annotate website/src/manual.html.luan @ 681:f1c935be546d

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1 local Luan = require "luan:Luan"
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2 local Io = require "luan:Io"
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3 local Html = require "luan:Html"
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4 local Http = require "luan:http/Http"
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5 local Shared = require "site:/Shared"
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6
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7
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8 return function()
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9 Io.stdout = Http.response.text_writer()
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10 %>
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11 <html>
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12 <head>
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13 <title>Luan Reference Manual</title>
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14 <style>
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15 @import "/site.css";
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16 </style>
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17 </head>
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18 <body>
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19
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20 <div container>
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21 <% Shared.header() %>
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22
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23 <h1>Luan Reference Manual</h1>
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24
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25 <p small>
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26 Original copyright &copy; 2015 Lua.org, PUC-Rio.
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27 Freely available under the terms of the
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28 <a href="http://www.lua.org/license.html">Lua license</a>.
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29 Modified for Luan.
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30 </p>
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31
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32 <hr/>
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33
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34 <h2>Contents</h2>
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35
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36 <div contents><a href="#intro">Introduction</a></div>
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37
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38 <div contents>
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39 <a href="#basic">Basic Concepts</a>
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40 <ul>
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41 <li><a href="#types">Values and Types</a></li>
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42 <li><a href="#env">Environments</a></li>
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43 <li><a href="#error">Error Handling</a></li>
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44 <li><a href="#meta">Metatables and Metamethods</a></li>
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45 <li><a href="#gc">Garbage Collection</a></li>
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46 </ul>
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47 </div>
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48
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49 <div contents>
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50 <a href="#lang">The Language</a>
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51 <ul>
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52 <li><a href="#lex">Lexical Conventions</a></li>
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53 <li><a href="#vars">Variables</a></li>
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54 <li>
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55 <a href="#stmts">Statements</a>
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56 <ul>
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57 <li><a href="#blocks">Blocks</a></li>
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58 <li><a href="#chunks">Chunks</a></li>
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59 <li><a href="#assignment">Assignment</a></li>
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60 <li><a href="#control">Control Structures</a></li>
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61 <li><a href="#for">For Statement</a></li>
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62 <li><a href="#fn_stmt">Function Calls as Statements</a></li>
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63 <li><a href="#local_stmt">Local Declarations</a></li>
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64 <li><a href="#template_stmt">Template Statements</a></li>
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65 </ul>
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66 </li>
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67 <li>
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68 <a href="#expressions">Expressions</a>
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69 <ul>
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70 <li><a href="#arithmetic">Arithmetic Operators</a></li>
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71 <li><a href="#conversions">Coercions and Conversions</a></li>
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72 <li><a href="#relational">Relational Operators</a></li>
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73 <li><a href="#logical_ops">Logical Operators</a></li>
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74 <li><a href="#concatenation">Concatenation</a></li>
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75 <li><a href="#length">The Length Operator</a></li>
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76 <li><a href="#precedence">Precedence</a></li>
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77 <li><a href="#constructors">Table Constructors</a></li>
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78 <li><a href="#fn_calls">Function Calls</a></li>
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79 <li><a href="#fn_def">Function Definitions</a></li>
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80 <li><a href="#template_expr">Template Expressions</a></li>
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81 </ul>
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82 </li>
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83 <li><a href="#visibility">Visibility Rules</a></li>
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84 </ul>
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85 </div>
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86
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87 <div contents>
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88 <a href="#libs">Standard Libraries</a>
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89 <ul>
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90 <li><a href="#default_lib">Default Environment</a></li>
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91 <li><a href="#luan_lib">Basic Functions</a></li>
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92 <li><a href="#package_lib">Modules</a></li>
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93 <li><a href="#string_lib">String Manipulation</a></li>
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94 <li><a href="#binary_lib">Binary Manipulation</a></li>
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95 <li><a href="#table_lib">Table Manipulation</a></li>
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96 <li><a href="#number_lib">Number Manipulation</a></li>
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97 <li><a href="#math_lib">Mathematical Functions</a></li>
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98 </ul>
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99 </div>
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100
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101 <hr/>
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102
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103
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104 <h2 heading><a name="intro">Introduction</a></h2>
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105
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106 <p>Luan is a high level programming language based on <a href="http://www.lua.org">Lua</a>. A great strength of Lua is its simplicity and Luan takes this even further, being even simpler than Lua. The goal is to provide a simple programming language for the casual programmer with as few concepts as possible so that one can quickly learn the language and then easily understand any code written in Luan.</p>
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107
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108 <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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109
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110 <p>Unlike Lua which is meant to be embedded, Luan is meant to be a full scripting language. This done not by adding feature to Luan, but rather by providing a complete set of libraries.</p>
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112
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113 <h2 heading><a name="basic">Basic Concepts</a></h2>
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114
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115 <p>This section describes the basic concepts of the language.</p>
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116
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117 <h3 heading><a name="types">Values and Types</a></h3>
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118
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119 <p>
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120 Luan is a <em>dynamically typed language</em>.
