is provided to allow arbitrary Java objects to
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162 be stored in Luan variables.
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163 A <em>java</em> value is a Java object that isn't one of the standard Luan types.
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164 Java values have no predefined operations in Luan,
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165 except assignment and identity test.
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166 Java values are useful when Java access is enabled in Luan
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167
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168
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169
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170 <p>
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171 The type <em>table</em> implements associative arrays,
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172 that is, arrays that can be indexed not only with numbers,
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173 but with any Luan value except <b>nil</b>.
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174 Tables can be <em>heterogeneous</em>;
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175 that is, they can contain values of all types (except <b>nil</b>).
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176 Any key with value <b>nil</b> is not considered part of the table.
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177 Conversely, any key that is not part of a table has
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178 an associated value <b>nil</b>.
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179
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180
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181 <p>
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182 Tables are the sole data-structuring mechanism in Luan;
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183 they can be used to represent ordinary arrays, sequences,
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184 symbol tables, sets, records, graphs, trees, etc.
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185 To represent records, Luan uses the field name as an index.
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186 The language supports this representation by
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187 providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
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188 There are several convenient ways to create tables in Luan
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189 (see <a href="#constructors">Table Constructors</a>).
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190
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191
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192 <p>
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193 We use the term <em>sequence</em> to denote a table where
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194 the set of all positive numeric keys is equal to {1..<em>n</em>}
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195 for some non-negative integer <em>n</em>,
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196 which is called the length of the sequence (see <a href="#length">The Length Operator</a>).
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197
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198
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199 <p>
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200 Like indices,
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201 the values of table fields can be of any type.
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202 In particular,
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203 because functions are first-class values,
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204 table fields can contain functions.
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205 Thus tables can also carry <em>methods</em> (see <a href="#fn_def">Function Definitions</a>).
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206
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207
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208 <p>
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209 The indexing of tables follows
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210 the definition of raw equality in the language.
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211 The expressions <code>a[i]</code> and <code>a[j]</code>
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212 denote the same table element
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213 if and only if <code>i</code> and <code>j</code> are raw equal
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214 (that is, equal without metamethods).
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215 In particular, floats with integral values
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216 are equal to their respective integers
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217 (e.g., <code>1.0 == 1</code>).
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218
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219
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220 <p>
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221 Luan values are <em>objects</em>:
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222 variables do not actually <em>contain</em> values,
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223 only <em>references</em> to them.
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224 Assignment, parameter passing, and function returns
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225 always manipulate references to values;
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226 these operations do not imply any kind of copy.
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227
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228
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229 <p>
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230 The library function <a href="#Luan.type"><code>Luan.type</code></a> returns a string describing the type
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231 of a given value.
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232
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233
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234
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235
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236
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237 <h3 heading><a name="env">Environments</a></h3>
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238
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239 <p>
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240 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>.
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241
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242 <p>
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243 As will be discussed in <a href="#vars">Variables</a> and <a href=#assignment">Assignment</a>,
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244 any reference to a free name
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245 (that is, a name not bound to any declaration) <code>var</code>
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246 can be syntactically translated to <code>_ENV.var</code> if <code>_ENV</code> is defined.
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247
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248
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249 <h3 heading><a name="error">Error Handling</a></h3>
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250
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251 <p>
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252 Luan code can explicitly generate an error by calling the
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253 <a href="#Luan.error"><code>error</code></a> function.
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254 If you need to catch errors in Luan,
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255 you can use <a href="#Luan.pcall"><code>pcall</code></a> or <a href="#Luan.try"><code>try</code></a>
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256 to call a given function in <em>protected mode</em>.
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257
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258
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259 <p>
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260 Whenever there is an error,
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261 an <em>error table</em>
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262 is propagated with information about the error.
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263 See <a href="#Luan.new_error"><code>Luan.new_error</code></a>.
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264
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265
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266
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267 <h3 heading><a name="meta">Metatables and Metamethods</a></h3>
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268
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269 <p>
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270 Every table in Luan can have a <em>metatable</em>.
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271 This <em>metatable</em> is an ordinary Luan table
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272 that defines the behavior of the original value
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273 under certain special operations.
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274 You can change several aspects of the behavior
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275 of operations over a value by setting specific fields in its metatable.
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276 For instance, when a table is the operand of an addition,
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277 Luan checks for a function in the field "<code>__add</code>" of the table's metatable.
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278 If it finds one,
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279 Luan calls this function to perform the addition.
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280
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281
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282 <p>
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283 The keys in a metatable are derived from the <em>event</em> names;
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284 the corresponding values are called <ii>metamethods</em>.
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285 In the previous example, the event is <code>"add"</code>
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286 and the metamethod is the function that performs the addition.
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287
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288
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289 <p>
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290 You can query the metatable of any table
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291 using the <a href="#Luan.get_metatable"><code>get_metatable</code></a> function.
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292
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293
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294 <p>
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295 You can replace the metatable of tables
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296 using the <a href="#Luan.set_metatable"><code>set_metatable</code></a> function.
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297
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298
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299 <p>
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300 A metatable controls how a table behaves in
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301 arithmetic operations, bitwise operations,
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302 order comparisons, concatenation, length operation, calls, and indexing.
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303
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304
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305 <p>
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306 A detailed list of events controlled by metatables is given next.
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307 Each operation is identified by its corresponding event name.
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308 The key for each event is a string with its name prefixed by
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309 two underscores, '<code>__</code>';
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310 for instance, the key for operation "add" is the
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311 string "<code>__add</code>".
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312 Note that queries for metamethods are always raw;
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313 the access to a metamethod does not invoke other metamethods.
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314 You can emulate how Luan queries a metamethod for an object <code>obj</code>
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315 with the following code:
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316
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317 <pre>
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318 raw_get(get_metatable(obj) or {}, "__" .. event_name)
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319 </pre>
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320
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321 <p>
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322 Here are the events:
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323
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324 <ul>
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325
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326 <li><p><b>"add": </b>
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327 the <code>+</code> operation.
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328
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329 If any operand for an addition is a table,
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330 Luan will try to call a metamethod.
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331 First, Luan will check the first operand (even if it is valid).
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332 If that operand does not define a metamethod for the "<code>__add</code>" event,
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333 then Luan will check the second operand.
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334 If Luan can find a metamethod,
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335 it calls the metamethod with the two operands as arguments,
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336 and the result of the call
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337 (adjusted to one value)
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338 is the result of the operation.
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339 Otherwise,
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340 it raises an error.
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341 </li>
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342
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343 <li><p><b>"sub": </b>
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344 the <code>-</code> operation.
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345
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346 Behavior similar to the "add" operation.
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347 </li>
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348
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349 <li><p><b>"mul": </b>
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350 the <code>*</code> operation.
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351
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352 Behavior similar to the "add" operation.
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353 </li>
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354
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355 <li><p><b>"div": </b>
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356 the <code>/</code> operation.
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357
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358 Behavior similar to the "add" operation.
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359 </li>
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360
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361 <li><p><b>"mod": </b>
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362 the <code>%</code> operation.
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363
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364 Behavior similar to the "add" operation.
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365 </li>
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366
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367 <li><p><b>"pow": </b>
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368 the <code>^</code> (exponentiation) operation.
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369
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370 Behavior similar to the "add" operation.
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371 </li>
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372
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373 <li><p><b>"unm": </b>
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374 the <code>-</code> (unary minus) operation.
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375
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376 Behavior similar to the "add" operation.
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377 </li>
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378
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379 <li><p><b>"concat": </b>
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380 the <code>..</code> (concatenation) operation.
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381
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382 Behavior similar to the "add" operation.
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383 </li>
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384
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385 <li><p><b>"len": </b>
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386 the <code>#</code> (length) operation.
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387
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388 If there is a metamethod,
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389 Luan calls it with the object as argument,
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390 and the result of the call
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391 (always adjusted to one value)
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392 is the result of the operation.
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393 If there is no metamethod but the object is a table,
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394 then Luan uses the table length operation (see <a href="#length">The Length Operator</a>).
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395 Otherwise, Luan raises an error.
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396 </li>
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397
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398 <li><p><b>"eq": </b>
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399 the <code>==</code> (equal) operation.
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400
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401 Behavior similar to the "add" operation,
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402 except that Luan will try a metamethod only when the values
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403 being compared are both tables
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404 and they are not primitively equal.
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405 The result of the call is always converted to a boolean.
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406 </li>
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407
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408 <li><p><b>"lt": </b>
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409 the <code>&lt;</code> (less than) operation.
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410
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411 Behavior similar to the "add" operation.
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412 The result of the call is always converted to a boolean.
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413 </li>
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414
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415 <li><p><b>"le": </b>
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416 the <code>&lt;=</code> (less equal) operation.
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417
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418 Unlike other operations,
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419 The less-equal operation can use two different events.
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420 First, Luan looks for the "<code>__le</code>" metamethod in both operands,
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421 like in the "lt" operation.
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422 If it cannot find such a metamethod,
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423 then it will try the "<code>__lt</code>" event,
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424 assuming that <code>a &lt;= b</code> is equivalent to <code>not (b &lt; a)</code>.
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425 As with the other comparison operators,
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426 the result is always a boolean.
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427 </li>
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428
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429 <li><p><b>"index": </b>
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430 The indexing access <code>table[key]</code>.
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431
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432 This event happens
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433 when <code>key</code> is not present in <code>table</code>.
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434 The metamethod is looked up in <code>table</code>.
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435
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436
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437 <p>
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438 Despite the name,
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439 the metamethod for this event can be any type.
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440 If it is a function,
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441 it is called with <code>table</code> and <code>key</code> as arguments.
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442 Otherwise
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443 the final result is the result of indexing this metamethod object with <code>key</code>.
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444 (This indexing is regular, not raw,
502
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445 and therefore can trigger another metamethod if the metamethod object is a table.)
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446 </li>
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447
502
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448 <li><p><b>"new_index": </b>
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449 The indexing assignment <code>table[key] = value</code>.
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450
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451 Like the index event,
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452 this event happens when
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453 when <code>key</code> is not present in <code>table</code>.
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454 The metamethod is looked up in <code>table</code>.
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455
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456
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457 <p>
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458 Like with indexing,
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459 the metamethod for this event can be either a function or a table.
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460 If it is a function,
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461 it is called with <code>table</code>, <code>key</code>, and <code>value</code> as arguments.
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462 If it is a table,
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463 Luan does an indexing assignment to this table with the same key and value.
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464 (This assignment is regular, not raw,
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465 and therefore can trigger another metamethod.)
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466
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467
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468 <p>
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469 Whenever there is a "new_index" metamethod,
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470 Luan does not perform the primitive assignment.
371
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471 (If necessary,
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472 the metamethod itself can call <a href="#Luan.raw_set"><code>raw_set</code></a>
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473 to do the assignment.)
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474 </li>
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475
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476 </ul>
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477
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478
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479
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480
562
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481 <h3 heading><a name="gc">Garbage Collection</a></h3>
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482
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483 <p>
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484 Luan uses Java's garbage collection.
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485
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486
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487
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488
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489
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490 <h2 heading><a name="lang">The Language</a></h2>
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491
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492 <p>
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493 This section describes the lexis, the syntax, and the semantics of Luan.
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494 In other words,
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495 this section describes
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496 which tokens are valid,
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497 how they can be combined,
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498 and what their combinations mean.
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499
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500
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501 <p>
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502 Language constructs will be explained using the usual extended BNF notation,
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503 in which
562
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504 {<em>a</em>}&nbsp;means&nbsp;0 or more <em>a</em>'s, and
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505 [<em>a</em>]&nbsp;means an optional <em>a</em>.
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506 Non-terminals are shown like non-terminal,
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507 keywords are shown like <b>kword</b>,
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508 and other terminal symbols are shown like &lsquo;<b>=</b>&rsquo;.
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509 The complete syntax of Luan can be found in <a href="#9">&sect;9</a>
371
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510 at the end of this manual.
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511
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512
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513
562
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514 <h3 heading><a name="lex">Lexical Conventions</a></h3>
380
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515
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516 <p>
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517 Luan ignores spaces and comments
371
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518 between lexical elements (tokens),
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519 except as delimiters between names and keywords.
685
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520 Luan considers the end of a line to be the end of a statement. This catches errors and encourages readability. If you want to continue a statement on another line, you can use a backslash followed by a newline which will be treated as white space.
562
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521
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522 <p>
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523 <em>Names</em>
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524 (also called <em>identifiers</em>)
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525 in Luan can be any string of letters,
371
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526 digits, and underscores,
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527 not beginning with a digit.
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528 Identifiers are used to name variables, table fields, and labels.
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529
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530
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531 <p>
562
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532 The following <em>keywords</em> are reserved
371
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533 and cannot be used as names:
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534
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535
562
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536 <pre>
371
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537 and break do else elseif end
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538 end_do end_for end_function end_if end_while
371
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539 false for function goto if in
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540 local nil not or repeat return
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541 then true until while
562
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542 </pre>
371
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543
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544 <p>
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545 Luan is a case-sensitive language:
562
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546 <code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
371
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547 are two different, valid names.
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548
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549
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550 <p>
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551 The following strings denote other tokens:
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552
562
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553 <pre>
371
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554 + - * / % ^ #
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555 &amp; ~ | &lt;&lt; &gt;&gt; //
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556 == ~= &lt;= &gt;= &lt; &gt; =
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557 ( ) { } [ ] ::
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558 ; : , . .. ...
562
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559 </pre>
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560
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561 <p>
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562 <em>Literal strings</em>
371
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563 can be delimited by matching single or double quotes,
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564 and can contain the following C-like escape sequences:
562
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565 '<code>\a</code>' (bell),
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566 '<code>\b</code>' (backspace),
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567 '<code>\f</code>' (form feed),
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568 '<code>\n</code>' (newline),
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569 '<code>\r</code>' (carriage return),
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570 '<code>\t</code>' (horizontal tab),
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571 '<code>\v</code>' (vertical tab),
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572 '<code>\\</code>' (backslash),
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573 '<code>\"</code>' (quotation mark [double quote]),
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574 and '<code>\'</code>' (apostrophe [single quote]).
371
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575 A backslash followed by a real newline
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576 results in a newline in the string.
562
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577 The escape sequence '<code>\z</code>' skips the following span
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578 of white-space characters,
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579 including line breaks;
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580 it is particularly useful to break and indent a long literal string
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581 into multiple lines without adding the newlines and spaces
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582 into the string contents.
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583
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584
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585 <p>
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586 Luan can specify any character in a literal string by its numerical value.
371
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587 This can be done
562
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588 with the escape sequence <code>\x<em>XX</em></code>,
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589 where <em>XX</em> is a sequence of exactly two hexadecimal digits,
793
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590 or with the escape sequence <code>\u<em>XXXX</em></code>,
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591 where <em>XXXX</em> is a sequence of exactly four hexadecimal digits,
562
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diff changeset
592 or with the escape sequence <code>\<em>ddd</em></code>,
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diff changeset
593 where <em>ddd</em> is a sequence of up to three decimal digits.
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594 (Note that if a decimal escape sequence is to be followed by a digit,
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595 it must be expressed using exactly three digits.)
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596
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597
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598 <p>
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599 Literal strings can also be defined using a long format
562
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diff changeset
600 enclosed by <em>long brackets</em>.
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601 We define an <em>opening long bracket of level <em>n</em></em> as an opening
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602 square bracket followed by <em>n</em> equal signs followed by another
371
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603 opening square bracket.
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604 So, an opening long bracket of level 0 is written as <code>[[</code>,
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605 an opening long bracket of level 1 is written as <code>[=[</code>,
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606 and so on.
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607 A <em>closing long bracket</em> is defined similarly;
371
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608 for instance,
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609 a closing long bracket of level 4 is written as <code>]====]</code>.
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610 A <em>long literal</em> starts with an opening long bracket of any level and
371
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611 ends at the first closing long bracket of the same level.
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612 It can contain any text except a closing bracket of the same level.
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613 Literals in this bracketed form can run for several lines,
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614 do not interpret any escape sequences,
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615 and ignore long brackets of any other level.
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616 Any kind of end-of-line sequence
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diff changeset
617 (carriage return, newline, carriage return followed by newline,
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618 or newline followed by carriage return)
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619 is converted to a simple newline.
