annotate website/src/manual.html @ 1387:bc40bc9aab3a

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date Mon, 02 Sep 2019 22:23:12 -0600
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1 <!doctype html>
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2 <html>
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3 <head>
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4 <title>Luan Reference Manual</title>
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5 <style>
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6 @import "site.css";
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7 </style>
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8 </head>
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9 <body>
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10
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11 <div small>
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12 <a href=".">Luan</a>
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13 / <a href="docs.html">Documentation</a>
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14 </div>
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15
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16 <h1><a href="manual.html">Luan Reference Manual</a></h1>
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17
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18 <p small>
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19 Original copyright &copy; 2015 Lua.org, PUC-Rio.
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20 Freely available under the terms of the
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21 <a href="http://www.lua.org/license.html">Lua license</a>.
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22 Modified for Luan.
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23 </p>
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24
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25 <hr/>
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26
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27 <h2>Contents</h2>
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28
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29 <div contents><a href="#intro">Introduction</a></div>
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30
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31 <div contents>
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32 <a href="#basic">Basic Concepts</a>
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33 <ul>
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34 <li><a href="#types">Values and Types</a></li>
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35 <li><a href="#env">Environments</a></li>
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36 <li><a href="#error">Error Handling</a></li>
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37 <li><a href="#meta">Metatables and Metamethods</a></li>
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38 <li><a href="#gc">Garbage Collection</a></li>
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39 </ul>
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40 </div>
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41
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42 <div contents>
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43 <a href="#lang">The Language</a>
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44 <ul>
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45 <li><a href="#lex">Lexical Conventions</a></li>
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46 <li><a href="#vars">Variables</a></li>
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47 <li>
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48 <a href="#stmts">Statements</a>
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49 <ul>
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50 <li><a href="#blocks">Blocks</a></li>
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51 <li><a href="#chunks">Chunks</a></li>
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52 <li><a href="#assignment">Assignment</a></li>
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53 <li><a href="#control">Control Structures</a></li>
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54 <li><a href="#for">For Statement</a></li>
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55 <li><a href="#fn_stmt">Function Calls as Statements</a></li>
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56 <li><a href="#local_stmt">Local Declarations</a></li>
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57 <li><a href="#template_stmt">Template Statements</a></li>
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58 </ul>
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59 </li>
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60 <li>
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61 <a href="#expressions">Expressions</a>
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62 <ul>
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63 <li><a href="#arithmetic">Arithmetic Operators</a></li>
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64 <li><a href="#conversions">Coercions and Conversions</a></li>
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65 <li><a href="#relational">Relational Operators</a></li>
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66 <li><a href="#logical_ops">Logical Operators</a></li>
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67 <li><a href="#concatenation">Concatenation</a></li>
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68 <li><a href="#length">The Length Operator</a></li>
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69 <li><a href="#precedence">Precedence</a></li>
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70 <li><a href="#constructors">Table Constructors</a></li>
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71 <li><a href="#fn_calls">Function Calls</a></li>
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72 <li><a href="#fn_def">Function Definitions</a></li>
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73 </ul>
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74 </li>
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75 <li><a href="#visibility">Visibility Rules</a></li>
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76 </ul>
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77 </div>
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78
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79 <div contents>
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80 <a href="#libs">Standard Libraries</a>
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81 <ul>
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82 <li><a href="#default_lib">Default Environment</a></li>
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83 <li><a href="#luan_lib">Basic Functions</a></li>
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84 <li><a href="#package_lib">Modules</a></li>
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85 <li><a href="#string_lib">String Manipulation</a></li>
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86 <li><a href="#binary_lib">Binary Manipulation</a></li>
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87 <li><a href="#table_lib">Table Manipulation</a></li>
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88 <li><a href="#number_lib">Number Manipulation</a></li>
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89 <li><a href="#math_lib">Mathematical Functions</a></li>
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90 </ul>
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91 </div>
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92
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93 <hr/>
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94
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95
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96 <h2 heading><a name="intro" href="#intro">Introduction</a></h2>
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97
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98 <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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99
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100 <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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101
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102 <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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104
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105 <h2 heading><a name="basic" href="#basic">Basic Concepts</a></h2>
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106
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107 <p>This section describes the basic concepts of the language.</p>
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108
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109 <h3 heading><a name="types" href="#types">Values and Types</a></h3>
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110
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111 <p>
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112 Luan is a <em>dynamically typed language</em>.
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113 This means that
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114 variables do not have types; only values do.
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115 There are no type definitions in the language.
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116 All values carry their own type.
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119 <p>
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120 All values in Luan are <em>first-class values</em>.
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121 This means that all values can be stored in variables,
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122 passed as arguments to other functions, and returned as results.
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125 <p>
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126 There are eight basic types in Luan:
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127 <em>nil</em>, <em>boolean</em>, <em>number</em>,
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128 <em>string</em>, <em>binary</em>, <em>function</em>, <em>java</em>,
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129 and <em>table</em>.
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130 <em>Nil</em> is the type of the value <b>nil</b>,
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131 whose main property is to be different from any other value;
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132 it usually represents the absence of a useful value.
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133 <em>Nil</em> is implemented as the Java value <em>null</em>.
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134 <em>Boolean</em> is the type of the values <b>false</b> and <b>true</b>.
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135 <em>Boolean</em> is implemented as the Java class <em>Boolean</em>.
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136 <em>Number</em> represents both
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137 integer numbers and real (floating-point) numbers.
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138 <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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139 the underlying Java implementation.
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140
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141 <em>String</em> is implemented as the Java class <em>String</em>.
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142 <em>Binary</em> is implemented as the Java type <em>byte[]</em>.
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144
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145 <p>
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146 Luan can call (and manipulate) functions written in Luan and
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147 functions written in Java (see <a href="#fn_calls">Function Calls</a>).
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148 Both are represented by the type <em>function</em>.
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149
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150
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151 <p>
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152 The type <em>java</em> is provided to allow arbitrary Java objects to
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153 be stored in Luan variables.
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154 A <em>java</em> value is a Java object that isn't one of the standard Luan types.
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155 Java values have no predefined operations in Luan,
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156 except assignment and identity test.
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157 Java values are useful when Java access is enabled in Luan
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158
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159
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160
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161 <p>
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162 The type <em>table</em> implements associative arrays,
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163 that is, arrays that can be indexed not only with numbers,
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164 but with any Luan value except <b>nil</b>.
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165 Tables can be <em>heterogeneous</em>;
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166 that is, they can contain values of all types (except <b>nil</b>).
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167 Any key with value <b>nil</b> is not considered part of the table.
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168 Conversely, any key that is not part of a table has
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169 an associated value <b>nil</b>.
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170
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171
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172 <p>
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173 Tables are the sole data-structuring mechanism in Luan;
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174 they can be used to represent ordinary arrays, sequences,
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175 symbol tables, sets, records, graphs, trees, etc.
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176 To represent records, Luan uses the field name as an index.
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177 The language supports this representation by
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178 providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
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179 There are several convenient ways to create tables in Luan
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180 (see <a href="#constructors">Table Constructors</a>).
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181
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182
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183 <p>
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184 We use the term <em>sequence</em> to denote a table where
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185 the set of all positive numeric keys is equal to {1..<em>n</em>}
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186 for some non-negative integer <em>n</em>,
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187 which is called the length of the sequence (see <a href="#length">The Length Operator</a>).
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188
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189
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190 <p>
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191 Like indices,
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192 the values of table fields can be of any type.
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193 In particular,
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194 because functions are first-class values,
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195 table fields can contain functions.
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196 Thus tables can also carry <em>methods</em> (see <a href="#fn_def">Function Definitions</a>).
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197
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198
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199 <p>
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200 The indexing of tables follows
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201 the definition of raw equality in the language.
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202 The expressions <code>a[i]</code> and <code>a[j]</code>
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203 denote the same table element
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204 if and only if <code>i</code> and <code>j</code> are raw equal
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205 (that is, equal without metamethods).
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206 In particular, floats with integral values
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207 are equal to their respective integers
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208 (e.g., <code>1.0 == 1</code>).
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209
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210
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211 <p>
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212 Luan values are <em>objects</em>:
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213 variables do not actually <em>contain</em> values,
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214 only <em>references</em> to them.
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215 Assignment, parameter passing, and function returns
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216 always manipulate references to values;
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217 these operations do not imply any kind of copy.
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218
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219
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220 <p>
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221 The library function <a href="#Luan.type"><code>Luan.type</code></a> returns a string describing the type
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222 of a given value.
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223
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227
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228 <h3 heading><a name="env" href="#env">Environments</a></h3>
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229
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230 <p>
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231 The environment of a chunk starts with only one local variable: <code><a href="#require">require</a></code>. This function is used to load and access libraries and other modules. All other variables must be added to the environment using <a href="http://localhost:8080/manual.html#local_stmt">local declarations</a>.
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232
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233 <p>
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234 As will be discussed in <a href="#vars">Variables</a> and <a href=#assignment">Assignment</a>,
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235 any reference to a free name
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236 (that is, a name not bound to any declaration) <code>var</code>
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237 can be syntactically translated to <code>_ENV.var</code> if <code>_ENV</code> is defined.
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238
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239
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240 <h3 heading><a name="error" href="#error">Error Handling</a></h3>
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241
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242 <p>
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243 Luan code can explicitly generate an error by calling the
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244 <a href="#Luan.error"><code>error</code></a> function.
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245 If you need to catch errors in Luan,
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246 you can use <a href="#Luan.pcall"><code>pcall</code></a> or <a href="#Luan.try"><code>try</code></a>
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247 to call a given function in <em>protected mode</em>.
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248
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249
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250 <p>
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251 Whenever there is an error,
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252 an <em>error table</em>
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253 is propagated with information about the error.
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254 See <a href="#Luan.new_error"><code>Luan.new_error</code></a>.
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255
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256
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257
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258 <h3 heading><a name="meta" href="#meta">Metatables and Metamethods</a></h3>
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259
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260 <p>
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261 Every table in Luan can have a <em>metatable</em>.
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262 This <em>metatable</em> is an ordinary Luan table
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263 that defines the behavior of the original value
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264 under certain special operations.
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265 You can change several aspects of the behavior
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266 of operations over a value by setting specific fields in its metatable.
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267 For instance, when a table is the operand of an addition,
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268 Luan checks for a function in the field "<code>__add</code>" of the table's metatable.
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269 If it finds one,
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270 Luan calls this function to perform the addition.
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271
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272
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273 <p>
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274 The keys in a metatable are derived from the <em>event</em> names;
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275 the corresponding values are called <ii>metamethods</em>.
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276 In the previous example, the event is <code>"add"</code>
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277 and the metamethod is the function that performs the addition.
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278
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279
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280 <p>
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281 You can query the metatable of any table
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282 using the <a href="#Luan.get_metatable"><code>get_metatable</code></a> function.
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284
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285 <p>
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286 You can replace the metatable of tables
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287 using the <a href="#Luan.set_metatable"><code>set_metatable</code></a> function.
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288
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289
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290 <p>
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291 A metatable controls how a table behaves in
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292 arithmetic operations, bitwise operations,
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293 order comparisons, concatenation, length operation, calls, and indexing.
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294
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296 <p>
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297 A detailed list of events controlled by metatables is given next.
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298 Each operation is identified by its corresponding event name.
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299 The key for each event is a string with its name prefixed by
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300 two underscores, '<code>__</code>';
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301 for instance, the key for operation "add" is the
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302 string "<code>__add</code>".
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303 Note that queries for metamethods are always raw;
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304 the access to a metamethod does not invoke other metamethods.
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305 You can emulate how Luan queries a metamethod for an object <code>obj</code>
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306 with the following code:
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307
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308 <pre>
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309 raw_get(get_metatable(obj) or {}, "__" .. event_name)
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310 </pre>
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311
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312 <p>
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313 Here are the events:
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314
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315 <ul>
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316
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317 <li><p><b>"add": </b>
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318 the <code>+</code> operation.
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319
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320 If any operand for an addition is a table,
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321 Luan will try to call a metamethod.
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322 First, Luan will check the first operand (even if it is valid).
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323 If that operand does not define a metamethod for the "<code>__add</code>" event,
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324 then Luan will check the second operand.
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325 If Luan can find a metamethod,
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326 it calls the metamethod with the two operands as arguments,
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327 and the result of the call
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328 (adjusted to one value)
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329 is the result of the operation.
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330 Otherwise,
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331 it raises an error.
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332 </li>
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333
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334 <li><p><b>"sub": </b>
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335 the <code>-</code> operation.
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336
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337 Behavior similar to the "add" operation.
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338 </li>
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339
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340 <li><p><b>"mul": </b>
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341 the <code>*</code> operation.
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342
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343 Behavior similar to the "add" operation.
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344 </li>
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345
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346 <li><p><b>"div": </b>
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347 the <code>/</code> operation.
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348
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349 Behavior similar to the "add" operation.
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350 </li>
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351
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352 <li><p><b>"mod": </b>
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353 the <code>%</code> operation.
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354
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355 Behavior similar to the "add" operation.
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356 </li>
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357
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358 <li><p><b>"pow": </b>
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359 the <code>^</code> (exponentiation) operation.
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360
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361 Behavior similar to the "add" operation.
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362 </li>
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363
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364 <li><p><b>"unm": </b>
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365 the <code>-</code> (unary minus) operation.
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366
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367 Behavior similar to the "add" operation.
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368 </li>
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369
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370 <li><p><b>"concat": </b>
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371 the <code>..</code> (concatenation) operation.
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372
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373 Behavior similar to the "add" operation.
371
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374 </li>
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375
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376 <li><p><b>"len": </b>
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377 the <code>#</code> (length) operation.
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378
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379 If there is a metamethod,
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380 Luan calls it with the object as argument,
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381 and the result of the call
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382 (always adjusted to one value)
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383 is the result of the operation.
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384 If there is no metamethod but the object is a table,
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385 then Luan uses the table length operation (see <a href="#length">The Length Operator</a>).
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386 Otherwise, Luan raises an error.
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387 </li>
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388
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389 <li><p><b>"eq": </b>
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390 the <code>==</code> (equal) operation.
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391
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392 Behavior similar to the "add" operation,
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393 except that Luan will try a metamethod only when the values
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394 being compared are both tables
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395 and they are not primitively equal.
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396 The result of the call is always converted to a boolean.
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397 </li>
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398
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399 <li><p><b>"lt": </b>
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400 the <code>&lt;</code> (less than) operation.
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401
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402 Behavior similar to the "add" operation.
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403 The result of the call is always converted to a boolean.
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404 </li>
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405
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406 <li><p><b>"le": </b>
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407 the <code>&lt;=</code> (less equal) operation.
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408
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409 Unlike other operations,
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410 The less-equal operation can use two different events.
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411 First, Luan looks for the "<code>__le</code>" metamethod in both operands,
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412 like in the "lt" operation.
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413 If it cannot find such a metamethod,
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414 then it will try the "<code>__lt</code>" event,
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415 assuming that <code>a &lt;= b</code> is equivalent to <code>not (b &lt; a)</code>.
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416 As with the other comparison operators,
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417 the result is always a boolean.
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418 </li>
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419
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420 <li><p><b>"index": </b>
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421 The indexing access <code>table[key]</code>.
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422
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423 This event happens
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424 when <code>key</code> is not present in <code>table</code>.
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425 The metamethod is looked up in <code>table</code>.
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426
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427
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428 <p>
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429 Despite the name,
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430 the metamethod for this event can be any type.