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121 This means that
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122 variables do not have types; only values do.
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123 There are no type definitions in the language.
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124 All values carry their own type.
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127 <p>
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128 All values in Luan are <em>first-class values</em>.
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129 This means that all values can be stored in variables,
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130 passed as arguments to other functions, and returned as results.
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133 <p>
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134 There are eight basic types in Luan:
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135 <em>nil</em>, <em>boolean</em>, <em>number</em>,
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136 <em>string</em>, <em>binary</em>, <em>function</em>, <em>java</em>,
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137 and <em>table</em>.
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138 <em>Nil</em> is the type of the value <b>nil</b>,
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139 whose main property is to be different from any other value;
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140 it usually represents the absence of a useful value.
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141 <em>Nil</em> is implemented as the Java value <em>null</em>.
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142 <em>Boolean</em> is the type of the values <b>false</b> and <b>true</b>.
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143 <em>Boolean</em> is implemented as the Java class <em>Boolean</em>.
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144 <em>Number</em> represents both
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145 integer numbers and real (floating-point) numbers.
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146 <em>Number</em> is implemented as the Java class <em>Number</em>. Any Java subclass of <em>Number</em> is allowed and this is invisible to the Luan user. Operations on numbers follow the same rules of
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147 the underlying Java implementation.
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148
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149 <em>String</em> is implemented as the Java class <em>String</em>.
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150 <em>Binary</em> is implemented as the Java type <em>byte[]</em>.
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151
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152
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153 <p>
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154 Luan can call (and manipulate) functions written in Luan and
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155 functions written in Java (see <a href="#fn_calls">Function Calls</a>).
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156 Both are represented by the type <em>function</em>.
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157
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158
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159 <p>
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160 The type <em>java</em> is provided to allow arbitrary Java objects to
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161 be stored in Luan variables.
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162 A <em>java</em> value is a Java object that isn't one of the standard Luan types.
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163 Java values have no predefined operations in Luan,
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164 except assignment and identity test.
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165 Java values are useful when Java access is enabled in Luan
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166
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167
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168
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169 <p>
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170 The type <em>table</em> implements associative arrays,
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171 that is, arrays that can be indexed not only with numbers,
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172 but with any Luan value except <b>nil</b>.
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173 Tables can be <em>heterogeneous</em>;
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174 that is, they can contain values of all types (except <b>nil</b>).
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175 Any key with value <b>nil</b> is not considered part of the table.
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176 Conversely, any key that is not part of a table has
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177 an associated value <b>nil</b>.
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178
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179
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180 <p>
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181 Tables are the sole data-structuring mechanism in Luan;
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182 they can be used to represent ordinary arrays, sequences,
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183 symbol tables, sets, records, graphs, trees, etc.
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184 To represent records, Luan uses the field name as an index.
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185 The language supports this representation by
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186 providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
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187 There are several convenient ways to create tables in Luan
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188 (see <a href="#constructors">Table Constructors</a>).
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189
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190
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191 <p>
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192 We use the term <em>sequence</em> to denote a table where
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193 the set of all positive numeric keys is equal to {1..<em>n</em>}
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194 for some non-negative integer <em>n</em>,
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195 which is called the length of the sequence (see <a href="#length">The Length Operator</a>).
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196
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197
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198 <p>
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199 Like indices,
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200 the values of table fields can be of any type.
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201 In particular,
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202 because functions are first-class values,
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203 table fields can contain functions.
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204 Thus tables can also carry <em>methods</em> (see <a href="#fn_def">Function Definitions</a>).
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205
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206
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207 <p>
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208 The indexing of tables follows
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209 the definition of raw equality in the language.
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210 The expressions <code>a[i]</code> and <code>a[j]</code>
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211 denote the same table element
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212 if and only if <code>i</code> and <code>j</code> are raw equal
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213 (that is, equal without metamethods).
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214 In particular, floats with integral values
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215 are equal to their respective integers
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216 (e.g., <code>1.0 == 1</code>).
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217
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218
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219 <p>
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220 Luan values are <em>objects</em>:
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221 variables do not actually <em>contain</em> values,
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222 only <em>references</em> to them.
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223 Assignment, parameter passing, and function returns
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224 always manipulate references to values;
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225 these operations do not imply any kind of copy.