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620
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diff changeset
621
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622 <p>
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623 Any character in a literal string not
371
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624 explicitly affected by the previous rules represents itself.
380
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625 However, Luan opens files for parsing in text mode,
371
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626 and the system file functions may have problems with
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627 some control characters.
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628 So, it is safer to represent
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629 non-text data as a quoted literal with
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630 explicit escape sequences for non-text characters.
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631
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632
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633 <p>
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634 For convenience,
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635 when the opening long bracket is immediately followed by a newline,
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636 the newline is not included in the string.
380
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diff changeset
637 As an example
371
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638 the five literal strings below denote the same string:
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639
562
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640 <pre>
371
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641 a = 'alo\n123"'
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642 a = "alo\n123\""
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643 a = '\97lo\10\04923"'
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644 a = [[alo
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645 123"]]
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646 a = [==[
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647 alo
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648 123"]==]
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diff changeset
649 </pre>
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diff changeset
650
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diff changeset
651 <p>
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diff changeset
652 A <em>numerical constant</em> (or <em>numeral</em>)
371
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653 can be written with an optional fractional part
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654 and an optional decimal exponent,
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655 marked by a letter '<code>e</code>' or '<code>E</code>'.
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656 Luan also accepts hexadecimal constants,
562
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657 which start with <code>0x</code> or <code>0X</code>.
371
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658 Hexadecimal constants also accept an optional fractional part
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659 plus an optional binary exponent,
562
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660 marked by a letter '<code>p</code>' or '<code>P</code>'.
371
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661 A numeric constant with a fractional dot or an exponent
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662 denotes a float;
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663 otherwise it denotes an integer.
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664 Examples of valid integer constants are
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665
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666 <pre>
371
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667 3 345 0xff 0xBEBADA
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668 </pre>
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diff changeset
669
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670 <p>
371
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671 Examples of valid float constants are
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672
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diff changeset
673 <pre>
371
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674 3.0 3.1416 314.16e-2 0.31416E1 34e1
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675 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562
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diff changeset
676 </pre>
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diff changeset
677
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diff changeset
678 <p>
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diff changeset
679 A <em>comment</em> starts with a double hyphen (<code>--</code>)
371
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680 anywhere outside a string.
562
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diff changeset
681 If the text immediately after <code>--</code> is not an opening long bracket,
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diff changeset
682 the comment is a <em>short comment</em>,
371
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683 which runs until the end of the line.
562
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diff changeset
684 Otherwise, it is a <em>long comment</em>,
371
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diff changeset
685 which runs until the corresponding closing long bracket.
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diff changeset
686 Long comments are frequently used to disable code temporarily.
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parents:
diff changeset
687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
688
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
690
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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691
562
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692 <h3 heading><a name="vars">Variables</a></h3>
371
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693
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parents:
diff changeset
694 <p>
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diff changeset
695 Variables are places that store values.
380
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696 There are three kinds of variables in Luan:
371
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697 global variables, local variables, and table fields.
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parents:
diff changeset
698
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
699 <p>
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diff changeset
700 A single name can denote a global variable or a local variable
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701 (or a function's formal parameter,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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702 which is a particular kind of local variable):
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703
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704 <pre>
371
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705 var ::= Name
562
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diff changeset
706 </pre>
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diff changeset
707
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708 <p>
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diff changeset
709 Name denotes identifiers, as defined in <a href="#lex">Lexical Conventions</a>.
371
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parents:
diff changeset
710
512
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parents: 505
diff changeset
711 <p>
562
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diff changeset
712 Local variables are <em>lexically scoped</em>:
371
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713 local variables can be freely accessed by functions
464
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diff changeset
714 defined inside their scope (see <a href="#visibility">Visibility Rules</a>).
371
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parents:
diff changeset
715
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parents:
diff changeset
716
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
717 <p>
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parents:
diff changeset
718 Before the first assignment to a variable, its value is <b>nil</b>.
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parents:
diff changeset
719
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parents:
diff changeset
720 <p>
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parents:
diff changeset
721 Square brackets are used to index a table:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
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722
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diff changeset
723 <pre>
371
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724 var ::= prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo;
562
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diff changeset
725 </pre>
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diff changeset
726
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diff changeset
727 <p>
371
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728 The meaning of accesses to table fields can be changed via metatables.
562
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diff changeset
729 An access to an indexed variable <code>t[i]</code> is equivalent to
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diff changeset
730 a call <code>gettable_event(t,i)</code>.
464
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diff changeset
731 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562
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diff changeset
732 <code>gettable_event</code> function.
380
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733 This function is not defined or callable in Luan.
371
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diff changeset
734 We use it here only for explanatory purposes.)
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parents:
diff changeset
735
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parents:
diff changeset
736
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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737 <p>
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diff changeset
738 The syntax <code>var.Name</code> is just syntactic sugar for
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diff changeset
739 <code>var["Name"]</code>:
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diff changeset
740
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diff changeset
741 <pre>
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742 var ::= prefixexp &lsquo;<b>.</b>&rsquo; Name
562
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diff changeset
743 </pre>
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diff changeset
744
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diff changeset
745 <p>
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diff changeset
746 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>
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747 is equivalent to <code>_ENV.x</code>.
371
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748 Due to the way that chunks are compiled,
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diff changeset
749 <code>_ENV</code> is never a global name (see <a href="#env">Environments</a>).
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750
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diff changeset
751
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diff changeset
752
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diff changeset
753
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diff changeset
754
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diff changeset
755 <h3 heading><a name="stmts">Statements</a></h3>
389
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diff changeset
756
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757 <p>
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758 Luan supports an almost conventional set of statements,
371
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759 similar to those in Pascal or C.
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760 This set includes
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761 assignments, control structures, function calls,
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762 and variable declarations.
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763
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diff changeset
764
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765
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766 <h4 heading><a name="blocks">Blocks</a></h4>
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767
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diff changeset
768 <p>
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diff changeset
769 A block is a list of statements,
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770 which are executed sequentially:
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771
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diff changeset
772 <pre>
371
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773 block ::= {stat}
562
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diff changeset
774 </pre>
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diff changeset
775
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diff changeset
776 <p>
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diff changeset
777 Luan has <em>empty statements</em>
371
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778 that allow you to separate statements with semicolons,
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779 start a block with a semicolon
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780 or write two semicolons in sequence:
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781
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diff changeset
782 <pre>
371
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783 stat ::= &lsquo;<b>;</b>&rsquo;
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diff changeset
784 </pre>
371
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785
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diff changeset
786 <p>
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787 A block can be explicitly delimited to produce a single statement:
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788
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diff changeset
789 <pre>
1092
a26fbde7ee28 documentation
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diff changeset
790 stat ::= <b>do</b> block end_do
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parents: 1090
diff changeset
791 end_do ::= <b>end_do</b> | <b>end</b>
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diff changeset
792 </pre>
389
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793
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794 <p>
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diff changeset
795 Explicit blocks are useful
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796 to control the scope of variable declarations.
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diff changeset
797 Explicit blocks are also sometimes used to
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diff changeset
798 add a <b>return</b> statement in the middle
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799 of another block (see <a href="#control">Control Structures</a>).
371
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800
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parents:
diff changeset
801
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
802
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
804
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diff changeset
805 <h4 heading><a name="chunks">Chunks</a></h4>
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diff changeset
806
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807 <p>
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diff changeset
808 The unit of compilation of Luan is called a <em>chunk</em>.
371
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809 Syntactically,
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810 a chunk is simply a block:
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diff changeset
811
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diff changeset
812 <pre>
371
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813 chunk ::= block
562
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diff changeset
814 </pre>
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diff changeset
815
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816 <p>
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diff changeset
817 Luan handles a chunk as the body of an anonymous function
371
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818 with a variable number of arguments
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819 (see <a href="#fn_def">Function Definitions</a>).
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820 As such, chunks can define local variables,
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821 receive arguments, and return values.
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diff changeset
822
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diff changeset
823
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diff changeset
824 <p>
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diff changeset
825 A chunk can be stored in a file or in a string inside the host program.
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826 To execute a chunk,
562
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diff changeset
827 Luan first <em>loads</em> it,
395
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diff changeset
828 compiling the chunk's code,
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diff changeset
829 and then Luan executes the compiled code.
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diff changeset
830
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diff changeset
831
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diff changeset
832
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diff changeset
833
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diff changeset
834
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diff changeset
835 <h4 heading><a name="assignment">Assignment</a></h4>
395
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diff changeset
836
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diff changeset
837 <p>
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diff changeset
838 Luan allows multiple assignments.
371
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839 Therefore, the syntax for assignment
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840 defines a list of variables on the left side
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diff changeset
841 and a list of expressions on the right side.
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diff changeset
842 The elements in both lists are separated by commas:
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diff changeset
843
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diff changeset
844 <pre>
371
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diff changeset
845 stat ::= varlist &lsquo;<b>=</b>&rsquo; explist
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parents:
diff changeset
846 varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
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diff changeset
847 explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
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diff changeset
848 </pre>
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diff changeset
849
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850 <p>
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diff changeset
851 Expressions are discussed in <a href="#expressions">Expressions</a>.
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diff changeset
852
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parents:
diff changeset
853
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
854 <p>
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diff changeset
855 Before the assignment,
562
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diff changeset
856 the list of values is <em>adjusted</em> to the length of
371
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857 the list of variables.
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diff changeset
858 If there are more values than needed,
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859 the excess values are thrown away.
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diff changeset
860 If there are fewer values than needed,
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861 the list is extended with as many <b>nil</b>'s as needed.
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862 If the list of expressions ends with a function call,
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diff changeset
863 then all values returned by that call enter the list of values,
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864 before the adjustment
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diff changeset
865 (except when the call is enclosed in parentheses; see <a href="#expressions">Expressions</a>).
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866
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diff changeset
867
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
868 <p>
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parents:
diff changeset
869 The assignment statement first evaluates all its expressions
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diff changeset
870 and only then the assignments are performed.
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871 Thus the code
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872
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diff changeset
873 <pre>
371
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874 i = 3
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875 i, a[i] = i+1, 20
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876 </pre>
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diff changeset
877
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878 <p>
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diff changeset
879 sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
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880 because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
371
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881 before it is assigned&nbsp;4.
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diff changeset
882 Similarly, the line
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883
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diff changeset
884 <pre>
371
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diff changeset
885 x, y = y, x
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diff changeset
886 </pre>
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diff changeset
887
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888 <p>
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diff changeset
889 exchanges the values of <code>x</code> and <code>y</code>,
371
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890 and
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diff changeset
891
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diff changeset
892 <pre>
371
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diff changeset
893 x, y, z = y, z, x
562
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diff changeset
894 </pre>
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diff changeset
895
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diff changeset
896 <p>
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diff changeset
897 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
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898
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parents:
diff changeset
899
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diff changeset
900 <p>
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901 The meaning of assignments to global variables
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902 and table fields can be changed via metatables.
562
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903 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
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diff changeset
904 <code>settable_event(t,i,val)</code>.
464
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905 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562
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diff changeset
906 <code>settable_event</code> function.
395
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907 This function is not defined or callable in Luan.
371
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908 We use it here only for explanatory purposes.)
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909
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parents:
diff changeset
910
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911 <p>
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diff changeset
912 An assignment to a global name <code>x = val</code>
371
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913 is equivalent to the assignment
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diff changeset
914 <code>_ENV.x = val</code> (see <a href="#env">Environments</a>).
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915 Global names are only available when <code>_ENV</code> is defined.
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916
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diff changeset
917
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918
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diff changeset
919 <h4 heading><a name="control">Control Structures</a></h4>
395
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920
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921 <p>
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922 The control structures
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923 <b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and
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924 familiar syntax:
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925
562
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diff changeset
926 <pre>
1092
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927 stat ::= <b>while</b> exp <b>do</b> block end_while
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928 stat ::= <b>repeat</b> block <b>until</b> exp
1092
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diff changeset
929 stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] end_if
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parents: 1090
diff changeset
930 end_while ::= <b>end_while</b> | <b>end</b>
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diff changeset
931 end_if ::= <b>end_if</b> | <b>end</b>
562
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diff changeset
932 </pre>
395
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diff changeset
933
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934 <p>
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eddf7c73373b fix references in the manual
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diff changeset
935 Luan also has a <b>for</b> statement (see <a href="#for">For Statement</a>).
371
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936
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diff changeset
937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
938 <p>
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939 The condition expression of a
395
a7cb58532846 work on manual
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diff changeset
940 control structure must be a boolean.
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diff changeset
941 Any other value type will produce an error.
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diff changeset
942 This helps catch errors and makes code more readable.
371
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diff changeset
943
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diff changeset
944
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diff changeset
945 <p>
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diff changeset
946 In the <b>repeat</b>&ndash;<b>until</b> loop,
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947 the inner block does not end at the <b>until</b> keyword,
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948 but only after the condition.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
949 So, the condition can refer to local variables
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950 declared inside the loop block.
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diff changeset
951
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parents:
diff changeset
952
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diff changeset
953 <p>
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diff changeset
954 The <b>break</b> statement terminates the execution of a
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955 <b>while</b>, <b>repeat</b>, or <b>for</b> loop,
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diff changeset
956 skipping to the next statement after the loop:
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diff changeset
957
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958
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diff changeset
959 <pre>
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960 stat ::= <b>break</b>
562
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diff changeset
961 </pre>
395
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diff changeset
962
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diff changeset
963 <p>
371
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964 A <b>break</b> ends the innermost enclosing loop.
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965
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diff changeset
966
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diff changeset
967 <p>
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diff changeset
968 The <b>return</b> statement is used to return values
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diff changeset
969 from a function or a chunk
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970 (which is an anonymous function).
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diff changeset
971
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diff changeset
972 Functions can return more than one value,
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diff changeset
973 so the syntax for the <b>return</b> statement is
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diff changeset
974
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diff changeset
975 <pre>
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diff changeset
976 stat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
562
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diff changeset
977 </pre>
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parents: 556
diff changeset
978
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parents: 556
diff changeset
979
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parents: 556
diff changeset
980
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diff changeset
981
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diff changeset
982 <h4 heading><a name="for">For Statement</a></h4>
395
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diff changeset
983
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diff changeset
984 <p>
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diff changeset
985 The <b>for</b> statement works over functions,
562
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diff changeset
986 called <em>iterators</em>.
395
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diff changeset
987 On each iteration, the iterator function is called to produce a new value,
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diff changeset
988 stopping when this new value is <b>nil</b>.
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diff changeset
989 The <b>for</b> loop has the following syntax:
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diff changeset
990
562
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diff changeset
991 <pre>
1092
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parents: 1090
diff changeset
992 stat ::= <b>for</b> namelist <b>in</b> exp <b>do</b> block end_for
395
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diff changeset
993 namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
1092
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diff changeset
994 end_for ::= <b>end_for</b> | <b>end</b>
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995 </pre>
395
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diff changeset
996
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diff changeset
997 <p>
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diff changeset
998 A <b>for</b> statement like
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diff changeset
999
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1000 <pre>
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1001 for <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> in <em>exp</em> do <em>block</em> end
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1002 </pre>
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diff changeset
1003
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1004 <p>
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1005 is equivalent to the code:
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1006
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1007 <pre>
371
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1008 do
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diff changeset
1009 local <em>f</em> = <em>exp</em>
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1010 while true do
562
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diff changeset
1011 local <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> = <em>f</em>()
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1012 if <em>var_1</em> == nil then break end
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1013 <em>block</em>
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1014 end
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1015 end
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1016 </pre>
371
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diff changeset
1017
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diff changeset
1018 <p>
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diff changeset
1019 Note the following:
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parents:
diff changeset
1020
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diff changeset
1021 <ul>
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diff changeset
1022
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1023 <li>
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1024 <code><em>exp</em></code> is evaluated only once.
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diff changeset
1025 Its result is an <em>iterator</em> function.
371
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diff changeset
1026 </li>
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parents:
diff changeset
1027
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1028 <li>
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diff changeset
1029 <code><em>f</em></code> is an invisible variable.
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diff changeset
1030 The name is here for explanatory purposes only.
371
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1031 </li>
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parents:
diff changeset
1032
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1033 <li>
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1034 You can use <b>break</b> to exit a <b>for</b> loop.