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431 If it is a function,
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432 it is called with <code>table</code> and <code>key</code> as arguments.
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433 Otherwise
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434 the final result is the result of indexing this metamethod object with <code>key</code>.
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435 (This indexing is regular, not raw,
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436 and therefore can trigger another metamethod if the metamethod object is a table.)
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437 </li>
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438
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439 <li><p><b>"new_index": </b>
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440 The indexing assignment <code>table[key] = value</code>.
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441
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442 Like the index event,
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443 this event happens when
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444 when <code>key</code> is not present in <code>table</code>.
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445 The metamethod is looked up in <code>table</code>.
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446
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447
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448 <p>
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449 Like with indexing,
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450 the metamethod for this event can be either a function or a table.
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451 If it is a function,
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452 it is called with <code>table</code>, <code>key</code>, and <code>value</code> as arguments.
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453 If it is a table,
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454 Luan does an indexing assignment to this table with the same key and value.
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455 (This assignment is regular, not raw,
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456 and therefore can trigger another metamethod.)
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457
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458
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459 <p>
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460 Whenever there is a "new_index" metamethod,
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461 Luan does not perform the primitive assignment.
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462 (If necessary,
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463 the metamethod itself can call <a href="#Luan.raw_set"><code>raw_set</code></a>
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464 to do the assignment.)
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465 </li>
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466
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467 <li><p><b>"gc":</b>
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468 This is when a table is garbage collected. When the table's <a href="https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#finalize()">finalize</a> method is called by the Java garbage collector, if there is a "<code>__gc</code>" metamethod then it is called with the table as a parameter.
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469
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470 </li>
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471
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472 </ul>
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473
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474
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475
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476
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477 <h3 heading><a name="gc" href="#gc">Garbage Collection</a></h3>
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478
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479 <p>
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480 Luan uses Java's garbage collection.
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481
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482
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diff changeset
483
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484
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485
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486 <h2 heading><a name="lang" href="#lang">The Language</a></h2>
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487
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488 <p>
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489 This section describes the lexis, the syntax, and the semantics of Luan.
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490 In other words,
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491 this section describes
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492 which tokens are valid,
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493 how they can be combined,
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494 and what their combinations mean.
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495
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496
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497 <p>
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498 Language constructs will be explained using the usual extended BNF notation,
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499 in which
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500 {<em>a</em>}&nbsp;means&nbsp;0 or more <em>a</em>'s, and
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501 [<em>a</em>]&nbsp;means an optional <em>a</em>.
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502 Non-terminals are shown like non-terminal,
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503 keywords are shown like <b>kword</b>,
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504 and other terminal symbols are shown like &lsquo;<b>=</b>&rsquo;.
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505 The complete syntax of Luan can be found in <a href="#9">&sect;9</a>
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506 at the end of this manual.
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507
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508
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509
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510 <h3 heading><a name="lex" href="#lex">Lexical Conventions</a></h3>
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511
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512 <p>
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513 Luan ignores spaces and comments
371
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514 between lexical elements (tokens),
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515 except as delimiters between names and keywords.
685
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516 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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517
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518 <p>
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519 <em>Names</em>
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520 (also called <em>identifiers</em>)
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521 in Luan can be any string of letters,
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522 digits, and underscores,
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523 not beginning with a digit.
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524 Identifiers are used to name variables, table fields, and labels.
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525
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526
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527 <p>
562
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528 The following <em>keywords</em> are reserved
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529 and cannot be used as names:
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530
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531
562
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532 <pre>
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533 and break do else elseif end
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534 end_do end_for end_function end_if end_while
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535 false for function goto if in
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536 local nil not or repeat return
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537 then true until while
562
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538 </pre>
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539
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540 <p>
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541 Luan is a case-sensitive language:
562
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542 <code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
371
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543 are two different, valid names.
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544
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545
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546 <p>
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547 The following strings denote other tokens:
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548
562
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549 <pre>
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550 + - * / % ^ #
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551 &amp; ~ | &lt;&lt; &gt;&gt; //
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552 == ~= &lt;= &gt;= &lt; &gt; =
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553 ( ) { } [ ] ::
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554 ; : , . .. ...
562
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555 </pre>
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556
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557 <p>
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558 <em>Literal strings</em>
371
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559 can be delimited by matching single or double quotes,
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560 and can contain the following C-like escape sequences:
562
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561 '<code>\a</code>' (bell),
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562 '<code>\b</code>' (backspace),
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563 '<code>\f</code>' (form feed),
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564 '<code>\n</code>' (newline),
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565 '<code>\r</code>' (carriage return),
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566 '<code>\t</code>' (horizontal tab),
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567 '<code>\v</code>' (vertical tab),
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568 '<code>\\</code>' (backslash),
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569 '<code>\"</code>' (quotation mark [double quote]),
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570 and '<code>\'</code>' (apostrophe [single quote]).
371
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571 A backslash followed by a real newline
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572 results in a newline in the string.
562
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573 The escape sequence '<code>\z</code>' skips the following span
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574 of white-space characters,
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575 including line breaks;
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576 it is particularly useful to break and indent a long literal string
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577 into multiple lines without adding the newlines and spaces
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578 into the string contents.
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579
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580
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581 <p>
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582 Luan can specify any character in a literal string by its numerical value.
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583 This can be done
562
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584 with the escape sequence <code>\x<em>XX</em></code>,
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585 where <em>XX</em> is a sequence of exactly two hexadecimal digits,
793
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586 or with the escape sequence <code>\u<em>XXXX</em></code>,
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587 where <em>XXXX</em> is a sequence of exactly four hexadecimal digits,
562
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588 or with the escape sequence <code>\<em>ddd</em></code>,
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589 where <em>ddd</em> is a sequence of up to three decimal digits.
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590 (Note that if a decimal escape sequence is to be followed by a digit,
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591 it must be expressed using exactly three digits.)
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592
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593
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594 <p>
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595 Literal strings can also be defined using a long format
562
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diff changeset
596 enclosed by <em>long brackets</em>.
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597 We define an <em>opening long bracket of level <em>n</em></em> as an opening
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598 square bracket followed by <em>n</em> equal signs followed by another
371
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599 opening square bracket.
562
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diff changeset
600 So, an opening long bracket of level 0 is written as <code>[[</code>,
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601 an opening long bracket of level 1 is written as <code>[=[</code>,
371
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602 and so on.
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603 A <em>closing long bracket</em> is defined similarly;
371
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604 for instance,
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605 a closing long bracket of level 4 is written as <code>]====]</code>.
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606 A <em>long literal</em> starts with an opening long bracket of any level and
371
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607 ends at the first closing long bracket of the same level.
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608 It can contain any text except a closing bracket of the same level.
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609 Literals in this bracketed form can run for several lines,
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610 do not interpret any escape sequences,
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611 and ignore long brackets of any other level.
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612 Any kind of end-of-line sequence
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613 (carriage return, newline, carriage return followed by newline,
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614 or newline followed by carriage return)
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615 is converted to a simple newline.
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616
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617
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618 <p>
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diff changeset
619 Any character in a literal string not
371
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620 explicitly affected by the previous rules represents itself.
380
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diff changeset
621 However, Luan opens files for parsing in text mode,
371
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622 and the system file functions may have problems with
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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623 some control characters.
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624 So, it is safer to represent
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625 non-text data as a quoted literal with
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626 explicit escape sequences for non-text characters.
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627
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628
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629 <p>
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630 For convenience,
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631 when the opening long bracket is immediately followed by a newline,
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632 the newline is not included in the string.
380
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633 As an example
371
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634 the five literal strings below denote the same string:
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635
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636 <pre>
371
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637 a = 'alo\n123"'
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638 a = "alo\n123\""
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639 a = '\97lo\10\04923"'
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640 a = [[alo
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641 123"]]
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642 a = [==[
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643 alo
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644 123"]==]
562
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diff changeset
645 </pre>
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646
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647 <p>
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diff changeset
648 A <em>numerical constant</em> (or <em>numeral</em>)
371
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649 can be written with an optional fractional part
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650 and an optional decimal exponent,
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651 marked by a letter '<code>e</code>' or '<code>E</code>'.
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652 Luan also accepts hexadecimal constants,
562
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653 which start with <code>0x</code> or <code>0X</code>.
371
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654 Hexadecimal constants also accept an optional fractional part
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655 plus an optional binary exponent,
562
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656 marked by a letter '<code>p</code>' or '<code>P</code>'.
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657 A numeric constant with a fractional dot or an exponent
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658 denotes a float;
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659 otherwise it denotes an integer.
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660 Examples of valid integer constants are
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661
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662 <pre>
371
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663 3 345 0xff 0xBEBADA
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diff changeset
664 </pre>
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665
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666 <p>
371
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667 Examples of valid float constants are
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668
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diff changeset
669 <pre>
371
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670 3.0 3.1416 314.16e-2 0.31416E1 34e1
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671 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562
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diff changeset
672 </pre>
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diff changeset
673
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674 <p>
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diff changeset
675 A <em>comment</em> starts with a double hyphen (<code>--</code>)
371
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676 anywhere outside a string.
562
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677 If the text immediately after <code>--</code> is not an opening long bracket,
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678 the comment is a <em>short comment</em>,
371
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679 which runs until the end of the line.
562
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diff changeset
680 Otherwise, it is a <em>long comment</em>,
371
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681 which runs until the corresponding closing long bracket.
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682 Long comments are frequently used to disable code temporarily.
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parents:
diff changeset
683
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
684
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
685
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
686
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
687
1327
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diff changeset
688 <h3 heading><a name="vars" href="#vars">Variables</a></h3>
371
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diff changeset
689
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parents:
diff changeset
690 <p>
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691 Variables are places that store values.
380
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diff changeset
692 There are three kinds of variables in Luan:
371
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693 global variables, local variables, and table fields.
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parents:
diff changeset
694
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parents:
diff changeset
695 <p>
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diff changeset
696 A single name can denote a global variable or a local variable
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697 (or a function's formal parameter,
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698 which is a particular kind of local variable):
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699
562
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700 <pre>
371
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701 var ::= Name
562
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diff changeset
702 </pre>
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diff changeset
703
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704 <p>
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diff changeset
705 Name denotes identifiers, as defined in <a href="#lex">Lexical Conventions</a>.
371
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706
512
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parents: 505
diff changeset
707 <p>
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diff changeset
708 Local variables are <em>lexically scoped</em>:
371
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709 local variables can be freely accessed by functions
464
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710 defined inside their scope (see <a href="#visibility">Visibility Rules</a>).
371
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711
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parents:
diff changeset
712
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
713 <p>
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parents:
diff changeset
714 Before the first assignment to a variable, its value is <b>nil</b>.
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parents:
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715
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parents:
diff changeset
716 <p>
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parents:
diff changeset
717 Square brackets are used to index a table:
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parents:
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718
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diff changeset
719 <pre>
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720 var ::= prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo;
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diff changeset
721 </pre>
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722
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diff changeset
723 <p>
371
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724 The meaning of accesses to table fields can be changed via metatables.
562
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725 An access to an indexed variable <code>t[i]</code> is equivalent to
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726 a call <code>gettable_event(t,i)</code>.
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727 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562
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diff changeset
728 <code>gettable_event</code> function.
380
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729 This function is not defined or callable in Luan.
371
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diff changeset
730 We use it here only for explanatory purposes.)
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diff changeset
731
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
732
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diff changeset
733 <p>
562
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diff changeset
734 The syntax <code>var.Name</code> is just syntactic sugar for
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diff changeset
735 <code>var["Name"]</code>:
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diff changeset
736
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737 <pre>
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738 var ::= prefixexp &lsquo;<b>.</b>&rsquo; Name
562
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diff changeset
739 </pre>
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diff changeset
740
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diff changeset
741 <p>
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diff changeset
742 Global variables are not available by default. To enable global variable, you must define <code>_ENV</code> as a local variable whose value is a table. If <code>_ENV</code> is not defined, then an unrecognized variable name will produce a compile error. If <code>_ENV</code> is defined then an access to an unrecognized variable name will be consider a global variable. So then an acces to global variable <code>x</code>
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743 is equivalent to <code>_ENV.x</code>.
371
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744 Due to the way that chunks are compiled,
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745 <code>_ENV</code> is never a global name (see <a href="#env">Environments</a>).
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746
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diff changeset
747
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diff changeset
748
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diff changeset
749
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diff changeset
750
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751 <h3 heading><a name="stmts" href="#stmts">Statements</a></h3>
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752
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753 <p>
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754 Luan supports an almost conventional set of statements,
371
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755 similar to those in Pascal or C.
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756 This set includes
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757 assignments, control structures, function calls,
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758 and variable declarations.
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759
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760
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761
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762 <h4 heading><a name="blocks" href="#blocks">Blocks</a></h4>
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763
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764 <p>
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765 A block is a list of statements,
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766 which are executed sequentially:
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767
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768 <pre>
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769 block ::= {stat}
562
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diff changeset
770 </pre>
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diff changeset
771
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diff changeset
772 <p>
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773 Luan has <em>empty statements</em>
371
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774 that allow you to separate statements with semicolons,
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775 start a block with a semicolon
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776 or write two semicolons in sequence:
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777
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diff changeset
778 <pre>
371
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779 stat ::= &lsquo;<b>;</b>&rsquo;
562
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diff changeset
780 </pre>
371
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781
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782 <p>
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783 A block can be explicitly delimited to produce a single statement:
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784
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diff changeset
785 <pre>
1092
a26fbde7ee28 documentation
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diff changeset
786 stat ::= <b>do</b> block end_do
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diff changeset
787 end_do ::= <b>end_do</b> | <b>end</b>
562
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788 </pre>
389
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diff changeset
789
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790 <p>
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diff changeset
791 Explicit blocks are useful
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792 to control the scope of variable declarations.
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793 Explicit blocks are also sometimes used to
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794 add a <b>return</b> statement in the middle
464
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795 of another block (see <a href="#control">Control Structures</a>).
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
796
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
797
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
798
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
799
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
800
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801 <h4 heading><a name="chunks" href="#chunks">Chunks</a></h4>
562
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diff changeset
802
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diff changeset
803 <p>
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diff changeset
804 The unit of compilation of Luan is called a <em>chunk</em>.
371
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805 Syntactically,
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806 a chunk is simply a block:
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diff changeset
807
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diff changeset
808 <pre>
371
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809 chunk ::= block
562
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diff changeset
810 </pre>
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diff changeset
811
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812 <p>
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diff changeset
813 Luan handles a chunk as the body of an anonymous function
371
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814 with a variable number of arguments
464
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diff changeset
815 (see <a href="#fn_def">Function Definitions</a>).
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816 As such, chunks can define local variables,
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817 receive arguments, and return values.
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diff changeset
818
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parents:
diff changeset
819
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diff changeset
820 <p>
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diff changeset
821 A chunk can be stored in a file or in a string inside the host program.
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822 To execute a chunk,
562
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diff changeset
823 Luan first <em>loads</em> it,
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diff changeset
824 compiling the chunk's code,
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825 and then Luan executes the compiled code.
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diff changeset
826
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diff changeset
827
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diff changeset
828
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diff changeset
829
a7cb58532846 work on manual
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diff changeset
830
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831 <h4 heading><a name="assignment" href="#assignment">Assignment</a></h4>
395
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diff changeset
832
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833 <p>
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834 Luan allows multiple assignments.
371
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835 Therefore, the syntax for assignment
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diff changeset
836 defines a list of variables on the left side
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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837 and a list of expressions on the right side.