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226
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227
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228 <p>
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229 The library function <a href="#Luan.type"><code>Luan.type</code></a> returns a string describing the type
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230 of a given value.
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231
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232
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233
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234
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235
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236 <h3 heading><a name="env">Environments</a></h3>
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237
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238 <p>
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239 The environment of a chunk starts with only two local variables: <code><a href="#require">require</a></code> and <code><a href="#java">java</a></code>. These are functions are used to load and access libraries and other modules. All other variables must be added to the environment using <a href="http://localhost:8080/manual.html#local_stmt">local declarations</a>.
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240
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241 <p>
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242 As will be discussed in <a href="#vars">Variables</a> and <a href=#assignment">Assignment</a>,
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243 any reference to a free name
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244 (that is, a name not bound to any declaration) <code>var</code>
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245 can be syntactically translated to <code>_ENV.var</code> if <code>_ENV</code> is defined.
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246
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247
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248 <h3 heading><a name="error">Error Handling</a></h3>
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249
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250 <p>
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251 Luan code can explicitly generate an error by calling the
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252 <a href="#Luan.error"><code>error</code></a> function.
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253 If you need to catch errors in Luan,
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254 you can use <a href="#Luan.pcall"><code>pcall</code></a> or <a href="#Luan.try"><code>try</code></a>
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255 to call a given function in <em>protected mode</em>.
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256
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257
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258 <p>
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259 Whenever there is an error,
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260 an <em>error table</em>
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261 is propagated with information about the error.
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262 See <a href="#Luan.new_error"><code>Luan.new_error</code></a>.
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263
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264
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265
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266 <h3 heading><a name="meta">Metatables and Metamethods</a></h3>
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267
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268 <p>
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269 Every table in Luan can have a <em>metatable</em>.
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270 This <em>metatable</em> is an ordinary Luan table
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271 that defines the behavior of the original value
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272 under certain special operations.
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273 You can change several aspects of the behavior
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274 of operations over a value by setting specific fields in its metatable.
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275 For instance, when a table is the operand of an addition,
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276 Luan checks for a function in the field "<code>__add</code>" of the table's metatable.
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277 If it finds one,
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278 Luan calls this function to perform the addition.
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279
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280
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281 <p>
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282 The keys in a metatable are derived from the <em>event</em> names;
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283 the corresponding values are called <ii>metamethods</em>.
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284 In the previous example, the event is <code>"add"</code>
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285 and the metamethod is the function that performs the addition.
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286
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287
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288 <p>
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289 You can query the metatable of any table
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290 using the <a href="#Luan.get_metatable"><code>get_metatable</code></a> function.
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291
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292
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293 <p>
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294 You can replace the metatable of tables
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295 using the <a href="#Luan.set_metatable"><code>set_metatable</code></a> function.
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296
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297
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298 <p>
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299 A metatable controls how a table behaves in
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300 arithmetic operations, bitwise operations,
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301 order comparisons, concatenation, length operation, calls, and indexing.
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302
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303
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304 <p>
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305 A detailed list of events controlled by metatables is given next.
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306 Each operation is identified by its corresponding event name.
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307 The key for each event is a string with its name prefixed by
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308 two underscores, '<code>__</code>';
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309 for instance, the key for operation "add" is the
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310 string "<code>__add</code>".
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311 Note that queries for metamethods are always raw;
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312 the access to a metamethod does not invoke other metamethods.
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313 You can emulate how Luan queries a metamethod for an object <code>obj</code>
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314 with the following code:
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315
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316 <pre>
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317 raw_get(get_metatable(obj) or {}, "__" .. event_name)
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318 </pre>
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319
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320 <p>
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321 Here are the events:
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322
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323 <ul>
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324
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325 <li><p><b>"add": </b>
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326 the <code>+</code> operation.
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327
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328 If any operand for an addition is a table,
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329 Luan will try to call a metamethod.
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330 First, Luan will check the first operand (even if it is valid).
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331 If that operand does not define a metamethod for the "<code>__add</code>" event,
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332 then Luan will check the second operand.
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333 If Luan can find a metamethod,
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334 it calls the metamethod with the two operands as arguments,
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335 and the result of the call
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336 (adjusted to one value)
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337 is the result of the operation.
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338 Otherwise,
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339 it raises an error.
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340 </li>
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341
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342 <li><p><b>"sub": </b>
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343 the <code>-</code> operation.
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344
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345 Behavior similar to the "add" operation.
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346 </li>
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347
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348 <li><p><b>"mul": </b>
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349 the <code>*</code> operation.