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1035 </li>
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diff changeset
1036
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1037 <li>
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diff changeset
1038 The loop variables <code><em>var_i</em></code> are local to the loop;
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1039 you cannot use their values after the <b>for</b> ends.
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diff changeset
1040 If you need these values,
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diff changeset
1041 then assign them to other variables before breaking or exiting the loop.
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diff changeset
1042 </li>
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diff changeset
1043
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diff changeset
1044 </ul>
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parents:
diff changeset
1045
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1046
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1048
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diff changeset
1049 <h4 heading><a name="fn_stmt">Function Calls as Statements</a></h4>
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1050
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diff changeset
1051 <p>
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1052 To allow possible side-effects,
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diff changeset
1053 function calls can be executed as statements:
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diff changeset
1054
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diff changeset
1055 <pre>
371
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diff changeset
1056 stat ::= functioncall
562
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diff changeset
1057 </pre>
395
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diff changeset
1058
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diff changeset
1059 <p>
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1060 In this case, all returned values are thrown away.
464
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1061 Function calls are explained in <a href="#fn_calls">Function Calls</a>.
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1062
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diff changeset
1063
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diff changeset
1064
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diff changeset
1065 <h4 heading><a name="local_stmt">Local Declarations</a></h4>
395
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diff changeset
1066
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diff changeset
1067 <p>
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diff changeset
1068 Local variables can be declared anywhere inside a block.
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parents:
diff changeset
1069 The declaration can include an initial assignment:
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diff changeset
1070
562
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1071 <pre>
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1072 stat ::= <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist]
562
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diff changeset
1073 </pre>
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diff changeset
1074
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1075 <p>
371
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1076 If present, an initial assignment has the same semantics
464
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1077 of a multiple assignment (see <a href="#assignment">Assignment</a>).
371
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1078 Otherwise, all variables are initialized with <b>nil</b>.
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parents:
diff changeset
1079
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parents:
diff changeset
1080
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diff changeset
1081 <p>
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1082 A chunk is also a block (see <a href="#chunks">Chunks</a>),
371
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1083 and so local variables can be declared in a chunk outside any explicit block.
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diff changeset
1084
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diff changeset
1085
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1086 <p>
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diff changeset
1087 The visibility rules for local variables are explained in <a href="#visibility">Visibility Rules</a>.
371
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1088
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diff changeset
1089
562
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diff changeset
1090 <h4 heading><a name="template_stmt">Template Statements</a></h4>
465
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diff changeset
1091
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diff changeset
1092 <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>
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diff changeset
1093
562
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diff changeset
1094 <pre><%=Html.encode[[
465
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diff changeset
1095 local name = "Bob"
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diff changeset
1096 %>
469
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diff changeset
1097 Hello <%= name %>!
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diff changeset
1098 Bye <%= name %>.
465
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diff changeset
1099 <%
562
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diff changeset
1100 ]]%></pre>
465
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parents: 464
diff changeset
1101
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diff changeset
1102 <p>is equivalent to the code:</p>
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diff changeset
1103
562
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diff changeset
1104 <pre><%=Html.encode[[
465
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diff changeset
1105 local name = "Bob"
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
1106 require("luan:Io.luan").stdout.write( %>
469
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parents: 468
diff changeset
1107 Hello <%= name %>!
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1108 Bye <%= name %>.
465
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diff changeset
1109 <% )
562
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diff changeset
1110 ]]%></pre>
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parents: 556
diff changeset
1111
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parents: 556
diff changeset
1112
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parents: 556
diff changeset
1113
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diff changeset
1114 <h3 heading><a name="expressions">Expressions</a></h3>
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diff changeset
1115
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1116 <p>
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1117 The basic expressions in Luan are the following:
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1118
562
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1119 <pre>
371
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diff changeset
1120 exp ::= prefixexp
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diff changeset
1121 exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
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diff changeset
1122 exp ::= Numeral
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diff changeset
1123 exp ::= LiteralString
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diff changeset
1124 exp ::= functiondef
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diff changeset
1125 exp ::= tableconstructor
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parents:
diff changeset
1126 exp ::= &lsquo;<b>...</b>&rsquo;
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diff changeset
1127 exp ::= exp binop exp
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diff changeset
1128 exp ::= unop exp
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diff changeset
1129 prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
562
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diff changeset
1130 </pre>
371
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parents:
diff changeset
1131
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diff changeset
1132 <p>
464
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parents: 429
diff changeset
1133 Numerals and literal strings are explained in <a href="#lex">Lexical Conventions</a>;
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1134 variables are explained in <a href="#vars">Variables</a>;
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1135 function definitions are explained in <a href="#fn_def">Function Definitions</a>;
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diff changeset
1136 function calls are explained in <a href="#fn_calls">Function Calls</a>;
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diff changeset
1137 table constructors are explained in <a href="#constructors">Table Constructors</a>.
371
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1138 Vararg expressions,
562
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diff changeset
1139 denoted by three dots ('<code>...</code>'), can only be used when
371
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1140 directly inside a vararg function;
464
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diff changeset
1141 they are explained in <a href="#fn_def">Function Definitions</a>.
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diff changeset
1142
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diff changeset
1143
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1144 <p>
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1145 Binary operators comprise arithmetic operators (see <a href="#arithmetic">Arithmetic Operators</a>),
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parents: 429
diff changeset
1146 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
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diff changeset
1147 and the concatenation operator (see <a href="#concatenation">Concatenation</a>).
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diff changeset
1148 Unary operators comprise the unary minus (see <a href="#arithmetic">Arithmetic Operators</a>),
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parents: 429
diff changeset
1149 the unary logical <b>not</b> (see <a href="#logical_ops">Logical Operators</a>),
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parents: 429
diff changeset
1150 and the unary <em>length operator</em> (see <a href="#length">The Length Operator</a>).
371
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parents:
diff changeset
1151
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parents:
diff changeset
1152
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1153 <p>
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parents:
diff changeset
1154 Both function calls and vararg expressions can result in multiple values.
464
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diff changeset
1155 If a function call is used as a statement (see <a href="#fn_stmt">Function Calls as Statements</a>),
371
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diff changeset
1156 then its return list is adjusted to zero elements,
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parents:
diff changeset
1157 thus discarding all returned values.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1158 If an expression is used as the last (or the only) element
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diff changeset
1159 of a list of expressions,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1160 then no adjustment is made
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diff changeset
1161 (unless the expression is enclosed in parentheses).
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1162 In all other contexts,
395
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diff changeset
1163 Luan adjusts the result list to one element,
371
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diff changeset
1164 either discarding all values except the first one
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1165 or adding a single <b>nil</b> if there are no values.
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parents:
diff changeset
1166
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parents:
diff changeset
1167
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parents:
diff changeset
1168 <p>
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parents:
diff changeset
1169 Here are some examples:
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1170
562
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diff changeset
1171 <pre>
371
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diff changeset
1172 f() -- adjusted to 0 results
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diff changeset
1173 g(f(), x) -- f() is adjusted to 1 result
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diff changeset
1174 g(x, f()) -- g gets x plus all results from f()
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parents:
diff changeset
1175 a,b,c = f(), x -- f() is adjusted to 1 result (c gets nil)
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parents:
diff changeset
1176 a,b = ... -- a gets the first vararg parameter, b gets
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parents:
diff changeset
1177 -- the second (both a and b can get nil if there
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parents:
diff changeset
1178 -- is no corresponding vararg parameter)
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parents:
diff changeset
1179
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parents:
diff changeset
1180 a,b,c = x, f() -- f() is adjusted to 2 results
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parents:
diff changeset
1181 a,b,c = f() -- f() is adjusted to 3 results
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parents:
diff changeset
1182 return f() -- returns all results from f()
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diff changeset
1183 return ... -- returns all received vararg parameters
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1184 return x,y,f() -- returns x, y, and all results from f()
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1185 {f()} -- creates a list with all results from f()
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1186 {...} -- creates a list with all vararg parameters
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1187 {f(), nil} -- f() is adjusted to 1 result
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1188 </pre>
371
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diff changeset
1189
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1190 <p>
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1191 Any expression enclosed in parentheses always results in only one value.
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1192 Thus,
562
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1193 <code>(f(x,y,z))</code> is always a single value,
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1194 even if <code>f</code> returns several values.
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diff changeset
1195 (The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
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1196 or <b>nil</b> if <code>f</code> does not return any values.)
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diff changeset
1197
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diff changeset
1198
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diff changeset
1199
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diff changeset
1200 <h4 heading><a name="arithmetic">Arithmetic Operators</a></h4>
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1201
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1202 <p>
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1203 Luan supports the following arithmetic operators:
371
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1204
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1205 <ul>
562
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1206 <li><b><code>+</code>: </b>addition</li>
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1207 <li><b><code>-</code>: </b>subtraction</li>
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1208 <li><b><code>*</code>: </b>multiplication</li>
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1209 <li><b><code>/</code>: </b>division</li>
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1210 <li><b><code>%</code>: </b>modulo</li>
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1211 <li><b><code>^</code>: </b>exponentiation</li>
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1212 <li><b><code>-</code>: </b>unary minus</li>
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1213 </ul>
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diff changeset
1214
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1215 <p>
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1216 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
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1217
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1218 <p>
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diff changeset
1219 Modulo is defined as the remainder of a division
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1220 that rounds the quotient towards minus infinite (floor division).
395
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1221 (The Java modulo operator is not used.)
371
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1222
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diff changeset
1223
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1224
562
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1225 <h4 heading><a name="conversions">Coercions and Conversions</a></h4>
396
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1226
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diff changeset
1227 <p>
465
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1228 Luan generally avoids automatic conversions.
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diff changeset
1229 String concatenation automatically converts all of its arguments to strings.
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diff changeset
1230
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1231 <p>
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1232 Luan provides library functions for explicit type conversions.
371
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1233
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1234
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diff changeset
1235
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diff changeset
1236
562
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1237 <h4 heading><a name="relational">Relational Operators</a></h4>
396
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1238
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1239 <p>
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1240 Luan supports the following relational operators:
371
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1241
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diff changeset
1242 <ul>
562
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diff changeset
1243 <li><b><code>==</code>: </b>equality</li>
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diff changeset
1244 <li><b><code>~=</code>: </b>inequality</li>
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diff changeset
1245 <li><b><code>&lt;</code>: </b>less than</li>
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diff changeset
1246 <li><b><code>&gt;</code>: </b>greater than</li>
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1247 <li><b><code>&lt;=</code>: </b>less or equal</li>
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1248 <li><b><code>&gt;=</code>: </b>greater or equal</li>
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diff changeset
1249 </ul><p>
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diff changeset
1250 These operators always result in <b>false</b> or <b>true</b>.
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diff changeset
1251
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1253 <p>
562
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diff changeset
1254 Equality (<code>==</code>) first compares the type of its operands.
371
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1255 If the types are different, then the result is <b>false</b>.
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1256 Otherwise, the values of the operands are compared.
396
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diff changeset
1257 Strings, numbers, and binary values are compared in the obvious way (by value).
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diff changeset
1258
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diff changeset
1259 <p>
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diff changeset
1260 Tables
371
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diff changeset
1261 are compared by reference:
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diff changeset
1262 two objects are considered equal only if they are the same object.
396
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diff changeset
1263 Every time you create a new table,
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1264 it is different from any previously existing table.
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1265 Closures are also compared by reference.
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1266
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diff changeset
1267 <p>
417
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diff changeset
1268 You can change the way that Luan compares tables
464
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diff changeset
1269 by using the "eq" metamethod (see <a href="#meta">Metatables and Metamethods</a>).
371
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1270
396
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diff changeset
1271 <p>
562
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diff changeset
1272 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
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diff changeset
1273
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diff changeset
1274 <p>
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diff changeset
1275 Equality comparisons do not convert strings to numbers
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diff changeset
1276 or vice versa.
562
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diff changeset
1277 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
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diff changeset
1278 and <code>t[0]</code> and <code>t["0"]</code> denote different
371
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diff changeset
1279 entries in a table.
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diff changeset
1280
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1281
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diff changeset
1282 <p>
562
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diff changeset
1283 The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
371
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diff changeset
1284
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parents:
diff changeset
1285
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1286 <p>
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diff changeset
1287 The order operators work as follows.
396
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diff changeset
1288
371
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diff changeset
1289 If both arguments are numbers,
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diff changeset
1290 then they are compared following
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diff changeset
1291 the usual rule for binary operations.
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diff changeset
1292 Otherwise, if both arguments are strings,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1293 then their values are compared according to the current locale.
396
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diff changeset
1294 Otherwise, Luan tries to call the "lt" or the "le"
464
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diff changeset
1295 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562
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diff changeset
1296 A comparison <code>a &gt; b</code> is translated to <code>b &lt; a</code>
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diff changeset
1297 and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
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diff changeset
1298
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diff changeset
1299
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diff changeset
1300
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diff changeset
1301
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diff changeset
1302
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diff changeset
1303 <h4 heading><a name="logical_ops">Logical Operators</a></h4>
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1304
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1305 <p>
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diff changeset
1306 The logical operators in Luan are
371
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1307 <b>and</b>, <b>or</b>, and <b>not</b>.
396
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1308 The <b>and</b> and <b>or</b> operators consider both <b>false</b> and <b>nil</b> as false
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diff changeset
1309 and anything else as true.
464
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diff changeset
1310 Like the control structures (see <a href="#control">Control Structures</a>),
396
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1311 the <b>not</b> operator requires a boolean value.
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diff changeset
1312
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diff changeset
1313 <p>
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diff changeset
1314 The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>.
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diff changeset
1315 The conjunction operator <b>and</b> returns its first argument
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diff changeset
1316 if this value is <b>false</b> or <b>nil</b>;
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1317 otherwise, <b>and</b> returns its second argument.
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diff changeset
1318 The disjunction operator <b>or</b> returns its first argument
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diff changeset
1319 if this value is different from <b>nil</b> and <b>false</b>;
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1320 otherwise, <b>or</b> returns its second argument.
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diff changeset
1321 Both <b>and</b> and <b>or</b> use short-circuit evaluation;
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1322 that is,
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diff changeset
1323 the second operand is evaluated only if necessary.
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diff changeset
1324 Here are some examples:
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diff changeset
1325
562
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diff changeset
1326 <pre>
371
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parents:
diff changeset
1327 10 or 20 --&gt; 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1328 10 or error() --&gt; 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1329 nil or "a" --&gt; "a"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1330 nil and 10 --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1331 false and error() --&gt; false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1332 false and nil --&gt; false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1333 false or nil --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1334 10 and 20 --&gt; 20
562
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diff changeset
1335 </pre>
396
ba8b0aae6453 work on manual;
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diff changeset
1336
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diff changeset
1337 <p>
371
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diff changeset
1338 (In this manual,
562
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diff changeset
1339 <code>--&gt;</code> indicates the result of the preceding expression.)
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parents: 556
diff changeset
1340
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1341
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parents: 556
diff changeset
1342
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1343 <h4 heading><a name="concatenation">Concatenation</a></h4>
396
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diff changeset
1344
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diff changeset
1345 <p>
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diff changeset
1346 The string concatenation operator in Luan is
562
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diff changeset
1347 denoted by two dots ('<code>..</code>').
396
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diff changeset
1348 All operands are converted to strings.
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diff changeset
1349
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diff changeset
1350
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diff changeset
1351
562
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diff changeset
1352 <h4 heading><a name="length">The Length Operator</a></h4>
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diff changeset
1353
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diff changeset
1354 <p>
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diff changeset
1355 The length operator is denoted by the unary prefix operator <code>#</code>.
396
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diff changeset
1356 The length of a string is its number of characters.
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diff changeset
1357 The length of a binary is its number of bytes.
371
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diff changeset
1358
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1359
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1360 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1361 A program can modify the behavior of the length operator for
562
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diff changeset
1362 any table through the <code>__len</code> metamethod (see <a href="#meta">Metatables and Metamethods</a>).
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diff changeset
1363
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parents: 556
diff changeset
1364
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parents: 556
diff changeset
1365 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1366 Unless a <code>__len</code> metamethod is given,
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1367 the length of a table <code>t</code> is defined
396
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diff changeset
1368 as the number of elements in <em>sequence</em>,
371
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diff changeset
1369 that is,
396
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diff changeset
1370 the size of the set of its positive numeric keys is equal to <em>{1..n}</em>
371
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diff changeset
1371 for some non-negative integer <em>n</em>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1372 In that case, <em>n</em> is its length.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1373 Note that a table like
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1374
562
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diff changeset
1375 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1376 {10, 20, nil, 40}
562
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diff changeset
1377 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1378
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1379 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1380 has a length of <code>2</code>, because that is the last key in sequence.