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838 The elements in both lists are separated by commas:
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diff changeset
839
562
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diff changeset
840 <pre>
371
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diff changeset
841 stat ::= varlist &lsquo;<b>=</b>&rsquo; explist
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parents:
diff changeset
842 varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
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diff changeset
843 explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
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diff changeset
844 </pre>
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diff changeset
845
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846 <p>
464
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diff changeset
847 Expressions are discussed in <a href="#expressions">Expressions</a>.
371
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diff changeset
848
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parents:
diff changeset
849
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
850 <p>
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diff changeset
851 Before the assignment,
562
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852 the list of values is <em>adjusted</em> to the length of
371
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853 the list of variables.
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diff changeset
854 If there are more values than needed,
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855 the excess values are thrown away.
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diff changeset
856 If there are fewer values than needed,
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857 the list is extended with as many <b>nil</b>'s as needed.
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858 If the list of expressions ends with a function call,
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859 then all values returned by that call enter the list of values,
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860 before the adjustment
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diff changeset
861 (except when the call is enclosed in parentheses; see <a href="#expressions">Expressions</a>).
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862
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
863
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
864 <p>
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diff changeset
865 The assignment statement first evaluates all its expressions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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866 and only then the assignments are performed.
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867 Thus the code
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868
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diff changeset
869 <pre>
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870 i = 3
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871 i, a[i] = i+1, 20
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872 </pre>
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diff changeset
873
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874 <p>
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diff changeset
875 sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
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876 because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
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877 before it is assigned&nbsp;4.
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878 Similarly, the line
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879
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880 <pre>
371
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diff changeset
881 x, y = y, x
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diff changeset
882 </pre>
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diff changeset
883
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diff changeset
884 <p>
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diff changeset
885 exchanges the values of <code>x</code> and <code>y</code>,
371
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diff changeset
886 and
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diff changeset
887
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diff changeset
888 <pre>
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889 x, y, z = y, z, x
562
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diff changeset
890 </pre>
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diff changeset
891
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diff changeset
892 <p>
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diff changeset
893 cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</code>.
371
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diff changeset
894
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diff changeset
895
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896 <p>
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897 The meaning of assignments to global variables
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898 and table fields can be changed via metatables.
562
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899 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
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900 <code>settable_event(t,i,val)</code>.
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901 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
562
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902 <code>settable_event</code> function.
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903 This function is not defined or callable in Luan.
371
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904 We use it here only for explanatory purposes.)
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905
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906
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907 <p>
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diff changeset
908 An assignment to a global name <code>x = val</code>
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909 is equivalent to the assignment
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910 <code>_ENV.x = val</code> (see <a href="#env">Environments</a>).
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911 Global names are only available when <code>_ENV</code> is defined.
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912
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diff changeset
913
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diff changeset
914
1327
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915 <h4 heading><a name="control" href="#control">Control Structures</a></h4>
395
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diff changeset
916
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917 <p>
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918 The control structures
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919 <b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and
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920 familiar syntax:
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921
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922 <pre>
1092
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923 stat ::= <b>while</b> exp <b>do</b> block end_while
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924 stat ::= <b>repeat</b> block <b>until</b> exp
1092
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925 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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diff changeset
926 end_while ::= <b>end_while</b> | <b>end</b>
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diff changeset
927 end_if ::= <b>end_if</b> | <b>end</b>
562
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diff changeset
928 </pre>
395
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diff changeset
929
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930 <p>
464
eddf7c73373b fix references in the manual
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diff changeset
931 Luan also has a <b>for</b> statement (see <a href="#for">For Statement</a>).
371
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932
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933
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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934 <p>
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935 The condition expression of a
395
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diff changeset
936 control structure must be a boolean.
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937 Any other value type will produce an error.
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diff changeset
938 This helps catch errors and makes code more readable.
371
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diff changeset
939
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diff changeset
940
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diff changeset
941 <p>
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diff changeset
942 In the <b>repeat</b>&ndash;<b>until</b> loop,
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943 the inner block does not end at the <b>until</b> keyword,
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944 but only after the condition.
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diff changeset
945 So, the condition can refer to local variables
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946 declared inside the loop block.
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diff changeset
947
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948
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diff changeset
949 <p>
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950 The <b>break</b> statement terminates the execution of a
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951 <b>while</b>, <b>repeat</b>, or <b>for</b> loop,
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952 skipping to the next statement after the loop:
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diff changeset
953
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954
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955 <pre>
371
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956 stat ::= <b>break</b>
562
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diff changeset
957 </pre>
395
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diff changeset
958
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diff changeset
959 <p>
371
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960 A <b>break</b> ends the innermost enclosing loop.
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diff changeset
961
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diff changeset
962
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963 <p>
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diff changeset
964 The <b>return</b> statement is used to return values
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965 from a function or a chunk
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diff changeset
966 (which is an anonymous function).
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967
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diff changeset
968 Functions can return more than one value,
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969 so the syntax for the <b>return</b> statement is
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diff changeset
970
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971 <pre>
371
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diff changeset
972 stat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
562
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diff changeset
973 </pre>
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parents: 556
diff changeset
974
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diff changeset
975
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diff changeset
976
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diff changeset
977
1327
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diff changeset
978 <h4 heading><a name="for" href="#for">For Statement</a></h4>
395
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diff changeset
979
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diff changeset
980 <p>
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diff changeset
981 The <b>for</b> statement works over functions,
562
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diff changeset
982 called <em>iterators</em>.
395
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diff changeset
983 On each iteration, the iterator function is called to produce a new value,
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diff changeset
984 stopping when this new value is <b>nil</b>.
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diff changeset
985 The <b>for</b> loop has the following syntax:
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diff changeset
986
562
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diff changeset
987 <pre>
1092
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parents: 1090
diff changeset
988 stat ::= <b>for</b> namelist <b>in</b> exp <b>do</b> block end_for
395
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diff changeset
989 namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
1092
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parents: 1090
diff changeset
990 end_for ::= <b>end_for</b> | <b>end</b>
562
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991 </pre>
395
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diff changeset
992
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993 <p>
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diff changeset
994 A <b>for</b> statement like
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diff changeset
995
562
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996 <pre>
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997 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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998 </pre>
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diff changeset
999
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1000 <p>
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1001 is equivalent to the code:
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1002
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1003 <pre>
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1004 do
562
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diff changeset
1005 local <em>f</em> = <em>exp</em>
371
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1006 while true do
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diff changeset
1007 local <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> = <em>f</em>()
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1008 if <em>var_1</em> == nil then break end
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diff changeset
1009 <em>block</em>
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1010 end
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1011 end
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1012 </pre>
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1013
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diff changeset
1014 <p>
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diff changeset
1015 Note the following:
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parents:
diff changeset
1016
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parents:
diff changeset
1017 <ul>
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diff changeset
1018
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1019 <li>
562
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1020 <code><em>exp</em></code> is evaluated only once.
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diff changeset
1021 Its result is an <em>iterator</em> function.
371
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diff changeset
1022 </li>
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diff changeset
1023
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1024 <li>
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diff changeset
1025 <code><em>f</em></code> is an invisible variable.
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diff changeset
1026 The name is here for explanatory purposes only.
371
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1027 </li>
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diff changeset
1028
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diff changeset
1029 <li>
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1030 You can use <b>break</b> to exit a <b>for</b> loop.
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diff changeset
1031 </li>
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diff changeset
1032
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1033 <li>
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diff changeset
1034 The loop variables <code><em>var_i</em></code> are local to the loop;
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1035 you cannot use their values after the <b>for</b> ends.
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1036 If you need these values,
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diff changeset
1037 then assign them to other variables before breaking or exiting the loop.
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diff changeset
1038 </li>
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diff changeset
1039
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parents:
diff changeset
1040 </ul>
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parents:
diff changeset
1041
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1042
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1043
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1044
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1045 <h4 heading><a name="fn_stmt" href="#fn_stmt">Function Calls as Statements</a></h4>
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1046
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diff changeset
1047 <p>
371
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1048 To allow possible side-effects,
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diff changeset
1049 function calls can be executed as statements:
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1050
562
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1051 <pre>
371
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1052 stat ::= functioncall
562
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diff changeset
1053 </pre>
395
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diff changeset
1054
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diff changeset
1055 <p>
371
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1056 In this case, all returned values are thrown away.
464
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1057 Function calls are explained in <a href="#fn_calls">Function Calls</a>.
371
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1058
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diff changeset
1059
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diff changeset
1060
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1061 <h4 heading><a name="local_stmt" href="#local_stmt">Local Declarations</a></h4>
395
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1062
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diff changeset
1063 <p>
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1064 Local variables can be declared anywhere inside a block.
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diff changeset
1065 The declaration can include an initial assignment:
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1066
562
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1067 <pre>
371
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1068 stat ::= <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist]
562
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1069 </pre>
395
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diff changeset
1070
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1071 <p>
371
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1072 If present, an initial assignment has the same semantics
464
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1073 of a multiple assignment (see <a href="#assignment">Assignment</a>).
371
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1074 Otherwise, all variables are initialized with <b>nil</b>.
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diff changeset
1075
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parents:
diff changeset
1076
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1077 <p>
464
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1078 A chunk is also a block (see <a href="#chunks">Chunks</a>),
371
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1079 and so local variables can be declared in a chunk outside any explicit block.
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diff changeset
1080
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parents:
diff changeset
1081
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1082 <p>
464
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diff changeset
1083 The visibility rules for local variables are explained in <a href="#visibility">Visibility Rules</a>.
371
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1084
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1085
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1086 <h4 heading><a name="template_stmt" href="#template_stmt">Template Statements</a></h4>
465
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1087
1384
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1088 <p>Template statements provide the full equivalent of <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a> but in a general way. Template statements write to standard output. For example:</p>
465
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diff changeset
1089
1325
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1090 <pre>
465
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diff changeset
1091 local name = "Bob"
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1092 %>
469
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diff changeset
1093 Hello <%= name %>!
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diff changeset
1094 Bye <%= name %>.
465
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1095 <%
1325
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1096 </pre>
465
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diff changeset
1097
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1098 <p>is equivalent to the code:</p>
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1099
1325
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1100 <pre>
465
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diff changeset
1101 local name = "Bob"
1384
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diff changeset
1102 require("luan:Io.luan").stdout.write( "Hello ", name , "!\nBye ", name , ".\n" )
1325
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1103 </pre>
562
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parents: 556
diff changeset
1104
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parents: 556
diff changeset
1105
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diff changeset
1106
1327
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1107 <h3 heading><a name="expressions" href="#expressions">Expressions</a></h3>
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diff changeset
1108
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1109 <p>
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1110 The basic expressions in Luan are the following:
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1111
562
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1112 <pre>
371
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1113 exp ::= prefixexp
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diff changeset
1114 exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
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diff changeset
1115 exp ::= Numeral
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diff changeset
1116 exp ::= LiteralString
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diff changeset
1117 exp ::= functiondef
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diff changeset
1118 exp ::= tableconstructor
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diff changeset
1119 exp ::= &lsquo;<b>...</b>&rsquo;
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diff changeset
1120 exp ::= exp binop exp
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diff changeset
1121 exp ::= unop exp
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1122 prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
562
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diff changeset
1123 </pre>
371
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diff changeset
1124
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diff changeset
1125 <p>
464
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diff changeset
1126 Numerals and literal strings are explained in <a href="#lex">Lexical Conventions</a>;
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diff changeset
1127 variables are explained in <a href="#vars">Variables</a>;
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diff changeset
1128 function definitions are explained in <a href="#fn_def">Function Definitions</a>;
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diff changeset
1129 function calls are explained in <a href="#fn_calls">Function Calls</a>;
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diff changeset
1130 table constructors are explained in <a href="#constructors">Table Constructors</a>.
371
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1131 Vararg expressions,
562
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1132 denoted by three dots ('<code>...</code>'), can only be used when
371
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1133 directly inside a vararg function;
464
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diff changeset
1134 they are explained in <a href="#fn_def">Function Definitions</a>.
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diff changeset
1135
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diff changeset
1136
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diff changeset
1137 <p>
eddf7c73373b fix references in the manual
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diff changeset
1138 Binary operators comprise arithmetic operators (see <a href="#arithmetic">Arithmetic Operators</a>),
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diff changeset
1139 relational operators (see <a href="#relational">Relational Operators</a>), logical operators (see <a href="#logical_ops">Logical Operators</a>),
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1140 and the concatenation operator (see <a href="#concatenation">Concatenation</a>).
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diff changeset
1141 Unary operators comprise the unary minus (see <a href="#arithmetic">Arithmetic Operators</a>),
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parents: 429
diff changeset
1142 the unary logical <b>not</b> (see <a href="#logical_ops">Logical Operators</a>),
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diff changeset
1143 and the unary <em>length operator</em> (see <a href="#length">The Length Operator</a>).
371
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1144
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diff changeset
1145
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diff changeset
1146 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1147 Both function calls and vararg expressions can result in multiple values.
464
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diff changeset
1148 If a function call is used as a statement (see <a href="#fn_stmt">Function Calls as Statements</a>),
371
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1149 then its return list is adjusted to zero elements,
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1150 thus discarding all returned values.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1151 If an expression is used as the last (or the only) element
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diff changeset
1152 of a list of expressions,
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1153 then no adjustment is made
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1154 (unless the expression is enclosed in parentheses).
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1155 In all other contexts,
395
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1156 Luan adjusts the result list to one element,
371
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diff changeset
1157 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
1158 or adding a single <b>nil</b> if there are no values.
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parents:
diff changeset
1159
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diff changeset
1160
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diff changeset
1161 <p>
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diff changeset
1162 Here are some examples:
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1163
562
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1164 <pre>
371
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diff changeset
1165 f() -- adjusted to 0 results
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diff changeset
1166 g(f(), x) -- f() is adjusted to 1 result
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diff changeset
1167 g(x, f()) -- g gets x plus all results from f()
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diff changeset
1168 a,b,c = f(), x -- f() is adjusted to 1 result (c gets nil)
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1169 a,b = ... -- a gets the first vararg parameter, b gets
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1170 -- the second (both a and b can get nil if there
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1171 -- is no corresponding vararg parameter)
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1172
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diff changeset
1173 a,b,c = x, f() -- f() is adjusted to 2 results
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parents:
diff changeset
1174 a,b,c = f() -- f() is adjusted to 3 results
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1175 return f() -- returns all results from f()
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1176 return ... -- returns all received vararg parameters
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1177 return x,y,f() -- returns x, y, and all results from f()
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1178 {f()} -- creates a list with all results from f()
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diff changeset
1179 {...} -- creates a list with all vararg parameters
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1180 {f(), nil} -- f() is adjusted to 1 result
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1181 </pre>
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1182
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1183 <p>
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1184 Any expression enclosed in parentheses always results in only one value.
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1185 Thus,
562
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1186 <code>(f(x,y,z))</code> is always a single value,
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1187 even if <code>f</code> returns several values.
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1188 (The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
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1189 or <b>nil</b> if <code>f</code> does not return any values.)
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1190
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diff changeset
1191
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1192
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1193 <h4 heading><a name="arithmetic" href="#arithmetic">Arithmetic Operators</a></h4>
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1194
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1195 <p>
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1196 Luan supports the following arithmetic operators:
371
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1197
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1198 <ul>
562
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1199 <li><b><code>+</code>: </b>addition</li>
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1200 <li><b><code>-</code>: </b>subtraction</li>
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1201 <li><b><code>*</code>: </b>multiplication</li>
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1202 <li><b><code>/</code>: </b>division</li>
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1203 <li><b><code>%</code>: </b>modulo</li>
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1204 <li><b><code>^</code>: </b>exponentiation</li>
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1205 <li><b><code>-</code>: </b>unary minus</li>
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1206 </ul>
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1207
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1208 <p>
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1209 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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1210
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1211 <p>
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1212 Modulo is defined as the remainder of a division
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1213 that rounds the quotient towards minus infinite (floor division).