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350
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351 Behavior similar to the "add" operation.
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352 </li>
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353
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354 <li><p><b>"div": </b>
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355 the <code>/</code> operation.
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356
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357 Behavior similar to the "add" operation.
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358 </li>
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359
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360 <li><p><b>"mod": </b>
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361 the <code>%</code> operation.
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362
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363 Behavior similar to the "add" operation.
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364 </li>
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365
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366 <li><p><b>"pow": </b>
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367 the <code>^</code> (exponentiation) operation.
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368
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369 Behavior similar to the "add" operation.
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370 </li>
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371
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372 <li><p><b>"unm": </b>
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373 the <code>-</code> (unary minus) operation.
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374
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375 Behavior similar to the "add" operation.
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376 </li>
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377
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378 <li><p><b>"concat": </b>
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379 the <code>..</code> (concatenation) operation.
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380
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381 Behavior similar to the "add" operation.
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382 </li>
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383
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384 <li><p><b>"len": </b>
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385 the <code>#</code> (length) operation.
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386
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387 If there is a metamethod,
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388 Luan calls it with the object as argument,
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389 and the result of the call
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390 (always adjusted to one value)
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391 is the result of the operation.
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392 If there is no metamethod but the object is a table,
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393 then Luan uses the table length operation (see <a href="#length">The Length Operator</a>).
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394 Otherwise, Luan raises an error.
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395 </li>
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396
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397 <li><p><b>"eq": </b>
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398 the <code>==</code> (equal) operation.
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399
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400 Behavior similar to the "add" operation,
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401 except that Luan will try a metamethod only when the values
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402 being compared are both tables
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403 and they are not primitively equal.
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404 The result of the call is always converted to a boolean.
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405 </li>
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406
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407 <li><p><b>"lt": </b>
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408 the <code>&lt;</code> (less than) operation.
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409
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410 Behavior similar to the "add" operation.
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411 The result of the call is always converted to a boolean.
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412 </li>
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413
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414 <li><p><b>"le": </b>
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415 the <code>&lt;=</code> (less equal) operation.
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416
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417 Unlike other operations,
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418 The less-equal operation can use two different events.
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419 First, Luan looks for the "<code>__le</code>" metamethod in both operands,
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420 like in the "lt" operation.
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421 If it cannot find such a metamethod,
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422 then it will try the "<code>__lt</code>" event,
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423 assuming that <code>a &lt;= b</code> is equivalent to <code>not (b &lt; a)</code>.
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424 As with the other comparison operators,
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425 the result is always a boolean.
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426 </li>
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427
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428 <li><p><b>"index": </b>
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429 The indexing access <code>table[key]</code>.
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430
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431 This event happens
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432 when <code>key</code> is not present in <code>table</code>.
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433 The metamethod is looked up in <code>table</code>.
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434
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435
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436 <p>
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437 Despite the name,
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438 the metamethod for this event can be any type.
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439 If it is a function,
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440 it is called with <code>table</code> and <code>key</code> as arguments.
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441 Otherwise
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442 the final result is the result of indexing this metamethod object with <code>key</code>.
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443 (This indexing is regular, not raw,
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444 and therefore can trigger another metamethod if the metamethod object is a table.)
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445 </li>
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446
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447 <li><p><b>"new_index": </b>
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448 The indexing assignment <code>table[key] = value</code>.
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449
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450 Like the index event,
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451 this event happens when
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452 when <code>key</code> is not present in <code>table</code>.
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453 The metamethod is looked up in <code>table</code>.
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454
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455
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456 <p>
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457 Like with indexing,
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458 the metamethod for this event can be either a function or a table.
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459 If it is a function,
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460 it is called with <code>table</code>, <code>key</code>, and <code>value</code> as arguments.
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461 If it is a table,
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462 Luan does an indexing assignment to this table with the same key and value.
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463 (This assignment is regular, not raw,
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464 and therefore can trigger another metamethod.)
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465
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466
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467 <p>
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468 Whenever there is a "new_index" metamethod,
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469 Luan does not perform the primitive assignment.
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470 (If necessary,
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471 the metamethod itself can call <a href="#Luan.raw_set"><code>raw_set</code></a>
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472 to do the assignment.)
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473 </li>
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474
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475 <li><p><b>"call": </b>
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476 The call operation <code>func(args)</code>.
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477
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478 This event happens when Luan tries to call a table.
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479 The metamethod is looked up in <code>func</code>.
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480 If present,
562
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481 the metamethod is called with <code>func</code> as its first argument,
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482 followed by the arguments of the original call (<code>args</code>).