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1381
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parents: 556
diff changeset
1382
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1383
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1384
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1385
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1386 <h4 heading><a name="precedence">Precedence</a></h4>
396
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diff changeset
1387
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diff changeset
1388 <p>
ba8b0aae6453 work on manual;
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diff changeset
1389 Operator precedence in Luan follows the table below,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1390 from lower to higher priority:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1391
562
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diff changeset
1392 <pre>
371
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parents:
diff changeset
1393 or
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1394 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1395 &lt; &gt; &lt;= &gt;= ~= ==
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parents:
diff changeset
1396 ..
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1397 + -
396
ba8b0aae6453 work on manual;
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parents: 395
diff changeset
1398 * / %
ba8b0aae6453 work on manual;
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parents: 395
diff changeset
1399 unary operators (not # -)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1400 ^
562
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parents: 556
diff changeset
1401 </pre>
396
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parents: 395
diff changeset
1402
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parents: 395
diff changeset
1403 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1404 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1405 you can use parentheses to change the precedences of an expression.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1406 The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
371
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parents:
diff changeset
1407 operators are right associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1408 All other binary operators are left associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1409
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1410
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
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parents:
diff changeset
1413
562
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diff changeset
1414 <h4 heading><a name="constructors">Table Constructors</a></h4>
396
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diff changeset
1415
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diff changeset
1416 <p>
371
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parents:
diff changeset
1417 Table constructors are expressions that create tables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1418 Every time a constructor is evaluated, a new table is created.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1419 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
1420 or to create a table and initialize some of its fields.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1421 The general syntax for constructors is
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1422
562
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diff changeset
1423 <pre>
604
b73f005f3735 table constructor now uses end_of_line as a delimiter
Franklin Schmidt <fschmidt@gmail.com>
parents: 589
diff changeset
1424 tableconstructor ::= &lsquo;<b>{</b>&rsquo; fieldlist &lsquo;<b>}</b>&rsquo;
b73f005f3735 table constructor now uses end_of_line as a delimiter
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parents: 589
diff changeset
1425 fieldlist ::= [field] {fieldsep [field]}
371
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parents:
diff changeset
1426 field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
604
b73f005f3735 table constructor now uses end_of_line as a delimiter
Franklin Schmidt <fschmidt@gmail.com>
parents: 589
diff changeset
1427 fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo; | <b>end_of_line</b>
562
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parents: 556
diff changeset
1428 </pre>
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parents: 556
diff changeset
1429
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1430 <p>
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parents: 556
diff changeset
1431 Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1432 with key <code>exp1</code> and value <code>exp2</code>.
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parents: 556
diff changeset
1433 A field of the form <code>name = exp</code> is equivalent to
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parents: 556
diff changeset
1434 <code>["name"] = exp</code>.
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parents: 556
diff changeset
1435 Finally, fields of the form <code>exp</code> are equivalent to
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diff changeset
1436 <code>[i] = exp</code>, where <code>i</code> are consecutive integers
371
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parents:
diff changeset
1437 starting with 1.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1438 Fields in the other formats do not affect this counting.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1439 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1440
562
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diff changeset
1441 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1442 a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
562
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parents: 556
diff changeset
1443 </pre>
396
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parents: 395
diff changeset
1444
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diff changeset
1445 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1446 is equivalent to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1447
562
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parents: 556
diff changeset
1448 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1449 do
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parents:
diff changeset
1450 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1451 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1452 t[1] = "x" -- 1st exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1453 t[2] = "y" -- 2nd exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1454 t.x = 1 -- t["x"] = 1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1455 t[3] = f(x) -- 3rd exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1456 t[30] = 23
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1457 t[4] = 45 -- 4th exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1458 a = t
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1459 end
562
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diff changeset
1460 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1461
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1462 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1463 The order of the assignments in a constructor is undefined.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1464 (This order would be relevant only when there are repeated keys.)
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parents:
diff changeset
1465
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1466
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1467 <p>
562
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parents: 556
diff changeset
1468 If the last field in the list has the form <code>exp</code>
371
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parents:
diff changeset
1469 and the expression is a function call or a vararg expression,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1470 then all values returned by this expression enter the list consecutively
464
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1471 (see <a href="#fn_calls">Function Calls</a>).
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1472
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1473
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1474 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1475 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
1476 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
1477
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1479
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
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1482 <h4 heading><a name="fn_calls">Function Calls</a></h4>
417
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diff changeset
1483
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diff changeset
1484 <p>
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parents: 396
diff changeset
1485 A function call in Luan has the following syntax:
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parents: 396
diff changeset
1486
562
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diff changeset
1487 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1488 functioncall ::= prefixexp args
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1489 </pre>
417
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parents: 396
diff changeset
1490
a40e99cf0b0b work on manual
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diff changeset
1491 <p>
371
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diff changeset
1492 In a function call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1493 first prefixexp and args are evaluated.
685
1e4b0bc0202d update documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 642
diff changeset
1494 The value of prefixexp must have type <em>function</em>.
1e4b0bc0202d update documentation
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parents: 642
diff changeset
1495 This function is called
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1496 with the given arguments.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1497
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1499 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1500 Arguments have the following syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1501
562
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parents: 556
diff changeset
1502 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1503 args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1504 args ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1505 args ::= LiteralString
562
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parents: 556
diff changeset
1506 </pre>
417
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parents: 396
diff changeset
1507
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1508 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1509 All argument expressions are evaluated before the call.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1510 A call of the form <code>f{<em>fields</em>}</code> is
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1511 syntactic sugar for <code>f({<em>fields</em>})</code>;
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
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1512 that is, the argument list is a single new table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1513 A call of the form <code>f'<em>string</em>'</code>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1514 (or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>)
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1515 is syntactic sugar for <code>f('<em>string</em>')</code>;
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1516 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
1517
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1518
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1519
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1520
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1521 <h4 heading><a name="fn_def">Function Definitions</a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1522
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1523 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1524 The syntax for function definition is
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1525
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1526 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1527 functiondef ::= <b>function</b> funcbody
1092
a26fbde7ee28 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 1090
diff changeset
1528 funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block end_function
a26fbde7ee28 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 1090
diff changeset
1529 end_function ::= <b>end_function</b> | <b>end</b>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1530 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1531
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1532 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1533 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
1534
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1535 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1536 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
1537 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
1538 funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1539 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1540
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1541 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1542 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1543
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1544 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1545 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1546 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1547
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1548 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1549 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1550
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1551 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1552 f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1553 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1554
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1555 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1556 The statement
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>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1559 function t.a.b.c.f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1560 </pre>
417
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1561
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1562 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1563 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1564
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1565 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1566 t.a.b.c.f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1567 </pre>
417
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1568
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1569 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1570 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1571
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1572 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1573 local function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1574 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1575
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1576 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1577 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1578
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1579 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1580 local f; f = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1581 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1582
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 396
diff changeset
1583 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1584 not to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1585
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1586 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1587 local f = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1588 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1589
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1590 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1591 (This only makes a difference when the body of the function
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1592 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
1593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1594
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1595 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1596 A function definition is an executable expression,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1597 whose value has type <em>function</em>.
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1598 When Luan precompiles a chunk,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1599 all its function bodies are precompiled too.
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1600 Then, whenever Luan executes the function definition,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1601 the function is <em>instantiated</em> (or <em>closed</em>).
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1602 This function instance (or <em>closure</em>)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1603 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
1604
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1605
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1606 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1607 Parameters act as local variables that are
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1608 initialized with the argument values:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1609
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1610 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1611 parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1612 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1613
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1614 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1615 When a function is called,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1616 the list of arguments is adjusted to
1090
616761e0b9f6 update documentation for last change
Franklin Schmidt <fschmidt@gmail.com>
parents: 799
diff changeset
1617 the length of the list of parameters if the list is too short,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1618 unless the function is a <em>vararg function</em>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1619 which is indicated by three dots ('<code>...</code>')
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1620 at the end of its parameter list.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1621 A vararg function does not adjust its argument list;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1622 instead, it collects all extra arguments and supplies them
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1623 to the function through a <em>vararg expression</em>,
371
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1624 which is also written as three dots.
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1625 The value of this expression is a list of all actual extra arguments,
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diff changeset
1626 similar to a function with multiple results.
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1627 If a vararg expression is used inside another expression
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1628 or in the middle of a list of expressions,
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diff changeset
1629 then its return list is adjusted to one element.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1630 If the expression is used as the last element of a list of expressions,
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1631 then no adjustment is made
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1632 (unless that last expression is enclosed in parentheses).
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1633
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1634
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1635 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1636 As an example, consider the following definitions:
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1637
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diff changeset
1638 <pre>
371
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1639 function f(a, b) end
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diff changeset
1640 function g(a, b, ...) end
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1641 function r() return 1,2,3 end
562
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diff changeset
1642 </pre>
417
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diff changeset
1643
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1644 <p>
371
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1645 Then, we have the following mapping from arguments to parameters and
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1646 to the vararg expression:
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1647
562
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diff changeset
1648 <pre>
371
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diff changeset
1649 CALL PARAMETERS
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diff changeset
1650
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diff changeset
1651 f(3) a=3, b=nil
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diff changeset
1652 f(3, 4) a=3, b=4
1090
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parents: 799
diff changeset
1653 f(3, 4, 5) runtime error
616761e0b9f6 update documentation for last change
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parents: 799
diff changeset
1654 f(r(), 10) runtime error
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diff changeset
1655 f(r()) runtime error
371
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diff changeset
1656
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diff changeset
1657 g(3) a=3, b=nil, ... --&gt; (nothing)
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1658 g(3, 4) a=3, b=4, ... --&gt; (nothing)
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diff changeset
1659 g(3, 4, 5, 8) a=3, b=4, ... --&gt; 5 8
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1660 g(5, r()) a=5, b=1, ... --&gt; 2 3
562
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diff changeset
1661 </pre>
371
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1662
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1663 <p>
464
eddf7c73373b fix references in the manual
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diff changeset
1664 Results are returned using the <b>return</b> statement (see <a href="#control">Control Structures</a>).
371
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1665 If control reaches the end of a function
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1666 without encountering a <b>return</b> statement,
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diff changeset
1667 then the function returns with no results.
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diff changeset
1668
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diff changeset
1669
562
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diff changeset
1670 <h4 heading><a name="template_expr">Template Expressions</a></h4>
465
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diff changeset
1671
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diff changeset
1672 <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>
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diff changeset
1673
562
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diff changeset
1674 <pre><%=Html.encode[[
465
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diff changeset
1675 local name = "Bob"
469
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diff changeset
1676 write( %>Hello <%= name %>!<% )
562
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diff changeset
1677 ]]%></pre>
465
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diff changeset
1678
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diff changeset
1679 <p>This is equivalent to the code:</p>
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diff changeset
1680
562
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diff changeset
1681 <pre>
465
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diff changeset
1682 local name = "Bob"
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diff changeset
1683 write( "Hello ", name, "!" )
562
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diff changeset
1684 </pre>
465
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diff changeset
1685
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diff changeset
1686 <p>The strings in template expressions may be multiple lines.</p>
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diff changeset
1687
417
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diff changeset
1688
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1689
562
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diff changeset
1690 <h3 heading><a name="visibility">Visibility Rules</a></h3>
417
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diff changeset
1691
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diff changeset
1692 <p>
a40e99cf0b0b work on manual
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diff changeset
1693 Luan is a lexically scoped language.
371
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1694 The scope of a local variable begins at the first statement after
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diff changeset
1695 its declaration and lasts until the last non-void statement
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diff changeset
1696 of the innermost block that includes the declaration.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1697 Consider the following example:
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diff changeset
1698
562
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diff changeset
1699 <pre>
371
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diff changeset
1700 x = 10 -- global variable
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parents:
diff changeset
1701 do -- new block
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parents:
diff changeset
1702 local x = x -- new 'x', with value 10
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parents:
diff changeset
1703 print(x) --&gt; 10
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parents:
diff changeset
1704 x = x+1
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parents:
diff changeset
1705 do -- another block
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parents:
diff changeset
1706 local x = x+1 -- another 'x'
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parents:
diff changeset
1707 print(x) --&gt; 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1708 end
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parents:
diff changeset
1709 print(x) --&gt; 11
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parents:
diff changeset
1710 end
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diff changeset
1711 print(x) --&gt; 10 (the global one)
562
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diff changeset
1712 </pre>
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parents: 556
diff changeset
1713
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diff changeset
1714 <p>
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diff changeset
1715 Notice that, in a declaration like <code>local x = x</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1716 the new <code>x</code> being declared is not in scope yet,
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diff changeset
1717 and so the second <code>x</code> refers to the outside variable.
371
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parents:
diff changeset
1718
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1719
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1720 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1721 Because of the lexical scoping rules,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1722 local variables can be freely accessed by functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1723 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1724 A local variable used by an inner function is called
562
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diff changeset
1725 an <em>upvalue</em>, or <em>external local variable</em>,
371
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parents:
diff changeset
1726 inside the inner function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1727
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1728
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1729 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1730 Notice that each execution of a <b>local</b> statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1731 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1732 Consider the following example:
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parents:
diff changeset
1733
562
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diff changeset
1734 <pre>
371
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parents:
diff changeset
1735 a = {}
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parents:
diff changeset
1736 local x = 20
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1737 for i=1,10 do
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parents:
diff changeset
1738 local y = 0
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parents:
diff changeset
1739 a[i] = function () y=y+1; return x+y end
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parents:
diff changeset
1740 end
562
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diff changeset
1741 </pre>
417
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diff changeset
1742
a40e99cf0b0b work on manual
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diff changeset
1743 <p>
371
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parents:
diff changeset
1744 The loop creates ten closures
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parents:
diff changeset
1745 (that is, ten instances of the anonymous function).
562
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diff changeset
1746 Each of these closures uses a different <code>y</code> variable,
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diff changeset
1747 while all of them share the same <code>x</code>.
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parents: 556
diff changeset
1748
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parents: 556
diff changeset
1749
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parents: 556
diff changeset
1750
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parents: 556
diff changeset
1751
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diff changeset
1752
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diff changeset
1753 <h2 heading><a name="libs">Standard Libraries</a></h2>
468
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diff changeset
1754
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parents: 465
diff changeset
1755 <p>
9b51e2413cab documentation
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parents: 465
diff changeset
1756 The standard Luan libraries provide useful functions
9b51e2413cab documentation
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parents: 465
diff changeset
1757 that are implemented both in Java and in Luan itself.
9b51e2413cab documentation
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parents: 465
diff changeset
1758 How each function is implemented shouldn't matter to the user.
371
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parents:
diff changeset
1759 Some of these functions provide essential services to the language
562
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diff changeset
1760 (e.g., <a href="#Luan.type"><code>type</code></a> and <a href="#Luan.get_metatable"><code>get_metatable</code></a>);
468
9b51e2413cab documentation
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parents: 465
diff changeset
1761 others provide access to "outside" services (e.g., I/O).
9b51e2413cab documentation
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parents: 465
diff changeset
1762
9b51e2413cab documentation
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parents: 465
diff changeset
1763
562
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diff changeset
1764 <h3 heading><a name="default_lib">Default Environment</a></h3>
468
9b51e2413cab documentation
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parents: 465
diff changeset
1765
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parents: 465
diff changeset
1766 <p>
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parents: 465
diff changeset
1767 These are provided by default as local variables for any Luan code as described in <a href="#env">Environments</a>.
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diff changeset
1768
470
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parents: 469
diff changeset
1769
562
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diff changeset
1770 <h4 heading><a name="require"><code>java ()</code></a></h4>
470
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parents: 469
diff changeset
1771
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parents: 469
diff changeset
1772 <p>
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diff changeset
1773 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.