395
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1214 (The Java modulo operator is not used.)
371
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1215
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diff changeset
1216
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1217
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1218 <h4 heading><a name="conversions" href="#conversions">Coercions and Conversions</a></h4>
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1219
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1220 <p>
465
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1221 Luan generally avoids automatic conversions.
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1222 String concatenation automatically converts all of its arguments to strings.
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diff changeset
1223
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1224 <p>
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1225 Luan provides library functions for explicit type conversions.
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1226
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1227
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diff changeset
1228
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diff changeset
1229
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1230 <h4 heading><a name="relational" href="#relational">Relational Operators</a></h4>
396
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1231
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1232 <p>
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1233 Luan supports the following relational operators:
371
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1234
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1235 <ul>
562
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1236 <li><b><code>==</code>: </b>equality</li>
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1237 <li><b><code>~=</code>: </b>inequality</li>
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diff changeset
1238 <li><b><code>&lt;</code>: </b>less than</li>
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1239 <li><b><code>&gt;</code>: </b>greater than</li>
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1240 <li><b><code>&lt;=</code>: </b>less or equal</li>
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1241 <li><b><code>&gt;=</code>: </b>greater or equal</li>
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1242 </ul><p>
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1243 These operators always result in <b>false</b> or <b>true</b>.
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1244
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1245
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1246 <p>
562
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diff changeset
1247 Equality (<code>==</code>) first compares the type of its operands.
371
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1248 If the types are different, then the result is <b>false</b>.
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1249 Otherwise, the values of the operands are compared.
396
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diff changeset
1250 Strings, numbers, and binary values are compared in the obvious way (by value).
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diff changeset
1251
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diff changeset
1252 <p>
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diff changeset
1253 Tables
371
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1254 are compared by reference:
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1255 two objects are considered equal only if they are the same object.
396
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diff changeset
1256 Every time you create a new table,
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1257 it is different from any previously existing table.
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1258 Closures are also compared by reference.
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diff changeset
1259
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diff changeset
1260 <p>
417
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diff changeset
1261 You can change the way that Luan compares tables
464
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diff changeset
1262 by using the "eq" metamethod (see <a href="#meta">Metatables and Metamethods</a>).
371
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1263
396
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diff changeset
1264 <p>
562
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diff changeset
1265 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
1266
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diff changeset
1267 <p>
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diff changeset
1268 Equality comparisons do not convert strings to numbers
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diff changeset
1269 or vice versa.
562
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diff changeset
1270 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
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1271 and <code>t[0]</code> and <code>t["0"]</code> denote different
371
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1272 entries in a table.
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diff changeset
1273
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1274
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1275 <p>
562
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diff changeset
1276 The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
371
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parents:
diff changeset
1277
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1278
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1279 <p>
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1280 The order operators work as follows.
396
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diff changeset
1281
371
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1282 If both arguments are numbers,
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diff changeset
1283 then they are compared following
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diff changeset
1284 the usual rule for binary operations.
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diff changeset
1285 Otherwise, if both arguments are strings,
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1286 then their values are compared according to the current locale.
396
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diff changeset
1287 Otherwise, Luan tries to call the "lt" or the "le"
464
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diff changeset
1288 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562
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diff changeset
1289 A comparison <code>a &gt; b</code> is translated to <code>b &lt; a</code>
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diff changeset
1290 and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
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diff changeset
1291
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diff changeset
1292
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parents: 556
diff changeset
1293
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diff changeset
1294
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diff changeset
1295
1327
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1296 <h4 heading><a name="logical_ops" href="#logical_ops">Logical Operators</a></h4>
396
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diff changeset
1297
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1298 <p>
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diff changeset
1299 The logical operators in Luan are
371
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1300 <b>and</b>, <b>or</b>, and <b>not</b>.
396
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diff changeset
1301 The <b>and</b> and <b>or</b> operators consider both <b>false</b> and <b>nil</b> as false
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1302 and anything else as true.
464
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1303 Like the control structures (see <a href="#control">Control Structures</a>),
396
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1304 the <b>not</b> operator requires a boolean value.
371
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diff changeset
1305
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diff changeset
1306 <p>
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diff changeset
1307 The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>.
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1308 The conjunction operator <b>and</b> returns its first argument
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diff changeset
1309 if this value is <b>false</b> or <b>nil</b>;
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1310 otherwise, <b>and</b> returns its second argument.
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diff changeset
1311 The disjunction operator <b>or</b> returns its first argument
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diff changeset
1312 if this value is different from <b>nil</b> and <b>false</b>;
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1313 otherwise, <b>or</b> returns its second argument.
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diff changeset
1314 Both <b>and</b> and <b>or</b> use short-circuit evaluation;
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1315 that is,
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diff changeset
1316 the second operand is evaluated only if necessary.
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diff changeset
1317 Here are some examples:
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1318
562
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diff changeset
1319 <pre>
371
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diff changeset
1320 10 or 20 --&gt; 10
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diff changeset
1321 10 or error() --&gt; 10
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diff changeset
1322 nil or "a" --&gt; "a"
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diff changeset
1323 nil and 10 --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1324 false and error() --&gt; false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1325 false and nil --&gt; false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1326 false or nil --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1327 10 and 20 --&gt; 20
562
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diff changeset
1328 </pre>
396
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diff changeset
1329
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diff changeset
1330 <p>
371
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diff changeset
1331 (In this manual,
562
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diff changeset
1332 <code>--&gt;</code> indicates the result of the preceding expression.)
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diff changeset
1333
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1334
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1335
1327
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1336 <h4 heading><a name="concatenation" href="#concatenation">Concatenation</a></h4>
396
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diff changeset
1337
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diff changeset
1338 <p>
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diff changeset
1339 The string concatenation operator in Luan is
562
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diff changeset
1340 denoted by two dots ('<code>..</code>').
396
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diff changeset
1341 All operands are converted to strings.
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diff changeset
1342
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diff changeset
1343
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diff changeset
1344
1327
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1345 <h4 heading><a name="length" href="#length">The Length Operator</a></h4>
562
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diff changeset
1346
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diff changeset
1347 <p>
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diff changeset
1348 The length operator is denoted by the unary prefix operator <code>#</code>.
396
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diff changeset
1349 The length of a string is its number of characters.
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diff changeset
1350 The length of a binary is its number of bytes.
371
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diff changeset
1351
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1352
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1353 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1354 A program can modify the behavior of the length operator for
562
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diff changeset
1355 any table through the <code>__len</code> metamethod (see <a href="#meta">Metatables and Metamethods</a>).
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diff changeset
1356
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diff changeset
1357
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diff changeset
1358 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1359 Unless a <code>__len</code> metamethod is given,
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1360 the length of a table <code>t</code> is defined
396
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1361 as the number of elements in <em>sequence</em>,
371
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1362 that is,
396
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diff changeset
1363 the size of the set of its positive numeric keys is equal to <em>{1..n}</em>
371
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1364 for some non-negative integer <em>n</em>.
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1365 In that case, <em>n</em> is its length.
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diff changeset
1366 Note that a table like
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1367
562
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diff changeset
1368 <pre>
371
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1369 {10, 20, nil, 40}
562
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diff changeset
1370 </pre>
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diff changeset
1371
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diff changeset
1372 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1373 has a length of <code>2</code>, because that is the last key in sequence.
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diff changeset
1374
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parents: 556
diff changeset
1375
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parents: 556
diff changeset
1376
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1377
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1378
1327
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1379 <h4 heading><a name="precedence" href="#precedence">Precedence</a></h4>
396
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diff changeset
1380
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diff changeset
1381 <p>
ba8b0aae6453 work on manual;
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diff changeset
1382 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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1383 from lower to higher priority:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1384
562
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diff changeset
1385 <pre>
371
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diff changeset
1386 or
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parents:
diff changeset
1387 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1388 &lt; &gt; &lt;= &gt;= ~= ==
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parents:
diff changeset
1389 ..
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1390 + -
396
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diff changeset
1391 * / %
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diff changeset
1392 unary operators (not # -)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1393 ^
562
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diff changeset
1394 </pre>
396
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diff changeset
1395
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diff changeset
1396 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1397 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1398 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
1399 The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
371
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diff changeset
1400 operators are right associative.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1401 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
1402
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1403
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1404
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1405
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1406
1327
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diff changeset
1407 <h4 heading><a name="constructors" href="#constructors">Table Constructors</a></h4>
396
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diff changeset
1408
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diff changeset
1409 <p>
371
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diff changeset
1410 Table constructors are expressions that create tables.
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diff changeset
1411 Every time a constructor is evaluated, a new table is created.
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diff changeset
1412 A constructor can be used to create an empty table
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1413 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
1414 The general syntax for constructors is
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diff changeset
1415
562
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diff changeset
1416 <pre>
604
b73f005f3735 table constructor now uses end_of_line as a delimiter
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parents: 589
diff changeset
1417 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
1418 fieldlist ::= [field] {fieldsep [field]}
371
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parents:
diff changeset
1419 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
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parents: 589
diff changeset
1420 fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo; | <b>end_of_line</b>
562
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diff changeset
1421 </pre>
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parents: 556
diff changeset
1422
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diff changeset
1423 <p>
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diff changeset
1424 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
1425 with key <code>exp1</code> and value <code>exp2</code>.
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diff changeset
1426 A field of the form <code>name = exp</code> is equivalent to
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diff changeset
1427 <code>["name"] = exp</code>.
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diff changeset
1428 Finally, fields of the form <code>exp</code> are equivalent to
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diff changeset
1429 <code>[i] = exp</code>, where <code>i</code> are consecutive integers
371
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diff changeset
1430 starting with 1.
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parents:
diff changeset
1431 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
1432 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1433
562
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diff changeset
1434 <pre>
371
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parents:
diff changeset
1435 a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
562
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diff changeset
1436 </pre>
396
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diff changeset
1437
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diff changeset
1438 <p>
371
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parents:
diff changeset
1439 is equivalent to
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
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parents:
diff changeset
1442 do
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parents:
diff changeset
1443 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1444 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1445 t[1] = "x" -- 1st exp
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1446 t[2] = "y" -- 2nd exp
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parents:
diff changeset
1447 t.x = 1 -- t["x"] = 1
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parents:
diff changeset
1448 t[3] = f(x) -- 3rd exp
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parents:
diff changeset
1449 t[30] = 23
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parents:
diff changeset
1450 t[4] = 45 -- 4th exp
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parents:
diff changeset
1451 a = t
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parents:
diff changeset
1452 end
562
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diff changeset
1453 </pre>
371
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parents:
diff changeset
1454
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parents:
diff changeset
1455 <p>
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parents:
diff changeset
1456 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
1457 (This order would be relevant only when there are repeated keys.)
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parents:
diff changeset
1458
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parents:
diff changeset
1459
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1460 <p>
562
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diff changeset
1461 If the last field in the list has the form <code>exp</code>
371
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diff changeset
1462 and the expression is a function call or a vararg expression,
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parents:
diff changeset
1463 then all values returned by this expression enter the list consecutively
464
eddf7c73373b fix references in the manual
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diff changeset
1464 (see <a href="#fn_calls">Function Calls</a>).
371
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parents:
diff changeset
1465
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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>
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parents:
diff changeset
1468 The field list can have an optional trailing separator,
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parents:
diff changeset
1469 as a convenience for machine-generated code.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1470
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1472
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1473
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1474
1327
b29eefad2111 website - improve docs
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parents: 1326
diff changeset
1475 <h4 heading><a name="fn_calls" href="#fn_calls">Function Calls</a></h4>
417
a40e99cf0b0b work on manual
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diff changeset
1476
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diff changeset
1477 <p>
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1478 A function call in Luan has the following syntax:
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parents: 396
diff changeset
1479
562
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diff changeset
1480 <pre>
371
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parents:
diff changeset
1481 functioncall ::= prefixexp args
562
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parents: 556
diff changeset
1482 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1483
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diff changeset
1484 <p>
371
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diff changeset
1485 In a function call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1486 first prefixexp and args are evaluated.
685
1e4b0bc0202d update documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 642
diff changeset
1487 The value of prefixexp must have type <em>function</em>.
1e4b0bc0202d update documentation
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parents: 642
diff changeset
1488 This function is called
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1489 with the given arguments.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1490
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1491
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1492 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1493 Arguments have the following syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1494
562
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parents: 556
diff changeset
1495 <pre>
371
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Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1496 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
1497 args ::= tableconstructor
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1498 args ::= LiteralString
562
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parents: 556
diff changeset
1499 </pre>
417
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parents: 396
diff changeset
1500
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1501 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1502 All argument expressions are evaluated before the call.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1503 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
1504 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:
diff changeset
1505 that is, the argument list is a single new table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1506 A call of the form <code>f'<em>string</em>'</code>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1507 (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
1508 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
1509 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
1510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1511
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1512
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1513
1327
b29eefad2111 website - improve docs
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parents: 1326
diff changeset
1514 <h4 heading><a name="fn_def" href="#fn_def">Function Definitions</a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1515
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1516 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1517 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
1518
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1519 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1520 functiondef ::= <b>function</b> funcbody
1092
a26fbde7ee28 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 1090
diff changeset
1521 funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block end_function
a26fbde7ee28 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 1090
diff changeset
1522 end_function ::= <b>end_function</b> | <b>end</b>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1523 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1525 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1526 The following syntactic sugar simplifies function definitions:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1527
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1528 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1529 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
1530 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
1531 funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1532 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1533
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1534 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1535 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1536
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1537 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1538 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1539 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1540
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
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 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
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
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parents: 556
diff changeset
1545 f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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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 The statement
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 function t.a.b.c.f () <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 translates to
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
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1559 t.a.b.c.f = function () <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
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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 The statement
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
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parents: 556
diff changeset
1566 local function f () <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
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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 translates to
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>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1573 local f; f = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1574 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1575
a40e99cf0b0b work on manual
Franklin Schmidt <fschmidt@gmail.com>
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 not 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
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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 = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1581 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1582
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1583 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1584 (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
1585 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
1586
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1587
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1588 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1589 A function definition is an executable expression,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1590 whose value has type <em>function</em>.
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1591 When Luan precompiles a chunk,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1592 all its function bodies are precompiled too.
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1593 Then, whenever Luan executes the function definition,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1594 the function is <em>instantiated</em> (or <em>closed</em>).