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483 </li>
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484
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485 </ul>
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486
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487
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488
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489
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490 <h3 heading><a name="gc">Garbage Collection</a></h3>
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491
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492 <p>
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493 Luan uses Java's garbage collection.
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494
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diff changeset
495
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496
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497
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498
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499 <h2 heading><a name="lang">The Language</a></h2>
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500
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501 <p>
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502 This section describes the lexis, the syntax, and the semantics of Luan.
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503 In other words,
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504 this section describes
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505 which tokens are valid,
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506 how they can be combined,
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507 and what their combinations mean.
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508
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509
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510 <p>
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511 Language constructs will be explained using the usual extended BNF notation,
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512 in which
562
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513 {<em>a</em>}&nbsp;means&nbsp;0 or more <em>a</em>'s, and
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514 [<em>a</em>]&nbsp;means an optional <em>a</em>.
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515 Non-terminals are shown like non-terminal,
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516 keywords are shown like <b>kword</b>,
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517 and other terminal symbols are shown like &lsquo;<b>=</b>&rsquo;.
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518 The complete syntax of Luan can be found in <a href="#9">&sect;9</a>
371
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519 at the end of this manual.
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520
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521
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522
562
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523 <h3 heading><a name="lex">Lexical Conventions</a></h3>
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524
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525 <p>
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526 Luan ignores spaces and comments
371
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527 between lexical elements (tokens),
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528 except as delimiters between names and keywords.
604
b73f005f3735 table constructor now uses end_of_line as a delimiter
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parents: 589
diff changeset
529 Luan generally considers the end of a line to be the end of a statement. This catches errors and encourages readability. The exception to this is in paranthesis <em>(...)</em> where the end of line is treated as white space.
562
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530
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diff changeset
531 <p>
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532 <em>Names</em>
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533 (also called <em>identifiers</em>)
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534 in Luan can be any string of letters,
371
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535 digits, and underscores,
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536 not beginning with a digit.
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537 Identifiers are used to name variables, table fields, and labels.
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538
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539
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540 <p>
562
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541 The following <em>keywords</em> are reserved
371
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542 and cannot be used as names:
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543
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544
562
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545 <pre>
371
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546 and break do else elseif end
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547 false for function goto if in
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548 local nil not or repeat return
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549 then true until while
562
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550 </pre>
371
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551
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552 <p>
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553 Luan is a case-sensitive language:
562
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554 <code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
371
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555 are two different, valid names.
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556
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557
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558 <p>
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559 The following strings denote other tokens:
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560
562
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diff changeset
561 <pre>
371
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562 + - * / % ^ #
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563 &amp; ~ | &lt;&lt; &gt;&gt; //
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564 == ~= &lt;= &gt;= &lt; &gt; =
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565 ( ) { } [ ] ::
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566 ; : , . .. ...
562
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diff changeset
567 </pre>
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diff changeset
568
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diff changeset
569 <p>
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570 <em>Literal strings</em>
371
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571 can be delimited by matching single or double quotes,
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572 and can contain the following C-like escape sequences:
562
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573 '<code>\a</code>' (bell),
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574 '<code>\b</code>' (backspace),
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575 '<code>\f</code>' (form feed),
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576 '<code>\n</code>' (newline),
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577 '<code>\r</code>' (carriage return),
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578 '<code>\t</code>' (horizontal tab),
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579 '<code>\v</code>' (vertical tab),
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580 '<code>\\</code>' (backslash),
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581 '<code>\"</code>' (quotation mark [double quote]),
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diff changeset
582 and '<code>\'</code>' (apostrophe [single quote]).
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583 A backslash followed by a real newline
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584 results in a newline in the string.
562
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585 The escape sequence '<code>\z</code>' skips the following span
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586 of white-space characters,
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587 including line breaks;
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588 it is particularly useful to break and indent a long literal string
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589 into multiple lines without adding the newlines and spaces
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590 into the string contents.
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591
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
592
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593 <p>
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diff changeset
594 Luan can specify any character in a literal string by its numerical value.
371
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595 This can be done
562
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diff changeset
596 with the escape sequence <code>\x<em>XX</em></code>,
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diff changeset
597 where <em>XX</em> is a sequence of exactly two hexadecimal digits,
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diff changeset
598 or with the escape sequence <code>\<em>ddd</em></code>,
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599 where <em>ddd</em> is a sequence of up to three decimal digits.
371
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600 (Note that if a decimal escape sequence is to be followed by a digit,
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601 it must be expressed using exactly three digits.)
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602
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603
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604 <p>
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605 Literal strings can also be defined using a long format
562
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diff changeset
606 enclosed by <em>long brackets</em>.