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diff changeset
1774
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1775
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1776 <h4 heading><a name="require"><code>require (mod_uri)</code></a></h4>
470
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diff changeset
1777
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1778 <p>
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diff changeset
1779 Example use:
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diff changeset
1780
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1781 <pre>
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1782 local Table = require "luan:Table.luan"
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1783 </pre>
470
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diff changeset
1784
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1785 <p>
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1786 Could be defined as:
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diff changeset
1787
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1788 <pre>
470
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diff changeset
1789 local function require(mod_name)
476
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diff changeset
1790 return <a href="#Package.load">Package.load</a>(mod_name) or <a href="#Luan.error">Luan.error</a>("module '"..mod_name.."' not found")
470
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1791 end
562
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1792 </pre>
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diff changeset
1793
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1794
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diff changeset
1795 <h3 heading><a name="luan_lib">Basic Functions</a></h3>
470
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diff changeset
1796
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diff changeset
1797 <p>
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diff changeset
1798 Include this library by:
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1799
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diff changeset
1800 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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1801 local Luan = require "luan:Luan.luan"
562
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1802 </pre>
470
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diff changeset
1803
476
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diff changeset
1804 <p>
470
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diff changeset
1805 The basic library provides basic functions to Luan that don't depend on other libaries.
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1806
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1807
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1808 <h4 heading><a name="Luan.do_file" href="#Luan.do_file"><code>Luan.do_file ([uri])</code></a></h4>
470
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diff changeset
1809
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1810 <p>
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1811 Could be defined as:
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1812
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1813 <pre>
470
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1814 function Luan.do_file(uri)
474
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1815 return <a href="#Luan.load_file">Luan.load_file</a>(uri)()
470
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1816 end
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1817 </pre>
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diff changeset
1818
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diff changeset
1819
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diff changeset
1820
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1821 <h4 heading><a name="Luan.error" href="#Luan.error"><code>Luan.error (message)</code></a></h4>
470
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diff changeset
1822
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1823 <p>
482
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diff changeset
1824 Throws an error containing the message.
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diff changeset
1825
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diff changeset
1826 <p>
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diff changeset
1827 Could be defined as:
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diff changeset
1828
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1829 <pre>
482
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diff changeset
1830 function Luan.error(message)
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diff changeset
1831 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
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1832 end
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1833 </pre>
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diff changeset
1834
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diff changeset
1835
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diff changeset
1836
695
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1837 <h4 heading><a name="Luan.eval" href="#Luan.eval"><code>Luan.eval (text [, source_name])</code></a></h4>
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diff changeset
1838
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diff changeset
1839 <p>
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diff changeset
1840 Evaluates <code>text</code> as a Luan expression.
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diff changeset
1841
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diff changeset
1842 <p>
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diff changeset
1843 Could be defined as:
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diff changeset
1844
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diff changeset
1845 <pre>
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diff changeset
1846 function Luan.eval(text,source_name)
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diff changeset
1847 return Luan.load( "return "..text, source_name or "eval" )()
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1848 end
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diff changeset
1849 </pre>
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diff changeset
1850
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diff changeset
1851
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diff changeset
1852
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diff changeset
1853 <h4 heading><a name="Luan.get_metatable" href="#Luan.get_metatable"><code>Luan.get_metatable (table)</code></a></h4>
562
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diff changeset
1854
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diff changeset
1855 <p>
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diff changeset
1856 If <code>table</code> does not have a metatable, returns <b>nil</b>.
371
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diff changeset
1857 Otherwise,
562
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diff changeset
1858 if the table's metatable has a <code>"__metatable"</code> field,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1859 returns the associated value.
470
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diff changeset
1860 Otherwise, returns the metatable of the given table.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1861
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diff changeset
1862
642
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diff changeset
1863 <h4 heading><a name="Luan.ipairs" href="#Luan.ipairs"><code>Luan.ipairs (t)</code></a></h4>
474
00646edc9d92 documentation
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diff changeset
1864
00646edc9d92 documentation
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diff changeset
1865 <p>
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diff changeset
1866 Returns an iterator function
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1867 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1868
562
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diff changeset
1869 <pre>
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diff changeset
1870 for i,v in ipairs(t) do <em>body</em> end
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diff changeset
1871 </pre>
474
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diff changeset
1872
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diff changeset
1873 <p>
371
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diff changeset
1874 will iterate over the key&ndash;value pairs
562
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diff changeset
1875 (<code>1,t[1]</code>), (<code>2,t[2]</code>), ...,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1876 up to the first nil value.
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parents:
diff changeset
1877
474
00646edc9d92 documentation
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parents: 472
diff changeset
1878 <p>
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diff changeset
1879 Could be defined as:
00646edc9d92 documentation
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diff changeset
1880
562
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diff changeset
1881 <pre>
474
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parents: 472
diff changeset
1882 function Luan.ipairs(t)
00646edc9d92 documentation
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parents: 472
diff changeset
1883 local i = 0
00646edc9d92 documentation
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diff changeset
1884 return function()
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diff changeset
1885 if i < #t then
00646edc9d92 documentation
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diff changeset
1886 i = i + 1
00646edc9d92 documentation
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diff changeset
1887 return i, t[i]
00646edc9d92 documentation
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diff changeset
1888 end
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diff changeset
1889 end
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diff changeset
1890 end
562
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diff changeset
1891 </pre>
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diff changeset
1892
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diff changeset
1893
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diff changeset
1894
695
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diff changeset
1895 <h4 heading><a name="Luan.load" href="#Luan.load"><code>Luan.load (text, source_name [, env])</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1896
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parents:
diff changeset
1897 <p>
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parents:
diff changeset
1898 Loads a chunk.
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parents:
diff changeset
1899
474
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diff changeset
1900 <p>
562
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diff changeset
1901 The <code>text</code> is compiled.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1902 If there are no syntactic errors,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1903 returns the compiled chunk as a function;
474
00646edc9d92 documentation
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diff changeset
1904 otherwise, throws an error.
00646edc9d92 documentation
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diff changeset
1905
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diff changeset
1906 <p>
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diff changeset
1907 The <code>source_name</code> parameter is a string saying where the text came from. It is used to produce error messages.
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diff changeset
1908
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diff changeset
1909 <p>
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diff changeset
1910 If the <code>env</code> parameter is supplied, it becomes the <code>_ENV</code> of the chunk.
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diff changeset
1911
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diff changeset
1912
693
ca169567ce07 module URIs must now include ".luan"
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diff changeset
1913 <h4 heading><a name="Luan.load_file" href="#Luan.load_file"><code>Luan.load_file ([file_uri])</code></a></h4>
562
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diff changeset
1914
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diff changeset
1915 <p>
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diff changeset
1916 Similar to <a href="#Luan.load"><code>load</code></a>,
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diff changeset
1917 but gets the chunk from file <code>file_uri</code>
371
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diff changeset
1918 or from the standard input,
474
00646edc9d92 documentation
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diff changeset
1919 if no file uri is given.
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diff changeset
1920
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diff changeset
1921 <p>
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diff changeset
1922 Could be defined as:
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diff changeset
1923
562
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diff changeset
1924 <pre>
693
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diff changeset
1925 function Luan.load_file(file_uri)
474
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diff changeset
1926 file_uri = file_uri or "stdin:"
693
ca169567ce07 module URIs must now include ".luan"
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diff changeset
1927 local f = Io.uri(file_uri)
474
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parents: 472
diff changeset
1928 f.exists() or <a href="#Luan.error">Luan.error</a>("file '"..file_uri.."' not found")
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diff changeset
1929 return <a href="#Luan.load">Luan.load</a>( f.read_text(), file_uri )
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diff changeset
1930 end
562
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diff changeset
1931 </pre>
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diff changeset
1932
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diff changeset
1933
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diff changeset
1934 <h4 heading><a name="Luan.new_error" href="#Luan.new_error"><code>Luan.new_error (message)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1935
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1936 <p>
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1937 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
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1938
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1939 <p>
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diff changeset
1940 To print the current stack trace, you could do:
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1941
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1942 <pre>
482
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diff changeset
1943 Io.print( Luan.new_error "stack" )
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1944 </pre>
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1945
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1946
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1947 <h4 heading><a name="Luan.pairs" href="#Luan.pairs"><code>Luan.pairs (t)</code></a></h4>
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1948
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1949 <p>
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1950 If <code>t</code> has a metamethod <code>__pairs</code>,
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1951 calls it with <code>t</code> as argument and returns the
475
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1952 result from the call.
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1953
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1954
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1955 <p>
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1956 Otherwise,
475
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1957 returns a function
371
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1958 so that the construction
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1959
562
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1960 <pre>
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1961 for k,v in pairs(t) do <em>body</em> end
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1962 </pre>
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1963
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1964 <p>
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diff changeset
1965 will iterate over all key&ndash;value pairs of table <code>t</code>.
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1966
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1967
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1968
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1969 <h4 heading><a name="Luan.pcall" href="#Luan.pcall"><code>Luan.pcall (f [, arg1, &middot;&middot;&middot;])</code></a></h4>
562
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1970
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1971 <p>
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diff changeset
1972 Calls function <code>f</code> with
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1973 the given arguments in <em>protected mode</em>.
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1974 This means that any error inside&nbsp;<code>f</code> is not propagated;
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1975 instead, <code>pcall</code> catches the error
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1976 and returns a status code.
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1977 Its first result is the status code (a boolean),
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1978 which is true if the call succeeds without errors.
562
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1979 In such case, <code>pcall</code> also returns all results from the call,
371
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1980 after this first result.
562
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1981 In case of any error, <code>pcall</code> returns <b>false</b> plus the error.
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1982
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parents:
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1983
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parents:
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1984
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
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1986 <p>
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parents:
diff changeset
1987 <hr><h3><a name="pdf-print"><code>print (&middot;&middot;&middot;)</code></a></h3>
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1988 Receives any number of arguments
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1989 and prints their values to <code>stdout</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1990 using the <a href="#pdf-tostring"><code>tostring</code></a> function to convert each argument to a string.
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1991 <code>print</code> is not intended for formatted output,
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parents:
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1992 but only as a quick way to show a value,
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parents:
diff changeset
1993 for instance for debugging.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1994 For complete control over the output,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1995 use <a href="#pdf-string.format"><code>string.format</code></a> and <a href="#pdf-io.write"><code>io.write</code></a>.
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1996
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parents:
diff changeset
1997
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parents:
diff changeset
1998
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diff changeset
1999 <h4 heading><a name="Luan.range" href="#Luan.range"><code>Luan.range (start, stop [, step])</code></a></h4>
476
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2000
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diff changeset
2001 <p>
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diff changeset
2002 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
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diff changeset
2003
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diff changeset
2004 <p>
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diff changeset
2005 Example use:
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diff changeset
2006
562
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diff changeset
2007 <pre>
476
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diff changeset
2008 for i in range(1,10) do
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diff changeset
2009 Io.print("count up:",i)
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2010 end
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diff changeset
2011 for i in range(10,0,-1) do
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diff changeset
2012 Io.print("count down:",i)
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diff changeset
2013 end
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diff changeset
2014 </pre>
476
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diff changeset
2015
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diff changeset
2016 <p>
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diff changeset
2017 Could be defined as:
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diff changeset
2018
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diff changeset
2019 <pre>
476
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diff changeset
2020 function Luan.range(start, stop, step)
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diff changeset
2021 step = step or 1
478
eb6d90fb0b5c documentation
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diff changeset
2022 step == 0 and <a href="#Luan.error">Luan.error</a> "bad argument #3 (step may not be zero)"
476
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diff changeset
2023 local i = start
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diff changeset
2024 return function()
cd22e4694ea3 documentation
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diff changeset
2025 if step > 0 and i <= stop or step < 0 and i >= stop then
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diff changeset
2026 local rtn = i
cd22e4694ea3 documentation
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diff changeset
2027 i = i + step
cd22e4694ea3 documentation
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diff changeset
2028 return rtn
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diff changeset
2029 end
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diff changeset
2030 end
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diff changeset
2031 end
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diff changeset
2032 </pre>
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parents: 556
diff changeset
2033
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2034
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2035
642
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diff changeset
2036 <h4 heading><a name="Luan.raw_equal" href="#Luan.raw_equal"><code>Luan.raw_equal (v1, v2)</code></a></h4>
562
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diff changeset
2037
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diff changeset
2038 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2039 Checks whether <code>v1</code> is equal to <code>v2</code>,
371
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parents:
diff changeset
2040 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2041 Returns a boolean.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2043
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2044
642
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diff changeset
2045 <h4 heading><a name="Luan.raw_get" href="#Luan.raw_get"><code>Luan.raw_get (table, index)</code></a></h4>
562
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diff changeset
2046
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2047 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2048 Gets the real value of <code>table[index]</code>,
371
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parents:
diff changeset
2049 without invoking any metamethod.
562
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diff changeset
2050 <code>table</code> must be a table;
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diff changeset
2051 <code>index</code> may be any value.
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diff changeset
2052
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2053
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2054
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diff changeset
2055 <h4 heading><a name="Luan.raw_len" href="#Luan.raw_len"><code>Luan.raw_len (v)</code></a></h4>
562
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diff changeset
2056
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diff changeset
2057 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2058 Returns the length of the object <code>v</code>,
371
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parents:
diff changeset
2059 which must be a table or a string,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2060 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2061 Returns an integer.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2062
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2063
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2064
642
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parents: 629
diff changeset
2065 <h4 heading><a name="Luan.raw_set" href="#Luan.raw_set"><code>Luan.raw_set (table, index, value)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2066
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2067 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2068 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
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parents:
diff changeset
2069 without invoking any metamethod.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2070 <code>table</code> must be a table,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2071 <code>index</code> any value different from <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2072 and <code>value</code> any Lua value.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2073
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2074
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2075 <h4 heading><a name="Luan.set_metatable" href="#Luan.set_metatable"><code>Luan.set_metatable (table, metatable)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2078 Sets the metatable for the given table.
562
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diff changeset
2079 If <code>metatable</code> is <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2080 removes the metatable of the given table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2081 If the original metatable has a <code>"__metatable"</code> field,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2082 raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2083
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2084
1189
73d754b1889f add stringify
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parents: 1164
diff changeset
2085 <h4 heading><a name="Luan.stringify" href="#Luan.stringify"><code>Luan.stringify (v [,strict])</code></a></h4>
73d754b1889f add stringify
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diff changeset
2086
73d754b1889f add stringify
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diff changeset
2087 <p>
73d754b1889f add stringify
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diff changeset
2088 Receives a value of any type and converts it to a string that is a Luan expression. <code>strict</code> is a boolean. If <code>strict</code> is true then invalid types throw an error. If <code>strict</code> is false then invalid types are represented but the resulting expression is invalid. <code>strict</code> defaults to <b>true</b>.
73d754b1889f add stringify
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diff changeset
2089
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parents:
diff changeset
2090
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diff changeset
2091 <h4 heading><a name="Luan.to_string" href="#Luan.to_string"><code>Luan.to_string (v)</code></a></h4>
475
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diff changeset
2092
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diff changeset
2093 <p>
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diff changeset
2094 Receives a value of any type and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2095 converts it to a string in a human-readable format.
475
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diff changeset
2096
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diff changeset
2097 <p>
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diff changeset
2098 If the metatable of <code>v</code> has a <code>"__to_string"</code> field,
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diff changeset
2099 then <code>to_string</code> calls the corresponding value
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diff changeset
2100 with <code>v</code> as argument,
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2101 and uses the result of the call as its result.
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diff changeset
2102
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diff changeset
2103
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diff changeset
2104
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2105 <h4 heading><a name="Luan.try" href="#Luan.try"><code>Luan.try (t, &middot;&middot;&middot;)</code></a></h4>
589
97c8ae330efe add varargs to Luan.try;
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2106
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diff changeset
2107 <p>
97c8ae330efe add varargs to Luan.try;
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diff changeset
2108 Implements try-catch as found in other languages where each block is in table <code>t</code>. <code>t[1]</code> is the "try" block. The <code>t.catch</code> and <code>t.finally</code> blocks are optional. Any extra arguments are passed to the "try" function. Returns the result of the "try" block or the "catch" block.