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1595 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
1596 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
1597
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1598
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1599 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1600 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
1601 initialized with the argument values:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1602
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1603 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1604 parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1605 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1606
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1607 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1608 When a function is called,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1609 the list of arguments is adjusted to
1090
616761e0b9f6 update documentation for last change
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parents: 799
diff changeset
1610 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
1611 unless the function is a <em>vararg function</em>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1612 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
1613 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
1614 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
1615 instead, it collects all extra arguments and supplies them
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1616 to the function through a <em>vararg expression</em>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1617 which is also written as three dots.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1618 The value of this expression is a list of all actual extra arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1619 similar to a function with multiple results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1620 If a vararg expression is used inside another expression
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1621 or in the middle of a list of expressions,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1622 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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parents:
diff changeset
1623 If the expression is used as the last element of a list of expressions,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1624 then no adjustment is made
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1625 (unless that last expression is enclosed in parentheses).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1626
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1627
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1628 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1629 As an example, consider the following definitions:
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parents:
diff changeset
1630
562
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diff changeset
1631 <pre>
371
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diff changeset
1632 function f(a, b) end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1633 function g(a, b, ...) end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1634 function r() return 1,2,3 end
562
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diff changeset
1635 </pre>
417
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diff changeset
1636
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diff changeset
1637 <p>
371
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diff changeset
1638 Then, we have the following mapping from arguments to parameters and
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parents:
diff changeset
1639 to the vararg expression:
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parents:
diff changeset
1640
562
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diff changeset
1641 <pre>
371
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diff changeset
1642 CALL PARAMETERS
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parents:
diff changeset
1643
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diff changeset
1644 f(3) a=3, b=nil
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parents:
diff changeset
1645 f(3, 4) a=3, b=4
1090
616761e0b9f6 update documentation for last change
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parents: 799
diff changeset
1646 f(3, 4, 5) runtime error
616761e0b9f6 update documentation for last change
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parents: 799
diff changeset
1647 f(r(), 10) runtime error
616761e0b9f6 update documentation for last change
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parents: 799
diff changeset
1648 f(r()) runtime error
371
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diff changeset
1649
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diff changeset
1650 g(3) a=3, b=nil, ... --&gt; (nothing)
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parents:
diff changeset
1651 g(3, 4) a=3, b=4, ... --&gt; (nothing)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1652 g(3, 4, 5, 8) a=3, b=4, ... --&gt; 5 8
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1653 g(5, r()) a=5, b=1, ... --&gt; 2 3
562
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diff changeset
1654 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1655
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1656 <p>
464
eddf7c73373b fix references in the manual
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diff changeset
1657 Results are returned using the <b>return</b> statement (see <a href="#control">Control Structures</a>).
371
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diff changeset
1658 If control reaches the end of a function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1659 without encountering a <b>return</b> statement,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1660 then the function returns with no results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1661
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1662
1327
b29eefad2111 website - improve docs
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diff changeset
1663 <h3 heading><a name="visibility" href="#visibility">Visibility Rules</a></h3>
417
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diff changeset
1664
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diff changeset
1665 <p>
a40e99cf0b0b work on manual
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diff changeset
1666 Luan is a lexically scoped language.
371
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diff changeset
1667 The scope of a local variable begins at the first statement after
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parents:
diff changeset
1668 its declaration and lasts until the last non-void statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1669 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
1670 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1671
562
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diff changeset
1672 <pre>
371
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diff changeset
1673 x = 10 -- global variable
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1674 do -- new block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1675 local x = x -- new 'x', with value 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1676 print(x) --&gt; 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1677 x = x+1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1678 do -- another block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1679 local x = x+1 -- another 'x'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1680 print(x) --&gt; 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1681 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1682 print(x) --&gt; 11
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1683 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1684 print(x) --&gt; 10 (the global one)
562
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parents: 556
diff changeset
1685 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1686
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1687 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1688 Notice that, in a declaration like <code>local x = x</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1689 the new <code>x</code> being declared is not in scope yet,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1690 and so the second <code>x</code> refers to the outside variable.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1691
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1692
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1693 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1694 Because of the lexical scoping rules,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1695 local variables can be freely accessed by functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1696 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1697 A local variable used by an inner function is called
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1698 an <em>upvalue</em>, or <em>external local variable</em>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1699 inside the inner function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1700
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1701
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1702 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1703 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
1704 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1705 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1706
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1707 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1708 a = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1709 local x = 20
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1710 for i=1,10 do
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1711 local y = 0
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1712 a[i] = function () y=y+1; return x+y end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1713 end
562
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parents: 556
diff changeset
1714 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1715
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1716 <p>
371
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parents:
diff changeset
1717 The loop creates ten closures
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1718 (that is, ten instances of the anonymous function).
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1719 Each of these closures uses a different <code>y</code> variable,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1720 while all of them share the same <code>x</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1721
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1722
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
1723
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1724
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1725
1327
b29eefad2111 website - improve docs
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parents: 1326
diff changeset
1726 <h2 heading><a name="libs" href="#libs">Standard Libraries</a></h2>
468
9b51e2413cab documentation
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parents: 465
diff changeset
1727
9b51e2413cab documentation
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parents: 465
diff changeset
1728 <p>
9b51e2413cab documentation
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parents: 465
diff changeset
1729 The standard Luan libraries provide useful functions
9b51e2413cab documentation
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parents: 465
diff changeset
1730 that are implemented both in Java and in Luan itself.
9b51e2413cab documentation
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parents: 465
diff changeset
1731 How each function is implemented shouldn't matter to the user.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1732 Some of these functions provide essential services to the language
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1733 (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
1734 others provide access to "outside" services (e.g., I/O).
9b51e2413cab documentation
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parents: 465
diff changeset
1735
9b51e2413cab documentation
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parents: 465
diff changeset
1736
1327
b29eefad2111 website - improve docs
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parents: 1326
diff changeset
1737 <h3 heading><a name="default_lib" href="#default_lib">Default Environment</a></h3>
468
9b51e2413cab documentation
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parents: 465
diff changeset
1738
9b51e2413cab documentation
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parents: 465
diff changeset
1739 <p>
1353
8d95711f6615 replace java() with require "java"
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parents: 1342
diff changeset
1740 This is provided by default as a local variable for any Luan code as described in <a href="#env">Environments</a>.
470
5627eb637eb4 documentation
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parents: 469
diff changeset
1741
5627eb637eb4 documentation
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parents: 469
diff changeset
1742
1327
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parents: 1326
diff changeset
1743 <h4 heading><a name="require" href="#require"><code>require (mod_uri)</code></a></h4>
470
5627eb637eb4 documentation
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parents: 469
diff changeset
1744
5627eb637eb4 documentation
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parents: 469
diff changeset
1745 <p>
5627eb637eb4 documentation
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parents: 469
diff changeset
1746 Example use:
5627eb637eb4 documentation
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parents: 469
diff changeset
1747
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1748 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
1749 local Table = require "luan:Table.luan"
562
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parents: 556
diff changeset
1750 </pre>
470
5627eb637eb4 documentation
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parents: 469
diff changeset
1751
5627eb637eb4 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 469
diff changeset
1752 <p>
5627eb637eb4 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 469
diff changeset
1753 Could be defined as:
5627eb637eb4 documentation
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parents: 469
diff changeset
1754
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1755 <pre>
470
5627eb637eb4 documentation
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parents: 469
diff changeset
1756 local function require(mod_name)
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
1757 return <a href="#Package.load">Package.load</a>(mod_name) or <a href="#Luan.error">Luan.error</a>("module '"..mod_name.."' not found")
470
5627eb637eb4 documentation
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parents: 469
diff changeset
1758 end
562
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parents: 556
diff changeset
1759 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1760
1353
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1761 <p>
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1762 A special case is:
8d95711f6615 replace java() with require "java"
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parents: 1342
diff changeset
1763
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1764 <pre>
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1765 require "java"
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1766 </pre>
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1767
8d95711f6615 replace java() with require "java"
Franklin Schmidt <fschmidt@gmail.com>
parents: 1342
diff changeset
1768 <p>
8d95711f6615 replace java() with require "java"
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parents: 1342
diff changeset
1769 This enables Java in the current chunk if that chunk has permission to use Java. If the chunk doesn't have permission to use Java, then an error is thrown.
8d95711f6615 replace java() with require "java"
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1770
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1771
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b29eefad2111 website - improve docs
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1772 <h3 heading><a name="luan_lib" href="#luan_lib">Basic Functions</a></h3>
470
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diff changeset
1773
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diff changeset
1774 <p>
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diff changeset
1775 Include this library by:
5627eb637eb4 documentation
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diff changeset
1776
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diff changeset
1777 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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diff changeset
1778 local Luan = require "luan:Luan.luan"
562
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diff changeset
1779 </pre>
470
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diff changeset
1780
476
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diff changeset
1781 <p>
470
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diff changeset
1782 The basic library provides basic functions to Luan that don't depend on other libaries.
5627eb637eb4 documentation
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diff changeset
1783
5627eb637eb4 documentation
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diff changeset
1784
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c4216a583de4 add links to functions in manual
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1785 <h4 heading><a name="Luan.do_file" href="#Luan.do_file"><code>Luan.do_file ([uri])</code></a></h4>
470
5627eb637eb4 documentation
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diff changeset
1786
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diff changeset
1787 <p>
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1788 Could be defined as:
5627eb637eb4 documentation
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diff changeset
1789
562
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1790 <pre>
470
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diff changeset
1791 function Luan.do_file(uri)
1316
11d3640e739d load_file returns nil for missing file
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1792 local fn = <a href="#Luan.load_file">Luan.load_file</a>(uri) or <a href="#Luan.error">Luan.error</a>("file '"..uri.."' not found")
11d3640e739d load_file returns nil for missing file
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1793 return fn()
470
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1794 end
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1795 </pre>
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diff changeset
1796
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diff changeset
1797
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diff changeset
1798
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1799 <h4 heading><a name="Luan.error" href="#Luan.error"><code>Luan.error (message)</code></a></h4>
470
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1800
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diff changeset
1801 <p>
482
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diff changeset
1802 Throws an error containing the message.
7e9fcfbf22ec documentation
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diff changeset
1803
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diff changeset
1804 <p>
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1805 Could be defined as:
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1806
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1807 <pre>
482
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1808 function Luan.error(message)
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diff changeset
1809 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
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1810 end
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1811 </pre>
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diff changeset
1812
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1813
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diff changeset
1814
695
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1815 <h4 heading><a name="Luan.eval" href="#Luan.eval"><code>Luan.eval (text [, source_name])</code></a></h4>
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diff changeset
1816
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diff changeset
1817 <p>
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diff changeset
1818 Evaluates <code>text</code> as a Luan expression.
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diff changeset
1819
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diff changeset
1820 <p>
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diff changeset
1821 Could be defined as:
5042e487d717 documentation
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diff changeset
1822
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diff changeset
1823 <pre>
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diff changeset
1824 function Luan.eval(text,source_name)
5042e487d717 documentation
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diff changeset
1825 return Luan.load( "return "..text, source_name or "eval" )()
5042e487d717 documentation
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1826 end
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diff changeset
1827 </pre>
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diff changeset
1828
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diff changeset
1829
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diff changeset
1830
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c4216a583de4 add links to functions in manual
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diff changeset
1831 <h4 heading><a name="Luan.get_metatable" href="#Luan.get_metatable"><code>Luan.get_metatable (table)</code></a></h4>
562
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1832
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diff changeset
1833 <p>
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diff changeset
1834 If <code>table</code> does not have a metatable, returns <b>nil</b>.
371
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1835 Otherwise,
562
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diff changeset
1836 if the table's metatable has a <code>"__metatable"</code> field,
371
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1837 returns the associated value.
470
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diff changeset
1838 Otherwise, returns the metatable of the given table.
371
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diff changeset
1839
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diff changeset
1840
1373
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diff changeset
1841 <h4 heading><a name="Luan.hash_code" href="#Luan.ipairs"><code>Luan.hash_code (v)</code></a></h4>
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diff changeset
1842
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diff changeset
1843 <p>
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diff changeset
1844 Returns the hash code of <code>v</code>.
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diff changeset
1845
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diff changeset
1846
642
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diff changeset
1847 <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
1848
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diff changeset
1849 <p>
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diff changeset
1850 Returns an iterator function
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1851 so that the construction
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1852
562
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diff changeset
1853 <pre>
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diff changeset
1854 for i,v in ipairs(t) do <em>body</em> end
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diff changeset
1855 </pre>
474
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diff changeset
1856
00646edc9d92 documentation
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diff changeset
1857 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1858 will iterate over the key&ndash;value pairs
562
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diff changeset
1859 (<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
1860 up to the first nil value.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1861
474
00646edc9d92 documentation
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parents: 472
diff changeset
1862 <p>
00646edc9d92 documentation
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parents: 472
diff changeset
1863 Could be defined as:
00646edc9d92 documentation
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parents: 472
diff changeset
1864
562
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diff changeset
1865 <pre>
474
00646edc9d92 documentation
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parents: 472
diff changeset
1866 function Luan.ipairs(t)
00646edc9d92 documentation
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parents: 472
diff changeset
1867 local i = 0
00646edc9d92 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 472
diff changeset
1868 return function()
00646edc9d92 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 472
diff changeset
1869 if i < #t then
00646edc9d92 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 472
diff changeset
1870 i = i + 1
00646edc9d92 documentation
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parents: 472
diff changeset
1871 return i, t[i]
00646edc9d92 documentation
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diff changeset
1872 end
00646edc9d92 documentation
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diff changeset
1873 end
00646edc9d92 documentation
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diff changeset
1874 end
562
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diff changeset
1875 </pre>
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parents: 556
diff changeset
1876
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parents: 556
diff changeset
1877
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diff changeset
1878
695
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diff changeset
1879 <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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parents:
diff changeset
1880
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1881 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1882 Loads a chunk.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1883
474
00646edc9d92 documentation
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diff changeset
1884 <p>
562
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diff changeset
1885 The <code>text</code> is compiled.
371
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parents:
diff changeset
1886 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
1887 returns the compiled chunk as a function;
474
00646edc9d92 documentation
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parents: 472
diff changeset
1888 otherwise, throws an error.
00646edc9d92 documentation
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parents: 472
diff changeset
1889
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diff changeset
1890 <p>
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diff changeset
1891 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
1892
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diff changeset
1893 <p>
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diff changeset
1894 If the <code>env</code> parameter is supplied, it becomes the <code>_ENV</code> of the chunk.
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diff changeset
1895
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diff changeset
1896
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
1897 <h4 heading><a name="Luan.load_file" href="#Luan.load_file"><code>Luan.load_file ([file_uri])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1898
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diff changeset
1899 <p>
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diff changeset
1900 Similar to <a href="#Luan.load"><code>load</code></a>,
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1901 but gets the chunk from file <code>file_uri</code>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1902 or from the standard input,
474
00646edc9d92 documentation
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parents: 472
diff changeset
1903 if no file uri is given.
00646edc9d92 documentation
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parents: 472
diff changeset
1904
00646edc9d92 documentation
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parents: 472
diff changeset
1905 <p>
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diff changeset
1906 Could be defined as:
00646edc9d92 documentation
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diff changeset
1907
562
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diff changeset
1908 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
1909 function Luan.load_file(file_uri)
474
00646edc9d92 documentation
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diff changeset
1910 file_uri = file_uri or "stdin:"
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
1911 local f = Io.uri(file_uri)
1316
11d3640e739d load_file returns nil for missing file
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diff changeset
1912 if not f.exists() then
11d3640e739d load_file returns nil for missing file
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diff changeset
1913 return nil
11d3640e739d load_file returns nil for missing file
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diff changeset
1914 end
474
00646edc9d92 documentation
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diff changeset
1915 return <a href="#Luan.load">Luan.load</a>( f.read_text(), file_uri )
00646edc9d92 documentation
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diff changeset
1916 end
562
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diff changeset
1917 </pre>
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diff changeset
1918
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diff changeset
1919
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diff changeset
1920 <h4 heading><a name="Luan.new_error" href="#Luan.new_error"><code>Luan.new_error (message)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1921
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diff changeset
1922 <p>
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diff changeset
1923 Creates a new error table containing the message assigned to "<code>message</code>". The error table also contains a <code>throw</code> function which throws the error. The table also contains a list of stack trace elements where each stack trace element is a table containing "<code>source</code>", "<code>line</code>", and possible "<code>call_to</code>". The table also has a metatable containing "<code>__to_string</code>" to render the error.