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607 We define an <em>opening long bracket of level <em>n</em></em> as an opening
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608 square bracket followed by <em>n</em> equal signs followed by another
371
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609 opening square bracket.
562
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diff changeset
610 So, an opening long bracket of level 0 is written as <code>[[</code>,
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611 an opening long bracket of level 1 is written as <code>[=[</code>,
371
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612 and so on.
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613 A <em>closing long bracket</em> is defined similarly;
371
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614 for instance,
562
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615 a closing long bracket of level 4 is written as <code>]====]</code>.
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616 A <em>long literal</em> starts with an opening long bracket of any level and
371
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617 ends at the first closing long bracket of the same level.
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618 It can contain any text except a closing bracket of the same level.
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619 Literals in this bracketed form can run for several lines,
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620 do not interpret any escape sequences,
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621 and ignore long brackets of any other level.
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622 Any kind of end-of-line sequence
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623 (carriage return, newline, carriage return followed by newline,
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624 or newline followed by carriage return)
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625 is converted to a simple newline.
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626
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627
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628 <p>
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diff changeset
629 Any character in a literal string not
371
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630 explicitly affected by the previous rules represents itself.
380
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631 However, Luan opens files for parsing in text mode,
371
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632 and the system file functions may have problems with
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633 some control characters.
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634 So, it is safer to represent
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635 non-text data as a quoted literal with
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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636 explicit escape sequences for non-text characters.
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637
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parents:
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638
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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639 <p>
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640 For convenience,
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641 when the opening long bracket is immediately followed by a newline,
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642 the newline is not included in the string.
380
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diff changeset
643 As an example
371
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644 the five literal strings below denote the same string:
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645
562
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diff changeset
646 <pre>
371
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647 a = 'alo\n123"'
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648 a = "alo\n123\""
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649 a = '\97lo\10\04923"'
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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650 a = [[alo
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
651 123"]]
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652 a = [==[
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diff changeset
653 alo
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diff changeset
654 123"]==]
562
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diff changeset
655 </pre>
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diff changeset
656
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diff changeset
657 <p>
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diff changeset
658 A <em>numerical constant</em> (or <em>numeral</em>)
371
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659 can be written with an optional fractional part
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660 and an optional decimal exponent,
562
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661 marked by a letter '<code>e</code>' or '<code>E</code>'.
380
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diff changeset
662 Luan also accepts hexadecimal constants,
562
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663 which start with <code>0x</code> or <code>0X</code>.
371
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664 Hexadecimal constants also accept an optional fractional part
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665 plus an optional binary exponent,
562
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666 marked by a letter '<code>p</code>' or '<code>P</code>'.
371
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667 A numeric constant with a fractional dot or an exponent
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parents:
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668 denotes a float;
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669 otherwise it denotes an integer.
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670 Examples of valid integer constants are
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671
562
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diff changeset
672 <pre>
371
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673 3 345 0xff 0xBEBADA
562
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diff changeset
674 </pre>
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diff changeset
675
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diff changeset
676 <p>
371
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677 Examples of valid float constants are
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678
562
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diff changeset
679 <pre>
371
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diff changeset
680 3.0 3.1416 314.16e-2 0.31416E1 34e1
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681 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1
562
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diff changeset
682 </pre>
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parents: 556
diff changeset
683
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diff changeset
684 <p>
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diff changeset
685 A <em>comment</em> starts with a double hyphen (<code>--</code>)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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686 anywhere outside a string.
562
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diff changeset
687 If the text immediately after <code>--</code> is not an opening long bracket,
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diff changeset
688 the comment is a <em>short comment</em>,
371
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689 which runs until the end of the line.
562
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diff changeset
690 Otherwise, it is a <em>long comment</em>,
371
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diff changeset
691 which runs until the corresponding closing long bracket.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
692 Long comments are frequently used to disable code temporarily.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
693
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
694
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
695
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
696
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
697
562
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698 <h3 heading><a name="vars">Variables</a></h3>
371
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699
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parents:
diff changeset
700 <p>
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diff changeset
701 Variables are places that store values.
380
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diff changeset
702 There are three kinds of variables in Luan:
371
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diff changeset
703 global variables, local variables, and table fields.
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parents:
diff changeset
704
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
705 <p>
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parents:
diff changeset
706 A single name can denote a global variable or a local variable
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parents:
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707 (or a function's formal parameter,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
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708 which is a particular kind of local variable):
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parents:
diff changeset
709
562
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diff changeset
710 <pre>
371
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diff changeset
711 var ::= Name
562
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diff changeset
712 </pre>
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diff changeset
713
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diff changeset
714 <p>
464
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diff changeset
715 Name denotes identifiers, as defined in <a href="#lex">Lexical Conventions</a>.
371
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parents:
diff changeset
716
512
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parents: 505
diff changeset
717 <p>
562
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diff changeset
718 Local variables are <em>lexically scoped</em>:
371
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diff changeset
719 local variables can be freely accessed by functions
464
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parents: 429
diff changeset
720 defined inside their scope (see <a href="#visibility">Visibility Rules</a>).