476
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diff changeset
2109
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diff changeset
2110 <p>
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diff changeset
2111 Example use:
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diff changeset
2112
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diff changeset
2113 <pre>
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diff changeset
2114 try {
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diff changeset
2115 function()
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diff changeset
2116 a_dangerous_fn()
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2117 end
476
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diff changeset
2118 catch = function(e)
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diff changeset
2119 -- handle error
702
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2120 end
476
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diff changeset
2121 finally = function()
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diff changeset
2122 -- clean up
702
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2123 end
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2124 }
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2125 </pre>
476
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diff changeset
2126
482
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diff changeset
2127 <p>
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diff changeset
2128 Could be defined as:
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diff changeset
2129
562
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2130 <pre>
482
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diff changeset
2131 function Luan.try(t)
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parents: 479
diff changeset
2132 local r = { <a href="#Luan.pcall">Luan.pcall</a>(t[1]) }
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parents: 479
diff changeset
2133 if r[1] then
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parents: 479
diff changeset
2134 Table.remove(r,1)
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parents: 479
diff changeset
2135 elseif t.catch ~= nil then
7e9fcfbf22ec documentation
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diff changeset
2136 r = { t.catch(r[2]) }
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diff changeset
2137 else
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diff changeset
2138 t.finally and t.finally()
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diff changeset
2139 r[2].throw()
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diff changeset
2140 end
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diff changeset
2141 t.finally and t.finally()
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diff changeset
2142 return Table.unpack(r)
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diff changeset
2143 end
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2144 </pre>
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diff changeset
2145
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diff changeset
2146
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diff changeset
2147 <h4 heading><a name="Luan.type" href="#Luan.type"><code>Luan.type (v)</code></a></h4>
475
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diff changeset
2148
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diff changeset
2149 <p>
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2150 Returns the type of its only argument, coded as a string.
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2151 The possible results of this function are
562
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2152 "<code>nil</code>" (a string, not the value <b>nil</b>),
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diff changeset
2153 "<code>number</code>",
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diff changeset
2154 "<code>string</code>",
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diff changeset
2155 "<code>binary</code>",
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diff changeset
2156 "<code>boolean</code>",
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diff changeset
2157 "<code>table</code>",
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diff changeset
2158 "<code>function</code>",
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diff changeset
2159 and "<code>java</code>".
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2160
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diff changeset
2161
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diff changeset
2162 <h4 heading><a name="Luan.values" href="#Luan.values"><code>Luan.values (&middot;&middot;&middot;)</code></a></h4>
476
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diff changeset
2163
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diff changeset
2164 <p>
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diff changeset
2165 Returns a function so that the construction
cd22e4694ea3 documentation
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diff changeset
2166
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diff changeset
2167 <pre>
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diff changeset
2168 for v in Luan.values(&middot;&middot;&middot;) do <em>body</em> end
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diff changeset
2169 </pre>
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parents: 556
diff changeset
2170
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diff changeset
2171 <p>
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diff changeset
2172 will iterate over all values of <code>&middot;&middot;&middot;</code>.
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diff changeset
2173
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parents: 556
diff changeset
2174
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parents: 556
diff changeset
2175
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diff changeset
2176 <h4 heading><a name="Luan.VERSION" href="#Luan.VERSION"><code>Luan.VERSION</code></a></h4>
475
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diff changeset
2177
7ac0891718eb documentation
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diff changeset
2178 <p>
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parents:
diff changeset
2179 A global variable (not a function) that
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parents:
diff changeset
2180 holds a string containing the current interpreter version.
562
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diff changeset
2181 The current value of this variable is "<code><%=Luan.VERSION%></code>".
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diff changeset
2182
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parents: 556
diff changeset
2183
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2184
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2185
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parents: 556
diff changeset
2186
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2187
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diff changeset
2188 <h3 heading><a name="package_lib">Modules</a></h3>
476
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parents: 475
diff changeset
2189
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parents: 475
diff changeset
2190 <p>
cd22e4694ea3 documentation
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parents: 475
diff changeset
2191 Include this library by:
cd22e4694ea3 documentation
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parents: 475
diff changeset
2192
562
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diff changeset
2193 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
2194 local Package = require "luan:Package.luan"
562
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diff changeset
2195 </pre>
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parents:
diff changeset
2196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2197 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2198 The package library provides basic
476
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parents: 475
diff changeset
2199 facilities for loading modules in Luan.
cd22e4694ea3 documentation
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parents: 475
diff changeset
2200
cd22e4694ea3 documentation
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parents: 475
diff changeset
2201
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diff changeset
2202 <h4 heading><a name="Package.load" href="#Package.load"><code>Package.load (mod_uri)</code></a></h4>
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diff changeset
2203
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parents:
diff changeset
2204 <p>
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parents:
diff changeset
2205 Loads the given module.
562
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diff changeset
2206 The function starts by looking into the <a href="#Package.loaded"><code>Package.loaded</code></a> table
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diff changeset
2207 to determine whether <code>mod_uri</code> is already loaded.
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diff changeset
2208 If it is, then <code>Package.load</code> returns the value stored
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2209 at <code>Package.loaded[mod_uri]</code>.
476
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diff changeset
2210 Otherwise, it tries to load a new value for the module.
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parents: 475
diff changeset
2211
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diff changeset
2212 <p>
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diff changeset
2213 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.
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diff changeset
2214
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diff changeset
2215 <p>
799
9c13a15a4002 Package.load() now returns false instead of null, and caches the result. This cleans up the luan.isLocked issues.
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parents: 793
diff changeset
2216 Otherwise <code>Package.load</code> tries to read the text of the file referred to by <code>mod_uri</code>. If the file doesn't exist, then <code>Package.load</code> returns <b>false</b>. If the file exists, then its content is compiled into a chunk by calling <a href="#Luan.load"><code>Luan.load</code></a>. This chunk is run passing in <code>mod_uri</code> as an argument. The value returned by the chunk must not be <b>nil</b> and is loaded.
562
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diff changeset
2217
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diff changeset
2218 <p>
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diff changeset
2219 If a new value for the module successful loaded, then it is stored in <code>Package.loaded[mod_uri]</code>. The value is returned.
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diff changeset
2220
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diff changeset
2221
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diff changeset
2222
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diff changeset
2223
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diff changeset
2224 <h4 heading><a name="Package.loaded" href="#Package.loaded"><code>Package.loaded</code></a></h4>
562
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diff changeset
2225
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diff changeset
2226
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diff changeset
2227 <p>
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diff changeset
2228 A table used by <a href="#Package.load"><code>Package.load</code></a> to control which
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diff changeset
2229 modules are already loaded.
562
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diff changeset
2230 When you load a module <code>mod_uri</code> and
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diff changeset
2231 <code>Package.loaded[mod_uri]</code> is not <b>nil</b>,
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diff changeset
2232 <a href="#Package.load"><code>Package.load</code></a> simply returns the value stored there.
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parents:
diff changeset
2233
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2234
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2235 <p>
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parents:
diff changeset
2236 This variable is only a reference to the real table;
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2237 assignments to this variable do not change the
562
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diff changeset
2238 table used by <a href="#Package.load"><code>Package.load</code></a>.
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diff changeset
2239
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parents: 556
diff changeset
2240
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parents: 556
diff changeset
2241
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diff changeset
2242
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diff changeset
2243
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diff changeset
2244
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diff changeset
2245 <h3 heading><a name="string_lib">String Manipulation</a></h3>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2246
e25ba7a2e816 some String documentation and fixes
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diff changeset
2247 <p>
e25ba7a2e816 some String documentation and fixes
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diff changeset
2248 Include this library by:
e25ba7a2e816 some String documentation and fixes
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diff changeset
2249
562
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diff changeset
2250 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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diff changeset
2251 local String = require "luan:String.luan"
562
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diff changeset
2252 </pre>
371
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2253
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diff changeset
2254 <p>
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diff changeset
2255 This library provides generic functions for string manipulation,
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2256 such as finding and extracting substrings, and pattern matching.
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2257 When indexing a string in Luan, the first character is at position&nbsp;1
e25ba7a2e816 some String documentation and fixes
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diff changeset
2258 (not at&nbsp;0, as in Java).
371
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diff changeset
2259 Indices are allowed to be negative and are interpreted as indexing backwards,
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diff changeset
2260 from the end of the string.
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2261 Thus, the last character is at position -1, and so on.
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diff changeset
2262
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2263
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2264
642
c4216a583de4 add links to functions in manual
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diff changeset
2265 <h4 heading><a name="String.char" href="#String.char"><code>String.char (&middot;&middot;&middot;)</code></a></h4>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2266
e25ba7a2e816 some String documentation and fixes
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diff changeset
2267 <p>
371
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diff changeset
2268 Receives zero or more integers.
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diff changeset
2269 Returns a string with length equal to the number of arguments,
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diff changeset
2270 in which each character has the internal numerical code equal
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2271 to its corresponding argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2272
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2273
642
c4216a583de4 add links to functions in manual
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diff changeset
2274 <h4 heading><a name="String.concat" href="#String.concat"><code>String.concat (&middot;&middot;&middot;)</code></a></h4>
562
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diff changeset
2275
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diff changeset
2276 <p>
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diff changeset
2277 Concatenates the <a href="#Luan.to_string"><code>to_string</code></a> value of all arguments.
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diff changeset
2278
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diff changeset
2279
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diff changeset
2280
642
c4216a583de4 add links to functions in manual
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diff changeset
2281 <h4 heading><a name="String.encode" href="#String.encode"><code>String.encode (s)</code></a></h4>
562
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diff changeset
2282
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diff changeset
2283 <p>
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diff changeset
2284 Encodes argument <code>s</code> into a string that can be placed in quotes so as to return the original value of the string.
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diff changeset
2285
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diff changeset
2286
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2287
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2288
642
c4216a583de4 add links to functions in manual
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diff changeset
2289 <h4 heading><a name="String.find" href="#String.find"><code>String.find (s, pattern [, init [, plain]])</code></a></h4>
371
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diff changeset
2290
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parents:
diff changeset
2291 <p>
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diff changeset
2292 Looks for the first match of
562
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diff changeset
2293 <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>.
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diff changeset
2294 If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
371
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diff changeset
2295 where this occurrence starts and ends;
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diff changeset
2296 otherwise, it returns <b>nil</b>.
562
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diff changeset
2297 A third, optional numerical argument <code>init</code> specifies
371
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diff changeset
2298 where to start the search;
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parents:
diff changeset
2299 its default value is&nbsp;1 and can be negative.
562
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diff changeset
2300 A value of <b>true</b> as a fourth, optional argument <code>plain</code>
371
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diff changeset
2301 turns off the pattern matching facilities,
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diff changeset
2302 so the function does a plain "find substring" operation,
562
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diff changeset
2303 with no characters in <code>pattern</code> being considered magic.
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diff changeset
2304 Note that if <code>plain</code> is given, then <code>init</code> must be given as well.
371
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diff changeset
2305
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diff changeset
2306 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2307 If the pattern has captures,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2308 then in a successful match
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parents:
diff changeset
2309 the captured values are also returned,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2310 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2311
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2312
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2313
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2314
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2315 <h4 heading><a name="String.format" href="#String.format"><code>String.format (formatstring, &middot;&middot;&middot;)</code></a></h4>
371
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parents:
diff changeset
2316
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parents:
diff changeset
2317
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2318 <p>
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parents:
diff changeset
2319 Returns a formatted version of its variable number of arguments
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2320 following the description given in its first argument (which must be a string).
562
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diff changeset
2321 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.
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diff changeset
2322
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diff changeset
2323 <p>
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diff changeset
2324 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
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diff changeset
2325
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2326
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2327
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2328 <h4 heading><a name="String.gmatch" href="#String.gmatch"><code>String.gmatch (s, pattern)</code></a></h4>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2329
e25ba7a2e816 some String documentation and fixes
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diff changeset
2330 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2331 Returns an iterator function that,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2332 each time it is called,
562
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diff changeset
2333 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>)
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diff changeset
2334 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2335 If <code>pattern</code> specifies no captures,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2336 then the whole match is produced in each call.
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parents:
diff changeset
2337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2338
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2339 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2340 As an example, the following loop
562
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diff changeset
2341 will iterate over all the words from string <code>s</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2342 printing one per line:
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parents:
diff changeset
2343
562
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diff changeset
2344 <pre>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2345 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes
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diff changeset
2346 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes
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diff changeset
2347 print(w)
e25ba7a2e816 some String documentation and fixes
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diff changeset
2348 end
562
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diff changeset
2349 </pre>
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diff changeset
2350
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diff changeset
2351 <p>
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diff changeset
2352 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
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parents:
diff changeset
2353 given string into a table:
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parents:
diff changeset
2354
562
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diff changeset
2355 <pre>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2356 local t = {}
e25ba7a2e816 some String documentation and fixes
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diff changeset
2357 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes
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diff changeset
2358 for k, v in String.gmatch(s, [[(\w+)=(\w+)]]) do
e25ba7a2e816 some String documentation and fixes
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diff changeset
2359 t[k] = v
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diff changeset
2360 end
562
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diff changeset
2361 </pre>
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diff changeset
2362
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diff changeset
2363 <p>
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diff changeset
2364 For this function, a caret '<code>^</code>' at the start of a pattern does not
371
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parents:
diff changeset
2365 work as an anchor, as this would prevent the iteration.
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parents:
diff changeset
2366
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2367
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2368
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2369 <h4 heading><a name="String.gsub" href="#String.gsub"><code>String.gsub (s, pattern, repl [, n])</code></a></h4>
562
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diff changeset
2370
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diff changeset
2371 <p>
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diff changeset
2372 Returns a copy of <code>s</code>
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diff changeset
2373 in which all (or the first <code>n</code>, if given)
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diff changeset
2374 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
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diff changeset
2375 replaced by a replacement string specified by <code>repl</code>,
371
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diff changeset
2376 which can be a string, a table, or a function.
562
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diff changeset
2377 <code>gsub</code> also returns, as its second value,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2378 the total number of matches that occurred.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2379 The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2380
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2381
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2382 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2383 If <code>repl</code> is a string, then its value is used for replacement.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2384 The character&nbsp;<code>\</code> works as an escape character.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2385 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
2386 with <em>d</em> between 1 and 9,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2387 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
2388 The sequence <code>$0</code> stands for the whole match.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2389
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2390
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2391 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2392 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
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parents:
diff changeset
2393 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
2394
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2395
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2396 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2397 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
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parents:
diff changeset
2398 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
2399 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2400
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2401
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2402 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2403 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2404 if the pattern specifies no captures,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2405 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
2406
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2407
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2408 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2409 If the value returned by the table query or by the function call
555
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2410 is not <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2411 then it is used as the replacement string;
555
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2412 otherwise, if it is <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2413 then there is no replacement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2414 (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
2415
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2417 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2418 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2419
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2420 <pre>
555
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2421 x = String.gsub("hello world", [[(\w+)]], "$1 $1")
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2422 --&gt; x="hello hello world world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2423
555
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2424 x = String.gsub("hello world", [[\w+]], "$0 $0", 1)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2425 --&gt; x="hello hello world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2426
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2427 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
2428 --&gt; x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2429
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2430 x = String.gsub("4+5 = $return 4+5$", [[\$(.*?)\$]], function (s)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2431 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2432 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2433 --&gt; x="4+5 = 9"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2434
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2435 local t = {name="lua", version="5.3"}
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2436 x = String.gsub("$name-$version.tar.gz", [[\$(\w+)]], t)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2437 --&gt; x="lua-5.3.tar.gz"
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2438 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2439
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2440
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2441
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2442 <h4 heading><a name="String.literal" href="#String.literal"><code>String.literal (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2443 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2444 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
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parents: 556
diff changeset
2445
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2446
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2447 <h4 heading><a name="String.lower" href="#String.lower"><code>String.lower (s)</code></a></h4>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2448 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2449 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
2450 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
2451 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
2452
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2453
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2455
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2456 <h4 heading><a name="String.match" href="#String.match"><code>String.match (s, pattern [, init])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2457
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2458 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2459 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2460 <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
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parents: 556
diff changeset
2461 If it finds one, then <code>match</code> returns
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2462 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
2463 otherwise it returns <b>nil</b>.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2464 If <code>pattern</code> specifies no captures,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2465 then the whole match is returned.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2466 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
2467 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
2468 its default value is&nbsp;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
2469
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2470
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2471 <h4 heading><a name="String.matches" href="#String.matches"><code>String.matches (s, pattern)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2472 <p>
629
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2473 Returns a boolean indicating whether the <code>pattern</code> can be found in string <code>s</code>.