482
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diff changeset
1924
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diff changeset
1925 <p>
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diff changeset
1926 To print the current stack trace, you could do:
7e9fcfbf22ec documentation
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diff changeset
1927
562
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diff changeset
1928 <pre>
482
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diff changeset
1929 Io.print( Luan.new_error "stack" )
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1930 </pre>
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1931
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1932
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1933 <h4 heading><a name="Luan.pairs" href="#Luan.pairs"><code>Luan.pairs (t)</code></a></h4>
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1934
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1935 <p>
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1936 If <code>t</code> has a metamethod <code>__pairs</code>,
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1937 calls it with <code>t</code> as argument and returns the
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1938 result from the call.
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1939
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1940
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1941 <p>
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1942 Otherwise,
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1943 returns a function
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1944 so that the construction
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1945
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1946 <pre>
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1947 for k,v in pairs(t) do <em>body</em> end
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1948 </pre>
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1949
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1950 <p>
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diff changeset
1951 will iterate over all key&ndash;value pairs of table <code>t</code>.
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1952
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1953
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1954
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1955 <h4 heading><a name="Luan.pcall" href="#Luan.pcall"><code>Luan.pcall (f [, arg1, &middot;&middot;&middot;])</code></a></h4>
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1956
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1957 <p>
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1958 Calls function <code>f</code> with
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1959 the given arguments in <em>protected mode</em>.
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1960 This means that any error inside&nbsp;<code>f</code> is not propagated;
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1961 instead, <code>pcall</code> catches the error
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1962 and returns a status code.
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1963 Its first result is the status code (a boolean),
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1964 which is true if the call succeeds without errors.
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1965 In such case, <code>pcall</code> also returns all results from the call,
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1966 after this first result.
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1967 In case of any error, <code>pcall</code> returns <b>false</b> plus the error.
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1968
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1969
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1970
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1971
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1972 <p>
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1973 <hr><h3><a name="pdf-print"><code>print (&middot;&middot;&middot;)</code></a></h3>
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1974 Receives any number of arguments
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1975 and prints their values to <code>stdout</code>,
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1976 using the <a href="#pdf-tostring"><code>tostring</code></a> function to convert each argument to a string.
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1977 <code>print</code> is not intended for formatted output,
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1978 but only as a quick way to show a value,
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1979 for instance for debugging.
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parents:
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1980 For complete control over the output,
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parents:
diff changeset
1981 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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1982
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parents:
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1983
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parents:
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1984
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1985 <h4 heading><a name="Luan.range" href="#Luan.range"><code>Luan.range (start, stop [, step])</code></a></h4>
476
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diff changeset
1986
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diff changeset
1987 <p>
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diff changeset
1988 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.
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diff changeset
1989
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diff changeset
1990 <p>
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diff changeset
1991 Example use:
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diff changeset
1992
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1993 <pre>
476
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1994 for i in range(1,10) do
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diff changeset
1995 Io.print("count up:",i)
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1996 end
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1997 for i in range(10,0,-1) do
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diff changeset
1998 Io.print("count down:",i)
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1999 end
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2000 </pre>
476
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diff changeset
2001
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diff changeset
2002 <p>
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diff changeset
2003 Could be defined as:
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diff changeset
2004
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diff changeset
2005 <pre>
476
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diff changeset
2006 function Luan.range(start, stop, step)
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diff changeset
2007 step = step or 1
478
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diff changeset
2008 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
2009 local i = start
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diff changeset
2010 return function()
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diff changeset
2011 if step > 0 and i <= stop or step < 0 and i >= stop then
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diff changeset
2012 local rtn = i
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diff changeset
2013 i = i + step
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diff changeset
2014 return rtn
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2015 end
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2016 end
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2017 end
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diff changeset
2018 </pre>
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2019
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2020
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diff changeset
2021
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diff changeset
2022 <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
2023
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diff changeset
2024 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2025 Checks whether <code>v1</code> is equal to <code>v2</code>,
371
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parents:
diff changeset
2026 without invoking any metamethod.
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parents:
diff changeset
2027 Returns a boolean.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2029
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parents:
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2030
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diff changeset
2031 <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
2032
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diff changeset
2033 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2034 Gets the real value of <code>table[index]</code>,
371
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parents:
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2035 without invoking any metamethod.
562
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diff changeset
2036 <code>table</code> must be a table;
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diff changeset
2037 <code>index</code> may be any value.
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parents: 556
diff changeset
2038
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2039
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2040
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diff changeset
2041 <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
2042
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diff changeset
2043 <p>
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diff changeset
2044 Returns the length of the object <code>v</code>,
371
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parents:
diff changeset
2045 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
2046 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2047 Returns an integer.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2048
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2049
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2050
642
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diff changeset
2051 <h4 heading><a name="Luan.raw_set" href="#Luan.raw_set"><code>Luan.raw_set (table, index, value)</code></a></h4>
562
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diff changeset
2052
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2053 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2054 Sets the real value of <code>table[index]</code> to <code>value</code>,
371
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parents:
diff changeset
2055 without invoking any metamethod.
562
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diff changeset
2056 <code>table</code> must be a table,
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diff changeset
2057 <code>index</code> any value different from <b>nil</b>,
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diff changeset
2058 and <code>value</code> any Lua value.
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diff changeset
2059
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2060
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diff changeset
2061 <h4 heading><a name="Luan.set_metatable" href="#Luan.set_metatable"><code>Luan.set_metatable (table, metatable)</code></a></h4>
371
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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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2064 Sets the metatable for the given table.
562
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diff changeset
2065 If <code>metatable</code> is <b>nil</b>,
371
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parents:
diff changeset
2066 removes the metatable of the given table.
562
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diff changeset
2067 If the original metatable has a <code>"__metatable"</code> field,
371
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parents:
diff changeset
2068 raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2069
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2070
1189
73d754b1889f add stringify
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parents: 1164
diff changeset
2071 <h4 heading><a name="Luan.stringify" href="#Luan.stringify"><code>Luan.stringify (v [,strict])</code></a></h4>
73d754b1889f add stringify
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parents: 1164
diff changeset
2072
73d754b1889f add stringify
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parents: 1164
diff changeset
2073 <p>
1303
693da73c8a2f update documentation
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parents: 1277
diff changeset
2074 Receives a value of any type and converts it to a string that is a Luan expression. <code>strict</code> is a string. If <code>strict</code> is 'strict' then invalid types throw an error. If <code>strict</code> is nil then invalid types are represented but the resulting expression is invalid. <code>strict</code> defaults to <b>nil</b>.
1189
73d754b1889f add stringify
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parents: 1164
diff changeset
2075
371
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parents:
diff changeset
2076
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parents: 629
diff changeset
2077 <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
2078
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diff changeset
2079 <p>
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e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2080 Receives a value of any type and
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2081 converts it to a string in a human-readable format.
475
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diff changeset
2082
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diff changeset
2083 <p>
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2084 If the metatable of <code>v</code> has a <code>"__to_string"</code> field,
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2085 then <code>to_string</code> calls the corresponding value
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2086 with <code>v</code> as argument,
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2087 and uses the result of the call as its result.
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2088
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2089
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2090
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2091 <h4 heading><a name="Luan.try" href="#Luan.try"><code>Luan.try (t, &middot;&middot;&middot;)</code></a></h4>
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2092
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2093 <p>
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diff changeset
2094 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.
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diff changeset
2095
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diff changeset
2096 <p>
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diff changeset
2097 Example use:
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diff changeset
2098
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2099 <pre>
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2100 try {
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diff changeset
2101 function()
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2102 a_dangerous_fn()
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2103 end
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diff changeset
2104 catch = function(e)
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diff changeset
2105 -- handle error
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2106 end
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diff changeset
2107 finally = function()
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diff changeset
2108 -- clean up
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2109 end
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2110 }
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2111 </pre>
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diff changeset
2112
482
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diff changeset
2113 <p>
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diff changeset
2114 Could be defined as:
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diff changeset
2115
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2116 <pre>
482
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2117 function Luan.try(t)
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diff changeset
2118 local r = { <a href="#Luan.pcall">Luan.pcall</a>(t[1]) }
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2119 if r[1] then
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diff changeset
2120 Table.remove(r,1)
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diff changeset
2121 elseif t.catch ~= nil then
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diff changeset
2122 r = { t.catch(r[2]) }
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diff changeset
2123 else
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diff changeset
2124 t.finally and t.finally()
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diff changeset
2125 r[2].throw()
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diff changeset
2126 end
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diff changeset
2127 t.finally and t.finally()
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diff changeset
2128 return Table.unpack(r)
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diff changeset
2129 end
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2130 </pre>
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diff changeset
2131
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diff changeset
2132
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2133 <h4 heading><a name="Luan.type" href="#Luan.type"><code>Luan.type (v)</code></a></h4>
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diff changeset
2134
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diff changeset
2135 <p>
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2136 Returns the type of its only argument, coded as a string.
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2137 The possible results of this function are
562
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2138 "<code>nil</code>" (a string, not the value <b>nil</b>),
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diff changeset
2139 "<code>number</code>",
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diff changeset
2140 "<code>string</code>",
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diff changeset
2141 "<code>binary</code>",
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diff changeset
2142 "<code>boolean</code>",
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diff changeset
2143 "<code>table</code>",
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diff changeset
2144 "<code>function</code>",
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diff changeset
2145 and "<code>java</code>".
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diff changeset
2146
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diff changeset
2147
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2148 <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
2149
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diff changeset
2150 <p>
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diff changeset
2151 Returns a function so that the construction
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diff changeset
2152
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2153 <pre>
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623dfe0e2e73 change Luan.values
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2154 for i, v in Luan.values(&middot;&middot;&middot;) do <em>body</em> end
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diff changeset
2155 </pre>
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diff changeset
2156
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diff changeset
2157 <p>
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diff changeset
2158 will iterate over all values of <code>&middot;&middot;&middot;</code>.
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diff changeset
2159
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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.VERSION" href="#Luan.VERSION"><code>Luan.VERSION</code></a></h4>
475
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diff changeset
2163
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diff changeset
2164 <p>
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diff changeset
2165 A global variable (not a function) that
1325
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diff changeset
2166 holds a string containing the current Luan version.
562
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diff changeset
2167
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diff changeset
2168
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diff changeset
2169
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diff changeset
2170
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diff changeset
2171
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diff changeset
2172
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diff changeset
2173 <h3 heading><a name="package_lib" href="#package_lib">Modules</a></h3>
476
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diff changeset
2174
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parents: 475
diff changeset
2175 <p>
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diff changeset
2176 Include this library by:
cd22e4694ea3 documentation
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diff changeset
2177
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diff changeset
2178 <pre>
693
ca169567ce07 module URIs must now include ".luan"
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parents: 685
diff changeset
2179 local Package = require "luan:Package.luan"
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diff changeset
2180 </pre>
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diff changeset
2181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2182 <p>
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parents:
diff changeset
2183 The package library provides basic
476
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diff changeset
2184 facilities for loading modules in Luan.
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diff changeset
2185
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diff changeset
2186
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diff changeset
2187 <h4 heading><a name="Package.load" href="#Package.load"><code>Package.load (mod_uri)</code></a></h4>
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parents:
diff changeset
2188
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2189 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2190 Loads the given module.
562
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diff changeset
2191 The function starts by looking into the <a href="#Package.loaded"><code>Package.loaded</code></a> table
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diff changeset
2192 to determine whether <code>mod_uri</code> is already loaded.
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diff changeset
2193 If it is, then <code>Package.load</code> returns the value stored
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diff changeset
2194 at <code>Package.loaded[mod_uri]</code>.
476
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diff changeset
2195 Otherwise, it tries to load a new value for the module.
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diff changeset
2196
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diff changeset
2197 <p>
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diff changeset
2198 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
2199
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diff changeset
2200 <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
2201 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.
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diff changeset
2202
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diff changeset
2203 <p>
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diff changeset
2204 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
2205
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diff changeset
2206
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2207
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diff changeset
2208
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diff changeset
2209 <h4 heading><a name="Package.loaded" href="#Package.loaded"><code>Package.loaded</code></a></h4>
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diff changeset
2210
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diff changeset
2211
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diff changeset
2212 <p>
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diff changeset
2213 A table used by <a href="#Package.load"><code>Package.load</code></a> to control which
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diff changeset
2214 modules are already loaded.
562
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diff changeset
2215 When you load a module <code>mod_uri</code> and
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diff changeset
2216 <code>Package.loaded[mod_uri]</code> is not <b>nil</b>,
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diff changeset
2217 <a href="#Package.load"><code>Package.load</code></a> simply returns the value stored there.
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diff changeset
2218
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2220 <p>
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diff changeset
2221 This variable is only a reference to the real table;
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diff changeset
2222 assignments to this variable do not change the
562
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diff changeset
2223 table used by <a href="#Package.load"><code>Package.load</code></a>.
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diff changeset
2224
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2225
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2226
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2227
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2228
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diff changeset
2229
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diff changeset
2230 <h3 heading><a name="string_lib" href="#string_lib">String Manipulation</a></h3>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2231
e25ba7a2e816 some String documentation and fixes
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diff changeset
2232 <p>
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2233 Include this library by:
e25ba7a2e816 some String documentation and fixes
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diff changeset
2234
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2235 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2236 local String = require "luan:String.luan"
562
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diff changeset
2237 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2238
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2239 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2240 This library provides generic functions for string manipulation,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2241 such as finding and extracting substrings, and pattern matching.
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2242 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
2243 (not at&nbsp;0, as in Java).
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2244 Indices are allowed to be negative and are interpreted as indexing backwards,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2245 from the end of the string.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2246 Thus, the last character is at position -1, and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2247
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2248
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2249
642
c4216a583de4 add links to functions in manual
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diff changeset
2250 <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
2251
e25ba7a2e816 some String documentation and fixes
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diff changeset
2252 <p>
371
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diff changeset
2253 Receives zero or more integers.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2254 Returns a string with length equal to the number of arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2255 in which each character has the internal numerical code equal
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2256 to its corresponding argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2258
642
c4216a583de4 add links to functions in manual
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diff changeset
2259 <h4 heading><a name="String.encode" href="#String.encode"><code>String.encode (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2260
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diff changeset
2261 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2262 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
2263
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diff changeset
2264
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2265
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2266
642
c4216a583de4 add links to functions in manual
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diff changeset
2267 <h4 heading><a name="String.find" href="#String.find"><code>String.find (s, pattern [, init [, plain]])</code></a></h4>
371
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parents:
diff changeset
2268
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parents:
diff changeset
2269 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2270 Looks for the first match of
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2271 <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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diff changeset
2272 If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2273 where this occurrence starts and ends;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2274 otherwise, it returns <b>nil</b>.
562
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diff changeset
2275 A third, optional numerical argument <code>init</code> specifies
371
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diff changeset
2276 where to start the search;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2277 its default value is&nbsp;1 and can be negative.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2278 A value of <b>true</b> as a fourth, optional argument <code>plain</code>
371
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diff changeset
2279 turns off the pattern matching facilities,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2280 so the function does a plain "find substring" operation,
562
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diff changeset
2281 with no characters in <code>pattern</code> being considered magic.
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2282 Note that if <code>plain</code> is given, then <code>init</code> must be given as well.