371
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parents:
diff changeset
721
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parents:
diff changeset
722
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
723 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
724 Before the first assignment to a variable, its value is <b>nil</b>.
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parents:
diff changeset
725
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
726 <p>
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parents:
diff changeset
727 Square brackets are used to index a table:
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parents:
diff changeset
728
562
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diff changeset
729 <pre>
371
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parents:
diff changeset
730 var ::= prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo;
562
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diff changeset
731 </pre>
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diff changeset
732
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diff changeset
733 <p>
371
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734 The meaning of accesses to table fields can be changed via metatables.
562
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diff changeset
735 An access to an indexed variable <code>t[i]</code> is equivalent to
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diff changeset
736 a call <code>gettable_event(t,i)</code>.
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737 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
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diff changeset
738 <code>gettable_event</code> function.
380
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739 This function is not defined or callable in Luan.
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740 We use it here only for explanatory purposes.)
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741
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diff changeset
742
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743 <p>
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744 The syntax <code>var.Name</code> is just syntactic sugar for
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diff changeset
745 <code>var["Name"]</code>:
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diff changeset
746
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diff changeset
747 <pre>
371
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748 var ::= prefixexp &lsquo;<b>.</b>&rsquo; Name
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diff changeset
749 </pre>
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diff changeset
750
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751 <p>
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752 Global variables are not available by default. To enable global variable, you must define <code>_ENV</code> as a local variable whose value is a table. If <code>_ENV</code> is not defined, then an unrecognized variable name will produce a compile error. If <code>_ENV</code> is defined then an access to an unrecognized variable name will be consider a global variable. So then an acces to global variable <code>x</code>
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753 is equivalent to <code>_ENV.x</code>.
371
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754 Due to the way that chunks are compiled,
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755 <code>_ENV</code> is never a global name (see <a href="#env">Environments</a>).
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756
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diff changeset
757
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diff changeset
758
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diff changeset
759
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760
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diff changeset
761 <h3 heading><a name="stmts">Statements</a></h3>
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diff changeset
762
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diff changeset
763 <p>
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diff changeset
764 Luan supports an almost conventional set of statements,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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765 similar to those in Pascal or C.
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766 This set includes
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767 assignments, control structures, function calls,
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768 and variable declarations.
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diff changeset
769
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
770
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771
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772 <h4 heading><a name="blocks">Blocks</a></h4>
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773
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774 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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775 A block is a list of statements,
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776 which are executed sequentially:
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777
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diff changeset
778 <pre>
371
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779 block ::= {stat}
562
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diff changeset
780 </pre>
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diff changeset
781
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diff changeset
782 <p>
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diff changeset
783 Luan has <em>empty statements</em>
371
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784 that allow you to separate statements with semicolons,
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785 start a block with a semicolon
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786 or write two semicolons in sequence:
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787
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diff changeset
788 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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789 stat ::= &lsquo;<b>;</b>&rsquo;
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diff changeset
790 </pre>
371
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791
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792 <p>
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793 A block can be explicitly delimited to produce a single statement:
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794
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diff changeset
795 <pre>
371
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796 stat ::= <b>do</b> block <b>end</b>
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797 </pre>
389
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798
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diff changeset
799 <p>
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800 Explicit blocks are useful
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801 to control the scope of variable declarations.
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802 Explicit blocks are also sometimes used to
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803 add a <b>return</b> statement in the middle
464
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804 of another block (see <a href="#control">Control Structures</a>).
371
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parents:
diff changeset
805
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parents:
diff changeset
806
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
807
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
808
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
809
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diff changeset
810 <h4 heading><a name="chunks">Chunks</a></h4>
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diff changeset
811
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diff changeset
812 <p>
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diff changeset
813 The unit of compilation of Luan is called a <em>chunk</em>.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
814 Syntactically,
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diff changeset
815 a chunk is simply a block:
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diff changeset
816
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diff changeset
817 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
818 chunk ::= block
562
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diff changeset
819 </pre>
395
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diff changeset
820
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diff changeset
821 <p>
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diff changeset
822 Luan handles a chunk as the body of an anonymous function
371
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823 with a variable number of arguments
464
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diff changeset
824 (see <a href="#fn_def">Function Definitions</a>).