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2474 This function is equivalent to
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2475
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2476 <pre>
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2477 return String.match(s,pattern) ~= nil
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2478 </pre>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2479
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2480
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2481 <h4 heading><a name="String.rep" href="#String.rep"><code>String.rep (s, n [, sep])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2482 <p>
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parents: 556
diff changeset
2483 Returns a string that is the concatenation of <code>n</code> copies of
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2484 the string <code>s</code> separated by the string <code>sep</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2485 The default value for <code>sep</code> is the empty string
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2486 (that is, no separator).
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2487 Returns the empty string if <code>n</code> is not positive.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2488
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2489
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2490
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2491
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2492 <h4 heading><a name="String.reverse" href="#String.reverse"><code>String.reverse (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2493 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2494 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
2495
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2496
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2497
1195
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2498 <h4 heading><a name="String.split" href="#String.match"><code>String.split (s, pattern [, limit])</code></a></h4>
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2499
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2500 <p>
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2501 Splits <code>s</code> using regex <code>pattern</code> and returns the results. If <code>limit</code> is positive, then only returns at most that many results. If <code>limit</code> is zero, then remove trailing empty results.
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2502
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2503
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2504
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2505 <h4 heading><a name="String.sub" href="#String.sub"><code>String.sub (s, i [, j])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2506
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2507 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2508 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2509 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
2510 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2511 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
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parents:
diff changeset
2512 (which is the same as the string length).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2513 In particular,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2514 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
2515 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2516 and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2517 with length <code>i</code>.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2518
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2520 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2521 If, after the translation of negative indices,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2522 <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
2523 it is corrected to 1.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2524 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
2525 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
2526 If, after these corrections,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2527 <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
2528 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
2529
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2530
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2531
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2532 <h4 heading><a name="String.to_binary" href="#String.to_binary"><code>String.to_binary (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2533
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2534 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2535 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
2536
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2537
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2538
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2539 <h4 heading><a name="String.to_number" href="#String.to_number"><code>String.to_number (s [, base])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2540
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2541 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2542 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2543 <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
2544 If the argument is
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2545 a string convertible to a number,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2546 then <code>to_number</code> returns this number;
556
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2547 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2548
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2549 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2550
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2551
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2552 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2553 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2554 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
2555 an integer numeral in that base.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2556 In bases above&nbsp;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
2557 represents&nbsp;10, '<code>B</code>' represents&nbsp;11, and so forth,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2558 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2559 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
2560 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2561
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2562
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2563
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2564 <h4 heading><a name="String.trim" href="#String.trim"><code>String.trim (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2565
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2566 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2567 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
2568
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2569
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2572 <h4 heading><a name="String.unicode" href="#String.unicode"><code>String.unicode (s [, i [, j]])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2573
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2574 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2575 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
2576 <code>s[i+1]</code>, ..., <code>s[j]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2577 The default value for <code>i</code> is&nbsp;1;
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2578 the default value for <code>j</code> is&nbsp;<code>i</code>.
556
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2579 These indices are corrected
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2580 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
2581
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2582
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2583
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2584
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2585
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2586 <h4 heading><a name="String.upper" href="#String.upper"><code>String.upper (s)</code></a></h4>
556
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2587 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2588 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
2589 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
2590 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
2591 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
2592
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2596
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2597 <h3 heading><a name="binary_lib">Binary Manipulation</a></h3>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2598
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2599 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2600 Include this library by:
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2601
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2602 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2603 local Binary = require "luan:Binary.luan"
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2604 </pre>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2605
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2606
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2607 <h4 heading><a name="Binary.binary" href="#Binary.binary"><code>Binary.binary (&middot;&middot;&middot;)</code></a></h4>
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2608
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2609 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2610 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2611 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2612 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2613 to its corresponding argument.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2614
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2615
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2616 <h4 heading><a name="Binary.byte" href="#Binary.byte"><code>Binary.byte (b [, i [, j]])</code></a></h4>
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2617
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2618 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2619 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2620 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2621 The default value for <code>i</code> is&nbsp;1;
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2622 the default value for <code>j</code> is&nbsp;<code>i</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2623 These indices are corrected
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2624 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
2625
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2626
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2627 <h4 heading><a name="Binary.to_string" href="#Binary.to_string"><code>Binary.to_string (b)</code></a></h4>
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2628 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2629 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
2630
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2631
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2632
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2633
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2634 <h3 heading><a name="table_lib">Table Manipulation</a></h3>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2635
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2636 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2637 Include this library by:
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2638
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2639 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2640 local Table = require "luan:Table.luan"
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2641 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2642
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2643 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2644 This library provides generic functions for table manipulation.
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2645 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2646
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2647
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2648
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2649 <h4 heading><a name="Table.clear" href="#Table.clear"><code>Table.clear (tbl)</code></a></h4>
580
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2650
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2651 <p>
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2652 Clears the table.
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2653
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2654
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2655 <h4 heading><a name="Table.concat" href="#Table.concat"><code>Table.concat (list [, sep [, i [, j]]])</code></a></h4>
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2656
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2657 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2658 Given a list,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2659 returns the string <code>list[i]..sep..list[i+1] &middot;&middot;&middot; sep..list[j]</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2660 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
2661 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
2662 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
2663 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
2664
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2665
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2666 <h4 heading><a name="Table.copy" href="#Table.copy"><code>Table.copy (tbl [, i [, j]])</code></a></h4>
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2667
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2668 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2669 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
2670 Otherwise returns a new table which is a list of the elements <code>tbl[i] &middot;&middot;&middot; tbl[j]</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2671 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2672
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2673
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2674
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2675 <h4 heading><a name="Table.insert" href="#Table.insert"><code>Table.insert (list, pos, value)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2676
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2677 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2678 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
2679 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2680 <code>list[pos], list[pos+1], &middot;&middot;&middot;, list[#list]</code>.
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2681
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2682
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2683
1100
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2684 <h4 heading><a name="Table.is_empty" href="#Table.is_empty"><code>Table.is_empty (tbl)</code></a></h4>
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2685
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2686
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2687
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2688 <h4 heading><a name="Table.pack" href="#Table.pack"><code>Table.pack (&middot;&middot;&middot;)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2690 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2691 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
2692 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
2693 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
2694
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2698 <h4 heading><a name="Table.remove" href="#Table.remove"><code>Table.remove (list, pos)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2699
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2700
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2701 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2702 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
2703 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
2704 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
2705 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
2706 <code>list[pos+1], list[pos+2], &middot;&middot;&middot;, list[#list]</code>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2707 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
2708 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
2709 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
2710 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
2711
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2712
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2713
1100
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2714 <h4 heading><a name="Table.size" href="#Table.size"><code>Table.size (tbl)</code></a></h4>
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2715
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2716
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2717
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2718 <h4 heading><a name="Table.sort" href="#Table.sort"><code>Table.sort (list [, comp])</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2719
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2720 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2721 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
2722 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
2723 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
2724 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
2725 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
2726 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
2727 (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
2728 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
2729 then the standard Lua operator <code>&lt;</code> is used instead.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2730
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2731 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2732 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
2733 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
2734 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
2735
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2736
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2737
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2738 <h4 heading><a name="Table.unpack" href="#Table.unpack"><code>Table.unpack (list [, i [, j]])</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2739
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2740 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2741 Returns the 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
2742 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
2743
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2744 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2745 return list[i], list[i+1], &middot;&middot;&middot;, list[j]
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2746 </pre>
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 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2749 By default, <code>i</code> is&nbsp;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
2750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2751
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2752
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2753
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2754 <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
2755
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2756 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2757 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2758
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2759 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2760 local Number = require "luan:Number.luan"
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2761 </pre>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2762
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2763
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2764 <h4 heading><a name="Number.double" href="#Number.double"><code>Number.double (x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2765 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2766 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2767
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2768
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2769 <h4 heading><a name="Number.integer" href="#Number.integer"><code>Number.integer (x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2770 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2771 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
2772 returns that integer.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2773 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2774
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2775
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2776 <h4 heading><a name="Number.long" href="#Number.long"><code>Number.long (x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2777 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2778 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
2779 returns that long.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2780 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2781
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2782
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2783 <h4 heading><a name="Number.long_to_string" href="#Number.long_to_string"><code>Number.long_to_string (i, radix)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2784 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2785 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
2786
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2787
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2788 <h4 heading><a name="Number.type" href="#Number.type"><code>Number.type (x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2789 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2790 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
2791
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2792
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2793
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2794
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2795 <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
2796
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2797 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2798 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2799
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2800 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2801 local Math = require "luan:Math.luan"
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2802 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2804 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2805 This library provides basic mathematical functions.
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2806 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
2807
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2808
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2809 <h4 heading><a name="Math.abs" href="#Math.abs"><code>Math.abs (x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2810
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2811 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2812 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
2813
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2814
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2815
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2816 <h4 heading><a name="Math.acos" href="#Math.acos"><code>Math.acos (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2817
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2818 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2819 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
2820
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2821
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2822
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2823
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2824 <h4 heading><a name="Math.asin" href="#Math.asin"><code>Math.asin (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2825
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2826 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2827 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
2828
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2829
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2830
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2831
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2832 <h4 heading><a name="Math.atan" href="#Math.atan"><code>Math.atan (y, x)</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2833
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2834 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2835 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
2836 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
2837 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2838 (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
2839
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2840
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2841
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2842
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2843 <h4 heading><a name="Math.ceil" href="#Math.ceil"><code>Math.ceil (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2844
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2845 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2846 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
2847
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2848
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2849
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2850
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2851 <h4 heading><a name="Math.cos" href="#Math.cos"><code>Math.cos (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2852
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2853 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2854 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
2855
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2856
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2857
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2858
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2859 <h4 heading><a name="Math.deg" href="#Math.deg"><code>Math.deg (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
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 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
2863
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2864
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2865
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2866
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2867 <h4 heading><a name="Math.exp" href="#Math.exp"><code>Math.exp (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2868
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2869 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2870 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
2871 (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
2872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2873
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2874
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2875
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2876 <h4 heading><a name="Math.floor" href="#Math.floor"><code>Math.floor (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2877
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2878 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2879 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
2880
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2881
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2882
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2883
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2884 <h4 heading><a name="Math.fmod" href="#Math.fmod"><code>Math.fmod (x, y)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2885
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2886 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2887 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
2888 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2889
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
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2892
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2893 <h4 heading><a name="Math.huge" href="#Math.huge"><code>Math.huge</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2894
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2895 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2896 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
2897
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2901 <h4 heading><a name="Math.log" href="#Math.log"><code>Math.log (x [, base])</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2902
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2903 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2904 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
2905 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
2906 (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
2907
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2908
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2909
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2910
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2911 <h4 heading><a name="Math.max" href="#Math.max"><code>Math.max (x, &middot;&middot;&middot;)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2913 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2914 Returns the argument with the maximum value,
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2915 according to the Lua operator <code>&lt;</code>.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2916
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2917
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2918
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2919
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2920 <h4 heading><a name="Math.max_integer" href="#Math.max_integer"><code>Math.max_integer</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2921 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2922 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
2923
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2924
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2925
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2926
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2927 <h4 heading><a name="Math.min" href="#Math.min"><code>Math.min (x, &middot;&middot;&middot;)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2928
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2929 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2930 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
2931 according to the Lua operator <code>&lt;</code>.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2932
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2933
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2934
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2935
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2936 <h4 heading><a name="Math.min_integer" href="#Math.min_integer"><code>Math.min_integer</code></a></h4>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2937 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2938 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
2939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2942
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2943 <h4 heading><a name="Math.modf" href="#Math.modf"><code>Math.modf (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2944
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2945 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2946 Returns the 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
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2951 <h4 heading><a name="Math.pi" href="#Math.pi"><code>Math.pi</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2953 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2954 The value of <em>&pi;</em>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2955
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2956
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2957
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2958
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2959 <h4 heading><a name="Math.rad" href="#Math.rad"><code>Math.rad (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2960
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2961 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2962 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
2963
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2964
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2965
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2966
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2967 <h4 heading><a name="Math.random" href="#Math.random"><code>Math.random ([m [, n])</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2970 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2971 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2972 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
2973 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
2974 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
2975 <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
2976 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
2977 (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
2978 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
2979
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2980
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2981 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2982 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
2983 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
2984 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
2985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2986
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2987
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2988
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2989 <h4 heading><a name="Math.sin" href="#Math.sin"><code>Math.sin (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2990
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2991 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2992 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
2993
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2994
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2996
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2997 <h4 heading><a name="Math.sqrt" href="#Math.sqrt"><code>Math.sqrt (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2998
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2999 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3000 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
3001 (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
3002
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3003
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3004
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3005
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3006 <h4 heading><a name="Math.tan" href="#Math.tan"><code>Math.tan (x)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3007
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3008 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3009 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
3010
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3011
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3013
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3016
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3017
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3018 <h2>6.8 &ndash; <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
3019
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3020 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3021 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
3022 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
3023 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
3024 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3025 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
3026 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
3027
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3029 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3030 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
3031 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
3032 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
3033 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
3034 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
3035
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3038 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
3039 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
3040 <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
3041 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3045 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3046 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
3047 (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
3048 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
3049 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
3050 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3051 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
3052 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3053 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
3054 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
3055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3056
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3057 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3058 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3062 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
3063 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
3064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3065
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3066
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3069 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3073 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
3074
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3075
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3076
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3077
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3078 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3079 <hr><h3><a name="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
3080
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3081
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3082 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3083 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
3084 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
3085 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
3086 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
3087 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3088 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
3089
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3090
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3091 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3092 In case of errors 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
3093 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
3094
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3095
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3096
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3097
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3098 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3099 <hr><h3><a name="pdf-io.lines"><code>io.lines ([filename &middot;&middot;&middot;])</code></a></h3>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3100
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3101
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3102 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3103 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
3104 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
3105 works like <code>file:lines(&middot;&middot;&middot;)</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
3106 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
3107 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
3108
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3109
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3110 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3111 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
3112 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
3113 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
3114 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
3115
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3116
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3117 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3118 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
3119 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
3120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3123
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3124 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3125 <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
3126
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3129 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
3130 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
3131 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
3132 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
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 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
3137
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3138 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3139 <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
3140 <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
3141 <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
3142 <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
3143 <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
3144 <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
3145 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
3146 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3147 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
3148 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
3149
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3150
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3151
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3152
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3153 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3154 <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
3155
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3157 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3158 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
3159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3160
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3161
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3162
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3163 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3164 <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
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 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
3169 on all platforms.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3170
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3172 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3173 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
3174 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
3175 (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
3176 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
3177 (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
3178
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3179
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3180
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3182 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3183 <hr><h3><a name="pdf-io.read"><code>io.read (&middot;&middot;&middot;)</code></a></h3>
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3186 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3187 Equivalent to <code>io.input():read(&middot;&middot;&middot;)</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3188
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3190
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3191
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3192 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3193 <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
3194
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3195
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3196 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3197 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
3198 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
3199 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
3200
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3201
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3202
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3203
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3204 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3205 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3209 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
3210 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
3211 <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
3212 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
3213
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3214
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3215
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3217 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3218 <hr><h3><a name="pdf-io.write"><code>io.write (&middot;&middot;&middot;)</code></a></h3>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3220
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3221 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3222 Equivalent to <code>io.output():write(&middot;&middot;&middot;)</code>.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3226
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3227 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3228 <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
3229
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3230
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3231 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3232 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3233 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
3234 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
3235 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3239 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
3240 <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
3241 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
3242
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3244
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3247 <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
3248
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3249
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3250 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3251 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
3252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3253
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3254
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3255
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3256 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3257 <hr><h3><a name="pdf-file:lines"><code>file:lines (&middot;&middot;&middot;)</code></a></h3>
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3261 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
3262 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
3263 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
3264 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
3265 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
3266 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
3267
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3268 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3269 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
3270 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3271 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
3272 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
3273 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
3274 when the loop ends.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3275
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3276
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3277 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3278 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
3279 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
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:read"><code>file:read (&middot;&middot;&middot;)</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 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
3290 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
3291 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3292 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
3293 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
3294 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3295 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
3296 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3297 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
3298 (see below).