371
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diff changeset
2283
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parents:
diff changeset
2284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2285 If the pattern has captures,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2286 then in a successful match
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2287 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
2288 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2289
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2290
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2291
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2292
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2293 <h4 heading><a name="String.format" href="#String.format"><code>String.format (formatstring, &middot;&middot;&middot;)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2294
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2295
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2296 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2297 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
2298 following the description given in its first argument (which must be a string).
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2299 The format string follows the same rules as the Java function <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#format(java.lang.String,%20java.lang.Object...)"><code>String.format</code></a> because Luan calls this internally.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2300
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diff changeset
2301 <p>
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diff changeset
2302 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
2303
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2304
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2305
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2306 <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
2307
e25ba7a2e816 some String documentation and fixes
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diff changeset
2308 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2309 Returns an iterator function that,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2310 each time it is called,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2311 returns the next captures from <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>)
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2312 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2313 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
2314 then the whole match is produced in each call.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2317 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2318 As an example, the following loop
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2319 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
2320 printing one per line:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2321
562
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parents: 556
diff changeset
2322 <pre>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2323 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2324 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
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diff changeset
2325 print(w)
e25ba7a2e816 some String documentation and fixes
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diff changeset
2326 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2327 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2328
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2329 <p>
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parents: 556
diff changeset
2330 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
2331 given string into a table:
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parents:
diff changeset
2332
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2333 <pre>
555
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2334 local t = {}
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2335 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2336 for k, v in String.gmatch(s, [[(\w+)=(\w+)]]) do
e25ba7a2e816 some String documentation and fixes
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diff changeset
2337 t[k] = v
e25ba7a2e816 some String documentation and fixes
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diff changeset
2338 end
562
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diff changeset
2339 </pre>
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parents: 556
diff changeset
2340
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2341 <p>
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diff changeset
2342 For this function, a caret '<code>^</code>' at the start of a pattern does not
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2343 work as an anchor, as this would prevent the iteration.
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parents:
diff changeset
2344
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2345
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2346
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2347 <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
2348
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diff changeset
2349 <p>
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diff changeset
2350 Returns a copy of <code>s</code>
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diff changeset
2351 in which all (or the first <code>n</code>, if given)
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2352 occurrences of the <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) have been
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2353 replaced by a replacement string specified by <code>repl</code>,
371
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parents:
diff changeset
2354 which can be a string, a table, or a function.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2355 <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
2356 the total number of matches that occurred.
562
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diff changeset
2357 The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
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diff changeset
2358
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parents: 556
diff changeset
2359
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diff changeset
2360 <p>
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diff changeset
2361 If <code>repl</code> is a string, then its value is used for replacement.
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diff changeset
2362 The character&nbsp;<code>\</code> works as an escape character.
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diff changeset
2363 Any sequence in <code>repl</code> of the form <code>$<em>d</em></code>,
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diff changeset
2364 with <em>d</em> between 1 and 9,
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diff changeset
2365 stands for the value of the <em>d</em>-th captured substring.
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2366 The sequence <code>$0</code> stands for the whole match.
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diff changeset
2367
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2368
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diff changeset
2369 <p>
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diff changeset
2370 If <code>repl</code> is a table, then the table is queried for every match,
371
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parents:
diff changeset
2371 using the first capture as the key.
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parents:
diff changeset
2372
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2373
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2374 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2375 If <code>repl</code> is a function, then this function is called every time a
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2376 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
2377 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2378
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2379
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2380 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2381 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2382 if the pattern specifies no captures,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2383 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
2384
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2385
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2386 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2387 If the value returned by the table query or by the function call
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2388 is not <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2389 then it is used as the replacement string;
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2390 otherwise, if it is <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2391 then there is no replacement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2392 (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
2393
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2396 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2397
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2398 <pre>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2399 x = String.gsub("hello world", [[(\w+)]], "$1 $1")
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2400 --&gt; x="hello hello world world"
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2401
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2402 x = String.gsub("hello world", [[\w+]], "$0 $0", 1)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2403 --&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
2404
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2405 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
2406 --&gt; x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2407
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2408 x = String.gsub("4+5 = $return 4+5$", [[\$(.*?)\$]], function (s)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2409 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2410 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2411 --&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
2412
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2413 local t = {name="lua", version="5.3"}
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2414 x = String.gsub("$name-$version.tar.gz", [[\$(\w+)]], t)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2415 --&gt; x="lua-5.3.tar.gz"
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2416 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2417
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2418
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2419
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2420 <h4 heading><a name="String.literal" href="#String.literal"><code>String.literal (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2421 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2422 Returns a string which matches the literal string <code>s</code> in a regular expression. This function is simply the Java method <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html#quote(java.lang.String)"><code>Pattern.quote</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2423
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2424
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2425 <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
2426 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2427 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
2428 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
2429 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
2430
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2431
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2432
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2433
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2434 <h4 heading><a name="String.match" href="#String.match"><code>String.match (s, pattern [, init])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2435
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2436 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2437 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2438 <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
2439 If it finds one, then <code>match</code> returns
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2440 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
2441 otherwise it returns <b>nil</b>.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2442 If <code>pattern</code> specifies no captures,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2443 then the whole match is returned.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2444 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
2445 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
2446 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
2447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2448
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2449 <h4 heading><a name="String.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
2450 <p>
629
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2451 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
2452 This function is equivalent to
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2453
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2454 <pre>
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2455 return String.match(s,pattern) ~= nil
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2456 </pre>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2457
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2458
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2459 <h4 heading><a name="String.rep" href="#String.rep"><code>String.rep (s, n [, sep])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2460 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2461 Returns a string that is the concatenation of <code>n</code> copies of
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2462 the string <code>s</code> separated by the string <code>sep</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2463 The default value for <code>sep</code> is the empty string
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2464 (that is, no separator).
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2465 Returns the empty string if <code>n</code> is not positive.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2466
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2467
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2468
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2469
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2470 <h4 heading><a name="String.reverse" href="#String.reverse"><code>String.reverse (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2471 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2472 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
2473
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2474
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2475
1195
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2476 <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
2477
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2478 <p>
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2479 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
2480
9a57f0b16c2b better String.split
Franklin Schmidt <fschmidt@gmail.com>
parents: 1189
diff changeset
2481
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2482
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2483 <h4 heading><a name="String.sub" href="#String.sub"><code>String.sub (s, i [, j])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2484
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2485 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2486 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2487 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
2488 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2489 If <code>j</code> is absent, then it is assumed to be equal to -1
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2490 (which is the same as the string length).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2491 In particular,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2492 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
2493 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2494 and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2495 with length <code>i</code>.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2497
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2498 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2499 If, after the translation of negative indices,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2500 <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
2501 it is corrected to 1.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2502 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
2503 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
2504 If, after these corrections,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2505 <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
2506 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
2507
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2509
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2510 <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
2511
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2512 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2513 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
2514
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2515
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2516
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2517 <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
2518
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2519 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2520 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2521 <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
2522 If the argument is
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2523 a string convertible to a number,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2524 then <code>to_number</code> returns this number;
556
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2525 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2526
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2527 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2528
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2529
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2530 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2531 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2532 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
2533 an integer numeral in that base.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2534 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
2535 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
2536 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2537 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
2538 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2539
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2540
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2541
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2542 <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
2543
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2544 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2545 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
2546
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2547
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2548
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2549
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2550 <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
2551
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2552 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2553 Returns 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
2554 <code>s[i+1]</code>, ..., <code>s[j]</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2555 The default value for <code>i</code> is&nbsp;1;
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2556 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
2557 These indices are corrected
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2558 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
2559
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2560
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2561
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
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.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
2565 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2566 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
2567 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
2568 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
2569 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
2570
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2571
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2572
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2573
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2574
1327
b29eefad2111 website - improve docs
Franklin Schmidt <fschmidt@gmail.com>
parents: 1326
diff changeset
2575 <h3 heading><a name="binary_lib" href="#binary_lib">Binary Manipulation</a></h3>
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2576
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2577 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2578 Include this library by:
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2579
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2580 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2581 local Binary = require "luan:Binary.luan"
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2582 </pre>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2583
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2584
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2585 <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
2586
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2587 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2588 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2589 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2590 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2591 to its corresponding argument.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2592
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2593
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2594 <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
2595
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2596 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2597 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2598 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2599 The default value for <code>i</code> is&nbsp;1;
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2600 the default value for <code>j</code> is&nbsp;<code>i</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2601 These indices are corrected
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2602 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
2603
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2604
1257
e38f5869e9df don't reset in send_redirect and other improvements
Franklin Schmidt <fschmidt@gmail.com>
parents: 1216
diff changeset
2605 <h4 heading><a name="Binary.to_string" href="#Binary.to_string"><code>Binary.to_string (b [,charset])</code></a></h4>
e38f5869e9df don't reset in send_redirect and other improvements
Franklin Schmidt <fschmidt@gmail.com>
parents: 1216
diff changeset
2606 <p>
e38f5869e9df don't reset in send_redirect and other improvements
Franklin Schmidt <fschmidt@gmail.com>
parents: 1216
diff changeset
2607 If <code>charset</code> is not nil then converts the binary <code>b</code> to a string using the Java <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#String(byte[],%20java.lang.String)">String constructor</a>, else makes each byte a char.
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2608
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2609
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2610
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2611
1327
b29eefad2111 website - improve docs
Franklin Schmidt <fschmidt@gmail.com>
parents: 1326
diff changeset
2612 <h3 heading><a name="table_lib" href="#table_lib">Table Manipulation</a></h3>
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2613
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2614 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2615 Include this library by:
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2616
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2617 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2618 local Table = require "luan:Table.luan"
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2619 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2620
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2621 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2622 This library provides generic functions for table manipulation.
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2623 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2624
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2625
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
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="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
2628
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2629 <p>
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2630 Clears the table.
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2631
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2632
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2633 <h4 heading><a name="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
2634
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2635 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2636 Given a list,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2637 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
2638 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
2639 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
2640 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
2641 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
2642
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2643
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2644 <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
2645
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2646 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2647 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
2648 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
2649 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2650
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2651
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2652
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2653 <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
2654
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2655 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2656 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
2657 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2658 <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
2659
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2660
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2661
1100
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2662 <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
2663
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2664
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
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.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
2667
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2668 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2669 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
2670 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
2671 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
2672
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2673
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2674
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2675
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2676 <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
2677
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2678
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2679 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2680 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
2681 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
2682 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
2683 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
2684 <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
2685 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
2686 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
2687 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
2688 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
2689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2690
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2691
1100
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2692 <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
2693
ad6b3b9fef40 add Table.is_empty() and Table.size()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1092
diff changeset
2694
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2695
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2696 <h4 heading><a name="Table.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
2697
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2698 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2699 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
2700 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
2701 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
2702 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
2703 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
2704 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
2705 (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
2706 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
2707 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
2708
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2709 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2710 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
2711 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
2712 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
2713
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2714
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2715
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2716 <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
2717
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2718 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2719 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
2720 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
2721
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2722 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2723 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
2724 </pre>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2725
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2726 <p>
1277
5ba660381bd5 fix Io.print()
Franklin Schmidt <fschmidt@gmail.com>
parents: 1276
diff changeset
2727 By default, <code>i</code> is 1 and <code>j</code> is <code>list.n or #list</code>.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2728
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2729
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2730
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2731
1327
b29eefad2111 website - improve docs
Franklin Schmidt <fschmidt@gmail.com>
parents: 1326
diff changeset
2732 <h3 heading><a name="number_lib" href="#number_lib">Number Manipulation</a></h3>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2733
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2734 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2735 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2736
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2737 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2738 local Number = require "luan:Number.luan"
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2739 </pre>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2740
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2741
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2742 <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
2743 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2744 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2745
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2746
1342
60599adc27b8 add lucene search options
Franklin Schmidt <fschmidt@gmail.com>
parents: 1327
diff changeset
2747 <h4 heading><a name="Number.float" href="#Number.double"><code>Number.float (x)</code></a></h4>
60599adc27b8 add lucene search options
Franklin Schmidt <fschmidt@gmail.com>
parents: 1327
diff changeset
2748 <p>
60599adc27b8 add lucene search options
Franklin Schmidt <fschmidt@gmail.com>
parents: 1327
diff changeset
2749 Returns <code>x</code> as a float.
60599adc27b8 add lucene search options
Franklin Schmidt <fschmidt@gmail.com>
parents: 1327
diff changeset
2750
60599adc27b8 add lucene search options
Franklin Schmidt <fschmidt@gmail.com>
parents: 1327
diff changeset
2751
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2752 <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
2753 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2754 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
2755 returns that integer.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2756 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2757
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2758
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2759 <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
2760 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2761 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
2762 returns that long.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2763 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2764
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2765
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2766 <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
2767 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2768 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
2769
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2770
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2771 <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
2772 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2773 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
2774
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2775
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2776
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2777
1327
b29eefad2111 website - improve docs
Franklin Schmidt <fschmidt@gmail.com>
parents: 1326
diff changeset
2778 <h3 heading><a name="math_lib" href="#math_lib">Mathematical Functions</a></h3>
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2779
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2780 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2781 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2782
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2783 <pre>
693
ca169567ce07 module URIs must now include ".luan"
Franklin Schmidt <fschmidt@gmail.com>
parents: 685
diff changeset
2784 local Math = require "luan:Math.luan"
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2785 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2786
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2787 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2788 This library provides basic mathematical functions.
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2789 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
2790
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2791
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2792 <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
2793
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2794 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2795 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
2796
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2797
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2798
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2799 <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
2800
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2801 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2802 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
2803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2804
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2805
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2806
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2807 <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
2808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2809 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2810 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
2811
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2812
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2813
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2814
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2815 <h4 heading><a name="Math.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
2816
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2817 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2818 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
2819 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
2820 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2821 (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
2822
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2823
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2824
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2825
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2826 <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
2827
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2828 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2829 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
2830
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2831
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2832
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2833
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2834 <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
2835
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2836 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2837 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
2838
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2839
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2840
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2841
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2842 <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
2843
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2844 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2845 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
2846
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2847
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2848
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2849
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2850 <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
2851
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2852 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2853 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
2854 (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
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.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
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 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
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.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
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 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
2871 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2872
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2873
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2874
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
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.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
2877
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2878 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2879 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
2880
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2881
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2882
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
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.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
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 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
2888 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
2889 (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
2890
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2891
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2892
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2893
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2894 <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
2895
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2896 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2897 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
2898 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
2899
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2900
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2901
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2902
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2903 <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
2904 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2905 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
2906
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2910 <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
2911
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2912 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2913 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
2914 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
2915
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2919 <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
2920 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2921 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
2922
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2926 <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
2927
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2928 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2929 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
2930
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2931
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2932
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2933
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2934 <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
2935
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2936 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2937 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
2938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2941
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2942 <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
2943
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2944 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2945 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
2946
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2948
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2949
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2950 <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
2951
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2953 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2954 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2955 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
2956 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
2957 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
2958 <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
2959 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
2960 (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
2961 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
2962
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2965 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
2966 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
2967 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
2968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2970
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2971
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2972 <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
2973
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2974 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2975 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
2976
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2977
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2978
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2979
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2980 <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
2981
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2982 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2983 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
2984 (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
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.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
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 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
2993
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2994
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2996
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2997
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2998
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2999
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3000
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3001 <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
3002
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3003 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3004 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
3005 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
3006 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
3007 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3008 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
3009 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3013 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
3014 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
3015 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
3016 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
3017 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
3018
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3019
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3020 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3021 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
3022 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
3023 <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
3024 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
3025
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3026
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3027 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3028 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3029 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
3030 (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
3031 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
3032 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
3033 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3034 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
3035 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3036 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
3037 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
3038
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3039
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3040 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3041 <hr><h3><a name="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
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 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
3046 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
3047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3048
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3049
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3050
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3051 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3052 <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
3053
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3055 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3056 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
3057
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3058
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 <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
3063
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3065 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3066 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
3067 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
3068 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
3069 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
3070 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3071 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
3072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3073
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3074 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3075 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
3076 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
3077
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3078
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3079
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3082 <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
3083
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3084
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3085 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3086 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
3087 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
3088 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
3089 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
3090 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
3091
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3092
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3093 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3094 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
3095 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
3096 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
3097 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
3098
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3099
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3100 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3101 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
3102 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
3103
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3104
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3105
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3106
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3107 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3108 <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
3109
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3110
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3111 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3112 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
3113 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
3114 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
3115 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
3116
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3117
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3118 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3119 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
3120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3121 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3122 <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
3123 <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
3124 <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
3125 <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
3126 <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
3127 <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
3128 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
3129 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3130 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
3131 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
3132
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3133
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3134
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3135
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3136 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3137 <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
3138
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3139
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3140 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3141 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
3142
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3143
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3144
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3145
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3146 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3147 <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
3148
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3149
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3150 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3151 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
3152 on all platforms.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3153
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3154
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3155 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3156 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
3157 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
3158 (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
3159 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
3160 (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
3161
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3162
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3163
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3164
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3165 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3166 <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
3167
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3168
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3169 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3170 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
3171
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3172
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3173
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3174
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3175 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3176 <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
3177
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3178
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3179 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3180 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
3181 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
3182 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
3183
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3184
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3185
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3186
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3187 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3188 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3192 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
3193 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
3194 <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
3195 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
3196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3197
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3198
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3200 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3201 <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
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 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
3206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3207
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3208
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3209
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3210 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3211 <hr><h3><a name="pdf-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
3212
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3213
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3214 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3215 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3216 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
3217 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
3218 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
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 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
3223 <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
3224 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3228
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3229 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3230 <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
3231
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3232
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3233 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3234 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
3235
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3236
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3237
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3238
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3239 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3240 <hr><h3><a name="pdf-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
3241
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3242
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3243 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3244 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
3245 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
3246 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
3247 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
3248 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
3249 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
3250
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3251 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3252 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
3253 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3254 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
3255 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
3256 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
3257 when the loop ends.
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 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
3262 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
3263
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3264
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3265
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3266
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3267 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3268 <hr><h3><a name="pdf-file: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
3269
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3270
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3271 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3272 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
3273 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
3274 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3275 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
3276 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
3277 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3278 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
3279 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3280 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
3281 (see below).
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 The available formats are
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3288
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3289 <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
3290 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
3291 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
3292 (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
3293 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
3294 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
3295 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
3296 (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
3297 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
3298 </li>
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 <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
3301 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
3302 </li>
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 <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
3305 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
3306 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
3307 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3308
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3309 <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
3310 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
3311 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
3312 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
3313 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3314
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3315 <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
3316 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
3317 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
3318 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3319
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3320 <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
3321 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
3322 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
3323 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
3324 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
3325 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
3326 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3327
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3328 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3329 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
3330
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3333
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3334 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3335 <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
3336
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3338 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3339 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
3340 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
3341 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
3342 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
3343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3344 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3345 <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
3346 <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
3347 <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
3348 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3349 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
3350 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
3351 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
3352 plus a string describing the error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3353
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3354
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3355 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3356 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
3357 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
3358 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
3359 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
3360 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
3361 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
3362 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
3363 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
3364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3365
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3366
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3367
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3368 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3369 <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
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 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
3374 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
3375
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3376 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3377
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3378 <li><b>"<code>no</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3379 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
3380 </li>
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 <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
3383 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
3384 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
3385 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
3386 </li>
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 <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
3389 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
3390 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
3391 (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
3392 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3393
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3394 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3395 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
3396 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
3397 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
3398
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3399
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3400
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3401
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3402 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3403 <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
3404
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3405
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3406 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3407 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
3408 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
3409
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3412 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
3413 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
3414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3415
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3417
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3418
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3419
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3420
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3421 <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
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 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
3425
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3426
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3427 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3428 <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
3429
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3430
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3431 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3432 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
3433 used by the program.
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3439 <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
3440
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3441
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3442 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3443 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
3444 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
3445
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3447 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3448 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
3449 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
3450 (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
3451 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3455 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
3456 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
3457 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3458 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
3459 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
3460 <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
3461 <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
3462 <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
3463 <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
3464 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
3465 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
3466 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
3467
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3468
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3469 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3470 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
3471 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
3472 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
3473
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3475 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3476 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3477 <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
3478 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
3479 (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
3480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3482 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3483 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3484 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
3485 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
3486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3487
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3488
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3489
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3490 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3491 <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
3492
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3493
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3494 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3495 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
3496 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
3497 (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
3498 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
3499 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
3500
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3501
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3502
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3504 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3505 <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
3506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3507
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3508 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3509 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
3510 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
3511 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
3512 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
3513 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
3514 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3515 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
3516 as follows:
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 <ul>
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 <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
3521 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3522 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
3523 </li>
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 <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
3526 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
3527 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
3528 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3529
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3530 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3531
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3532 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3533 When called without a <code>command</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3534 <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
3535
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3538
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3539 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3540 <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
3541
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3542
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3543 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3544 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
3545 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
3546 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
3547 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
3548 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
3549 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
3550 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
3551 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3555 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
3556 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
3557
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3558
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3559
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3560
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3561 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3562 <hr><h3><a name="pdf-os.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
3563
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3564
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3565 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3566 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
3567 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
3568
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3569
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3570
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3571
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3572 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3573 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3577 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
3578 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3579 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
3580 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
3581
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3582
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3583
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3584
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3585 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3586 <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
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 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
3591 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
3592 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
3593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3594
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3595
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3596
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3597 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3598 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3602 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
3603 <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
3604 <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
3605 <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
3606 <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
3607 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
3608 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
3609 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3613 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
3614 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
3615 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
3616 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
3617
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3618
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3619 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3620 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
3621 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
3622 for the given category.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3623
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3624
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3625 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3626 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
3627 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
3628
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3629
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3630
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3631
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3632 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3633 <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
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 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
3638 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
3639 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
3640 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3641 <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
3642 <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
3643 <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
3644 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
3645 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3649 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
3650 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
3651 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
3652 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
3653 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
3654 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
3655 <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
3656
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3657
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3658
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3659
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3660 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3661 <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
3662
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3663
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3664 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3665 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
3666 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
3667 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
3668 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
3669
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3670
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3671 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3672 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3673 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
3674 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3675 (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
3676 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
3677 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
3678 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
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 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3683 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
3684 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
3685
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3686
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3688
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3689
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3690
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3691
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3692 <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
3693
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3694 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3695 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3696 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
3697 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
3698 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3699 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
3700 (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
3701 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
3702 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
3703 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
3704 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
3705 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
3706
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3707
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3708 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3709 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
3710 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
3711 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
3712 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
3713 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3714 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
3715
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3716
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3717 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3718 <hr><h3><a name="pdf-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
3719
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3720
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3721 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3722 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
3723 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
3724 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
3725 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
3726 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
3727 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
3728 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
3729
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3730
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3731 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3732 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
3733 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
3734
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3735
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3736
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3737
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 <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
3740
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3741
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3742 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3743 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
3744 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
3745 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
3746 (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
3747
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3748
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3749
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3751 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3752 <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
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 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
3757 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
3758 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
3759 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
3760 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3761 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
3762 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
3763 (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
3764 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3765 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
3766 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
3767
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3768
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3769 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3770 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
3771 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
3772 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
3773 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
3774 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3775 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
3776 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
3777 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3778 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
3779 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
3780 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3781
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3782
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3783 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3784 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
3785 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
3786 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
3787 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
3788 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
3789 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
3790
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3791
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3792
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3793
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3794 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3795 <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
3796
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3797
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3798 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3799 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
3800 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
3801 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
3802 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
3803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3804
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3805 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3806 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
3807 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
3808 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
3809 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
3810 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
3811 -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
3812 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
3813 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
3814 (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
3815
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3816
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3817 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3818 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
3819 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
3820 (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
3821 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
3822
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3823
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3824 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3825 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
3826 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
3827
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3828
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3829
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3830
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3831 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3832 <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
3833
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3834
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3835 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3836 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
3837 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
3838
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3839
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3840
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3841
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3842 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3843 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3847 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
3848
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3849
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3850
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3851
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 <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
3854
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3855
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3856 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3857 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
3858 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
3859 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
3860
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3861
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3862 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3863 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
3864 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
3865 (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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3870 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3871 <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
3872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3873
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3874 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3875 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
3876 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
3877 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3878
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3879
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3880
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3881
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3882 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3883 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3887 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
3888 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
3889 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
3890 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
3891 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3892
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3893 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3894 <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
3895 <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
3896 <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
3897 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3898 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3899 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
3900 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
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 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3905 <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
3906
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3907
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3908 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3909 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
3910 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
3911 <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
3912 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3913 <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
3914 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3915 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
3916 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3917 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
3918 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3919 (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
3920 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
3921
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3922
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3923
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3924
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3925 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3926 <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
3927
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3928
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3929 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3930 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
3931 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
3932 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
3933 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
3934 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
3935 (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
3936 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
3937
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3939 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3940 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
3941 variable indices and names.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3942
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3943
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3944
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3945
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 <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
3948
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3949
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3950 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3951 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
3952 (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
3953 Returns <code>value</code>.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3957
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3958 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3959 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3963 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
3964 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
3965 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
3966 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3967 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
3968
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3970
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3971
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3972 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3973 <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
3974
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3975
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3976 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3977 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
3978 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
3979 <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
3980
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3981
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3982 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3983 Returns <code>udata</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3984
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3985
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3986
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3989 <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
3990
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3993 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
3994 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
3995 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3996 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
3997 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
3998 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
3999 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
4000 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4001 (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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4006 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4007 <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
4008
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4009
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4010 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4011 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
4012 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
4013 from the given function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4014
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4015
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4016 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4017 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
4018 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4019 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
4020 (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
4021 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
4022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4023
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4024
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4025
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4026 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4027 <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
4028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4029
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4030 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4031 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
4032 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
4033
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4034
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4035
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4036
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4037
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4038
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4039
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4040 <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
4041
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4042 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4043 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
4044 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
4045 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
4046 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
4047 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
4048 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
4049 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4050 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
4051 Its usage is:
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4054 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4055 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4056 The options are:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4057
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4058 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4059 <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
4060 <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
4061 <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
4062 <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
4063 <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
4064 <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
4065 <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
4066 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4067 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
4068 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4069 <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
4070 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
4071 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
4072
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4073
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4074 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4075 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
4076 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
4077 (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
4078 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4079 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
4080 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
4081 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
4082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4083
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4084 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4085 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
4086 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
4087 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4088 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
4089 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4090 <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
4091 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
4092
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4093
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4094 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4095 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
4096 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
4097
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4098 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4099 $ 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
4100 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4101 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
4102 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
4103 (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
4104
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4105
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4106 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4107 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4108 <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
4109 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
4110 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
4111 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
4112 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4113 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
4114 (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
4115 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4116 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
4117
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4118 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4119 $ 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
4120 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4121 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
4122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4123 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4124 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
4125 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4126 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4127 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4128 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
4129 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
4130 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
4131 For instance, the call
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4132
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4133 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4134 $ 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
4135 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4136 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
4137 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
4138 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
4139 <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
4140 (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
4141 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
4142
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4143
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4144 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4145 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4146 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
4147 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4148 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
4149 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
4150 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
4151 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
4152 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
4153 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
4154
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4155
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4156 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4157 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
4158 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
4159 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
4160 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
4161 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
4162 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
4163 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
4164
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4165
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4166 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4167 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4168 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
4169 (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
4170 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
4171 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
4172
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4173
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4174 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4175 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
4176 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
4177 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4178 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
4179 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
4180 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
4181 as in
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4184 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4185 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4186 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4187 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
4188 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
4189 then
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4192 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4193 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4194 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
4195
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4196
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4197
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4198 <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
4199
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4200 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4201 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
4202 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
4203 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
4204 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
4205 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4206 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
4207
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4208
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4209 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4210 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
4211 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
4212 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
4213 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
4214 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4215 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
4216 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4217 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
4218 using a new version.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4220
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4221 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4222 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
4223 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4224 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
4225
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4226
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4227 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4228 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
4229 change between versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4230
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4231
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4232
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4233 <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
4234 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4235
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4236 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4237 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
4238 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
4239 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
4240 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4241 (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
4242 can give different results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4243
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4244
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4245 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4246 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
4247 (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
4248 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
4249 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
4250 (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
4251 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4252 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
4253 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4254 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
4255 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
4256 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4257
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4258 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4259 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
4260 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
4261 (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
4262 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
4263 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
4264 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
4265
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4266
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4267 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4268 (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
4269 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
4270 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
4271 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4272
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4273 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4274 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
4275 (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
4276 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4277
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4278 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4279
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4280
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4281
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4283 <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
4284 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4285
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4286 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4287 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
4288 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
4289 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
4290 (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
4291 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
4292 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4293
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4294 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4295 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
4296 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
4297 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4300 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
4301 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
4302 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4303
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4304 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4305 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
4306 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
4307 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4308
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4309 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4310 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
4311 <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
4312 <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
4313 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
4314 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
4315 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
4316 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
4317 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4318 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
4319 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4320 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4321
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4322 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4323 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
4324 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
4325 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
4326 (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
4327 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
4328 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
4329 (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
4330 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
4331 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4332
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4333 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4334
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4335
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4336
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4337
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4338 <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
4339
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4340
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4341 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4342
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4343 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4344 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
4345 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
4346 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
4347 Adapt your code accordingly.
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4351 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
4352 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
4353 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4356 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
4357 (<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
4358 <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
4359 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4360 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
4361 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4362
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4363 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4364 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
4365 (<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
4366 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4367 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
4368 (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
4369 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4370
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4371 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4372
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4373
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4374
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4375
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4376 <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
4377
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4378 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4379 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
4380 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
4381 {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
4382 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
4383 (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
4384 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
4385 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4386 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
4387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4388
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4389
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4393 chunk ::= block
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 block ::= {stat} [retstat]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4396
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4397 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
4398 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
4399 functioncall |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4400 label |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4401 <b>break</b> |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4402 <b>goto</b> Name |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4403 <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
4404 <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
4405 <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
4406 <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
4407 <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
4408 <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
4409 <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
4410 <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
4411 <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
4412
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4413 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
4414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4415 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
4416
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4417 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
4418
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4419 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
4420
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4421 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
4422
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4423 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
4424
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4425 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
4426
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4427 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
4428 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
4429
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4430 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
4431
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4432 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
4433
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4434 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
4435
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4436 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
4437
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4438 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
4439
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4440 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
4441
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4442 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
4443
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4444 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
4445
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4446 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
4447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4448 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
4449
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4450 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
4451 &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
4452 &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
4453 <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
4454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4455 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
4456
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4457 </pre>
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 <p>
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4462
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4463
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4464
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4465
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4468 <HR>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4469 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4470 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4471 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
4472 </SMALL>
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 Last change: minor edit
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
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parents:
diff changeset
4476
391
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
Franklin Schmidt <fschmidt@gmail.com>
parents: 389
diff changeset
4477 </body>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
Franklin Schmidt <fschmidt@gmail.com>
parents: 389
diff changeset
4478 </html>