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3302 The available formats are
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3303
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3304 <ul>
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 <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
3307 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
3308 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
3309 (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
3310 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
3311 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
3312 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
3313 (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
3314 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
3315 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3317 <li><b>"<code>i</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3318 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
3319 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3321 <li><b>"<code>a</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3322 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
3323 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
3324 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3325
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3326 <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
3327 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
3328 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
3329 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
3330 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3331
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3332 <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
3333 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
3334 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
3335 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3336
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3337 <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
3338 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
3339 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
3340 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
3341 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
3342 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
3343 </li>
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 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3346 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
3347
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3348
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3351 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3352 <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
3353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3354
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3355 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3356 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
3357 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
3358 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
3359 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
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 <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
3363 <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
3364 <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
3365 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3366 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
3367 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
3368 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
3369 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
3370
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3372 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3373 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
3374 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
3375 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
3376 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
3377 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
3378 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
3379 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
3380 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
3381
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3384
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3385 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3386 <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
3387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3388
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3389 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3390 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
3391 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
3392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3393 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3394
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3395 <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
3396 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
3397 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3398
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3399 <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
3400 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
3401 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
3402 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
3403 </li>
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 <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
3406 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
3407 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
3408 (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
3409 </li>
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 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3412 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
3413 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
3414 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
3415
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3417
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3418
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3419 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3420 <hr><h3><a name="pdf-file:write"><code>file:write (&middot;&middot;&middot;)</code></a></h3>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3421
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3422
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3423 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3424 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
3425 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
3426
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3427
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3428 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3429 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
3430 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
3431
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3432
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3433
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3434
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3435
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3436
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3437
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3438 <h2>6.9 &ndash; <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
3439
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3440 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3441 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
3442
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3443
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3444 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3445 <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
3446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3448 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3449 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
3450 used by the program.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3453
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3455 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3456 <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
3457
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3458
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3459 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3460 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
3461 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
3462
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3463
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3464 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3465 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
3466 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
3467 (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
3468 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
3469
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3470
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3471 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3472 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
3473 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
3474 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3475 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
3476 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
3477 <code>year</code> (four digits), <code>month</code> (1&ndash;12), <code>day</code> (1&ndash;31),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3478 <code>hour</code> (0&ndash;23), <code>min</code> (0&ndash;59), <code>sec</code> (0&ndash;61),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3479 <code>wday</code> (weekday, Sunday is&nbsp;1),
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3480 <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
3481 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
3482 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
3483 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
3484
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3485
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3486 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3487 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
3488 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
3489 formatted according to the same rules as the ISO&nbsp;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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3493 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3494 <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
3495 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
3496 (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
3497
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3499 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3500 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3501 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
3502 because of its reliance on C&nbsp;function <code>gmtime</code> and C&nbsp;function <code>localtime</code>.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3507 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3508 <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
3509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3511 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3512 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
3513 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
3514 (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
3515 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
3516 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
3517
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3518
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3519
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 <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
3523
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3525 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3526 This function is equivalent to the ISO&nbsp;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
3527 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
3528 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
3529 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
3530 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
3531 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3532 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
3533 as follows:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3534
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3535 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3536
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3537 <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
3538 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3539 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
3540 </li>
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 <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
3543 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
3544 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
3545 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3546
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3547 </ul>
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 a <code>command</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3551 <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
3552
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3553
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 <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
3558
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3559
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3560 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3561 Calls the ISO&nbsp;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
3562 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
3563 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
3564 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
3565 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
3566 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
3567 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
3568 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
3569
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3570
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3571 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3572 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
3573 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
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.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
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 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
3584 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
3585
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3586
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3587
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3588
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3589 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3590 <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
3591
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3592
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3593 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3594 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
3595 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3596 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
3597 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
3598
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3599
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3600
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3601
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3602 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3603 <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
3604
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 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
3608 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
3609 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3614 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3615 <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
3616
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3617
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3618 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3619 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
3620 <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
3621 <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
3622 <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
3623 <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
3624 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
3625 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
3626 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
3627
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3628
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3629 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3630 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
3631 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
3632 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
3633 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
3634
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3635
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3636 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3637 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
3638 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
3639 for the given category.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3640
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3641
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3642 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3643 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
3644 because of its reliance on C&nbsp;function <code>setlocale</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3645
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3646
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3647
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3650 <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
3651
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3652
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3653 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3654 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
3655 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
3656 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
3657 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3658 <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
3659 <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
3660 <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
3661 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
3662 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
3663
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3664
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3665 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3666 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
3667 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
3668 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
3669 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
3670 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
3671 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
3672 <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
3673
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3674
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3675
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3676
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3677 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3678 <hr><h3><a name="pdf-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
3679
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3680
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3681 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3682 Returns 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
3683 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
3684 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
3685 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
3686
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3688 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3689 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3690 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
3691 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3692 (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
3693 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
3694 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
3695 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
3696
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3699 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3700 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
3701 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3707
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3708
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3709 <h2>6.10 &ndash; <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
3710
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3711 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3712 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3713 the functionality of the debug interface (<a href="#4.9">&sect;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
3714 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
3715 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3716 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
3717 (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
3718 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
3719 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
3720 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
3721 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
3722 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
3723
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3724
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3725 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3726 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
3727 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
3728 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
3729 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
3730 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3731 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
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-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
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 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
3740 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
3741 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
3742 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
3743 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
3744 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
3745 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
3746
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3747
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3748 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3749 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
3750 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
3751
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3752
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 <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
3757
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3758
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3759 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3760 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
3761 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
3762 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
3763 (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
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
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 <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
3770
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3771
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3772 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3773 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
3774 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
3775 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
3776 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
3777 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3778 level&nbsp;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
3779 level&nbsp;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
3780 (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
3781 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3782 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
3783 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
3784
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3785
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3786 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3787 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
3788 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
3789 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
3790 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
3791 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3792 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
3793 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
3794 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3795 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
3796 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
3797 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3798
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3799
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3800 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3801 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
3802 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
3803 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
3804 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
3805 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
3806 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
3807
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3809
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3810
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3811 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3812 <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
3813
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3816 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
3817 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
3818 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
3819 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
3820
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3821
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3822 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3823 The first parameter or local variable has index&nbsp;1, and so on,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3824 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
3825 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
3826 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
3827 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
3828 -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
3829 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
3830 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
3831 (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
3832
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3833
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3834 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3835 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
3836 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
3837 (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
3838 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
3839
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3840
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3841 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3842 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
3843 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
3844
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3845
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3846
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3847
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3848 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3849 <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
3850
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3851
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3852 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3853 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
3854 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
3855
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3856
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3857
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3858
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3859 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3860 <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
3861
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3862
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3863 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3864 Returns the registry table (see <a href="#4.5">&sect;4.5</a>).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3865
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3866
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3867
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3868
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3869 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3870 <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
3871
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3873 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3874 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
3875 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
3876 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
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 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
3881 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
3882 (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
3883
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3884
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3885
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3886
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3887 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3888 <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
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 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
3893 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
3894 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3895
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3896
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3897
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3898
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3899 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3900 <hr><h3><a name="pdf-debug.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
3901
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3902
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3903 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3904 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
3905 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
3906 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
3907 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
3908 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3909
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3910 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3911 <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
3912 <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
3913 <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
3914 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3915 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3916 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
3917 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
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 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3922 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3926 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
3927 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
3928 <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
3929 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3930 <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
3931 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3932 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
3933 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3934 you can call <code>getinfo</code> with level&nbsp;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
3935 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3936 (level&nbsp;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
3937 and level&nbsp;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
3938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3942 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3943 <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
3944
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3945
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3946 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3947 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
3948 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
3949 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
3950 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
3951 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
3952 (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
3953 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
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 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
3958 variable indices and names.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3961
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3962
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3963 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3964 <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
3965
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3966
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3967 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3968 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
3969 (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
3970 Returns <code>value</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3971
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3972
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3973
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3974
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3975 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3976 <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
3977
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3978
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3979 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3980 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
3981 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
3982 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
3983 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3984 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
3985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3986
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3987
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3988
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3989 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3990 <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
3991
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3992
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3993 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3994 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
3995 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
3996 <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
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 Returns <code>udata</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4001
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4002
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4003
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4004
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4005 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4006 <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
4007
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4008
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4009 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4010 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
4011 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
4012 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4013 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
4014 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
4015 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
4016 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
4017 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4018 (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
4019
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4020
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4021
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4023 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4024 <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
4025
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4026
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4027 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4028 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
4029 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
4030 from the given function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4031
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4032
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4033 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4034 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
4035 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4036 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
4037 (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
4038 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
4039
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4040
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4041
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4043 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4044 <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
4045
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4046
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4047 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4048 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
4049 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
4050
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4051
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4052
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4053
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4057 <h1>7 &ndash; <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
4058
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4059 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4060 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
4061 to be embedded in a host C&nbsp;program,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4062 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
4063 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
4064 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
4065 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
4066 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4067 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
4068 Its usage is:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4069
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4070 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4071 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4072 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4073 The options are:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4074
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4075 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4076 <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
4077 <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
4078 <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
4079 <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
4080 <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
4081 <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
4082 <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
4083 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4084 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
4085 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4086 <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
4087 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
4088 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
4089
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4090
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4091 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4092 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
4093 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
4094 (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
4095 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4096 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
4097 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
4098 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
4099
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4100
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4101 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4102 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
4103 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
4104 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4105 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
4106 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4107 <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
4108 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4112 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
4113 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
4114
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4115 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4116 $ 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
4117 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4118 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
4119 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
4120 (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
4121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4123 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4124 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4125 <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
4126 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
4127 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
4128 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
4129 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4130 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
4131 (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
4132 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4133 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
4134
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4135 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4136 $ 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
4137 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4138 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
4139
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4140 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4141 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
4142 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4143 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4144 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4145 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
4146 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
4147 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
4148 For instance, the call
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4149
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4150 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4151 $ 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
4152 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4153 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
4154 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
4155 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
4156 <code>arg[1]</code>, &middot;&middot;&middot;, <code>arg[#arg]</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4157 (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
4158 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
4159
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4160
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4161 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4162 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4163 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
4164 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4165 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
4166 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
4167 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
4168 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
4169 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
4170 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
4171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4172
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4173 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4174 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
4175 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
4176 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
4177 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
4178 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
4179 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
4180 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
4181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4182
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4183 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4184 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4185 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
4186 (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
4187 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
4188 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
4189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4190
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4191 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4192 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
4193 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
4194 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4195 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
4196 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
4197 by using <code>chmod +x</code> and the&nbsp;<code>#!</code> form,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4198 as in
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4200 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4201 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4202 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4203 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4204 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
4205 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
4206 then
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4207
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4208 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4209 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4210 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4211 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
4212
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4213
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4214
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4215 <h1>8 &ndash; <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
4216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4217 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4218 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
4219 from Lua&nbsp;5.2 to Lua&nbsp;5.3.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4220 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
4221 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
4222 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4223 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
4224
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4226 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4227 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
4228 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
4229 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
4230 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
4231 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4232 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
4233 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4234 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
4235 using a new version.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4236
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4237
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4238 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4239 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
4240 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4241 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
4242
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4244 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4245 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
4246 change between versions.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4249
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4250 <h2>8.1 &ndash; <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
4251 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4253 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4254 The main difference between Lua&nbsp;5.2 and Lua&nbsp;5.3 is the
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4255 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
4256 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
4257 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4258 (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
4259 can give different results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4260
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4261
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4262 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4263 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
4264 (in Lua&nbsp;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
4265 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
4266 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
4267 (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
4268 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4269 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
4270 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4271 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
4272 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
4273 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4274
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4275 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4276 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
4277 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
4278 (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
4279 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
4280 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
4281 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
4282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4285 (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
4286 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
4287 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
4288 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4289
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4290 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4291 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
4292 (It was an experimental feature in Lua&nbsp;5.2.)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4293 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4294
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4295 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4296
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4297
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4298
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 <h2>8.2 &ndash; <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
4301 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4302
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4303 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4304 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
4305 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
4306 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
4307 (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
4308 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
4309 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4310
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4311 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4312 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
4313 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
4314 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4316 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4317 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
4318 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
4319 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4321 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4322 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
4323 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
4324 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4325
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4326 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4327 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
4328 <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
4329 <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
4330 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
4331 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
4332 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
4333 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
4334 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4335 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
4336 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4337 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4338
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4339 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4340 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
4341 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
4342 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
4343 (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
4344 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
4345 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
4346 (Lua&nbsp;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
4347 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
4348 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4350 </ul>
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
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 <h2>8.3 &ndash; <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
4356
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4357
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4358 <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 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
4362 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
4363 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
4364 Adapt your code accordingly.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4365 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4366
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4367 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4368 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
4369 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
4370 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4372 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4373 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
4374 (<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
4375 <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
4376 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4377 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
4378 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4379
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4380 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4381 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
4382 (<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
4383 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4384 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
4385 (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
4386 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4388 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4389
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4390
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4391
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4393 <h1>9 &ndash; <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
4394
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4395 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4396 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
4397 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
4398 {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
4399 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
4400 (For operator precedences, see <a href="#3.4.8">&sect;3.4.8</a>;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4401 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
4402 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4403 and LiteralString, see <a href="#3.1">&sect;3.1</a>.)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4404
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4405
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4406
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4407
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4408 <pre>
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 chunk ::= block
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 block ::= {stat} [retstat]
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 stat ::= &lsquo;<b>;</b>&rsquo; |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4415 varlist &lsquo;<b>=</b>&rsquo; explist |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4416 functioncall |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4417 label |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4418 <b>break</b> |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4419 <b>goto</b> Name |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4420 <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
4421 <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
4422 <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
4423 <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
4424 <b>for</b> Name &lsquo;<b>=</b>&rsquo; exp &lsquo;<b>,</b>&rsquo; exp [&lsquo;<b>,</b>&rsquo; 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
4425 <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
4426 <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
4427 <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
4428 <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4429
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4430 retstat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4431
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4432 label ::= &lsquo;<b>::</b>&rsquo; Name &lsquo;<b>::</b>&rsquo;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4433
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4434 funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4435
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4436 varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4437
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4438 var ::= Name | prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; | prefixexp &lsquo;<b>.</b>&rsquo; Name
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4439
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4440 namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4441
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4442 explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4443
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4444 exp ::= <b>nil</b> | <b>false</b> | <b>true</b> | Numeral | LiteralString | &lsquo;<b>...</b>&rsquo; | functiondef |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4445 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
4446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4447 prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
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 functioncall ::= prefixexp args | prefixexp &lsquo;<b>:</b>&rsquo; Name args
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4450
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4451 args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo; | tableconstructor | LiteralString
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4452
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4453 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
4454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4455 funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4456
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4457 parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4458
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4459 tableconstructor ::= &lsquo;<b>{</b>&rsquo; [fieldlist] &lsquo;<b>}</b>&rsquo;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4460
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4461 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
4462
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4463 field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
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 fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo;
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 binop ::= &lsquo;<b>+</b>&rsquo; | &lsquo;<b>-</b>&rsquo; | &lsquo;<b>*</b>&rsquo; | &lsquo;<b>/</b>&rsquo; | &lsquo;<b>//</b>&rsquo; | &lsquo;<b>^</b>&rsquo; | &lsquo;<b>%</b>&rsquo; |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4468 &lsquo;<b>&amp;</b>&rsquo; | &lsquo;<b>~</b>&rsquo; | &lsquo;<b>|</b>&rsquo; | &lsquo;<b>&gt;&gt;</b>&rsquo; | &lsquo;<b>&lt;&lt;</b>&rsquo; | &lsquo;<b>..</b>&rsquo; |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4469 &lsquo;<b>&lt;</b>&rsquo; | &lsquo;<b>&lt;=</b>&rsquo; | &lsquo;<b>&gt;</b>&rsquo; | &lsquo;<b>&gt;=</b>&rsquo; | &lsquo;<b>==</b>&rsquo; | &lsquo;<b>~=</b>&rsquo; |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4470 <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
4471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4472 unop ::= &lsquo;<b>-</b>&rsquo; | <b>not</b> | &lsquo;<b>#</b>&rsquo; | &lsquo;<b>~</b>&rsquo;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4473
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4474 </pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4476 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4477
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4479
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4482
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4483
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4484
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4485 <HR>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4486 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4487 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4488 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
4489 </SMALL>
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 Last change: minor edit
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
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4494 </div>
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2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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4496 </body>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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4497 </html>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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4498 <%
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4499 end