371
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825 As such, chunks can define local variables,
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826 receive arguments, and return values.
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diff changeset
827
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parents:
diff changeset
828
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parents:
diff changeset
829 <p>
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diff changeset
830 A chunk can be stored in a file or in a string inside the host program.
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831 To execute a chunk,
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diff changeset
832 Luan first <em>loads</em> it,
395
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diff changeset
833 compiling the chunk's code,
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diff changeset
834 and then Luan executes the compiled code.
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diff changeset
835
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diff changeset
836
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diff changeset
837
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diff changeset
838
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diff changeset
839
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diff changeset
840 <h4 heading><a name="assignment">Assignment</a></h4>
395
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diff changeset
841
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diff changeset
842 <p>
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diff changeset
843 Luan allows multiple assignments.
371
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844 Therefore, the syntax for assignment
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845 defines a list of variables on the left side
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diff changeset
846 and a list of expressions on the right side.
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847 The elements in both lists are separated by commas:
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diff changeset
848
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diff changeset
849 <pre>
371
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diff changeset
850 stat ::= varlist &lsquo;<b>=</b>&rsquo; explist
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parents:
diff changeset
851 varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
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parents:
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852 explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
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diff changeset
853 </pre>
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diff changeset
854
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855 <p>
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diff changeset
856 Expressions are discussed in <a href="#expressions">Expressions</a>.
371
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diff changeset
857
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parents:
diff changeset
858
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
859 <p>
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diff changeset
860 Before the assignment,
562
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diff changeset
861 the list of values is <em>adjusted</em> to the length of
371
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diff changeset
862 the list of variables.
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diff changeset
863 If there are more values than needed,
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864 the excess values are thrown away.
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diff changeset
865 If there are fewer values than needed,
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866 the list is extended with as many <b>nil</b>'s as needed.
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867 If the list of expressions ends with a function call,
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diff changeset
868 then all values returned by that call enter the list of values,
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diff changeset
869 before the adjustment
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diff changeset
870 (except when the call is enclosed in parentheses; see <a href="#expressions">Expressions</a>).
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diff changeset
871
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parents:
diff changeset
872
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
873 <p>
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parents:
diff changeset
874 The assignment statement first evaluates all its expressions
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diff changeset
875 and only then the assignments are performed.
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diff changeset
876 Thus the code
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diff changeset
877
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diff changeset
878 <pre>
371
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diff changeset
879 i = 3
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diff changeset
880 i, a[i] = i+1, 20
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diff changeset
881 </pre>
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diff changeset
882
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diff changeset
883 <p>
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diff changeset
884 sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
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885 because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
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886 before it is assigned&nbsp;4.
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parents:
diff changeset
887 Similarly, the line
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888
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diff changeset
889 <pre>
371
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diff changeset
890 x, y = y, x
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diff changeset
891 </pre>
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diff changeset
892
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diff changeset
893 <p>
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diff changeset
894 exchanges the values of <code>x</code> and <code>y</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
895 and
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parents:
diff changeset
896
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diff changeset
897 <pre>
371
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898 x, y, z = y, z, x
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diff changeset
899 </pre>
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diff changeset
900
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diff changeset
901 <p>
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diff changeset
902 cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</code>.
371
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903
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diff changeset
904
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diff changeset
905 <p>
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diff changeset
906 The meaning of assignments to global variables
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907 and table fields can be changed via metatables.
562
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908 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
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diff changeset
909 <code>settable_event(t,i,val)</code>.
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910 (See <a href="#meta">Metatables and Metamethods</a> for a complete description of the
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911 <code>settable_event</code> function.
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912 This function is not defined or callable in Luan.
371
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913 We use it here only for explanatory purposes.)
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914
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915
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916 <p>
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diff changeset
917 An assignment to a global name <code>x = val</code>
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918 is equivalent to the assignment
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diff changeset
919 <code>_ENV.x = val</code> (see <a href="#env">Environments</a>).
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920 Global names are only available when <code>_ENV</code> is defined.
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diff changeset
921
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922
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diff changeset
923
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924 <h4 heading><a name="control">Control Structures</a></h4>
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925
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926 <p>
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927 The control structures
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928 <b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and
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929 familiar syntax:
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930
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diff changeset
931 <pre>
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932 stat ::= <b>while</b> exp <b>do</b> block <b>end</b>
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933 stat ::= <b>repeat</b> block <b>until</b> exp
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934 stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b>
562
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diff changeset
935 </pre>
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diff changeset
936
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937 <p>
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eddf7c73373b fix references in the manual
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diff changeset
938 Luan also has a <b>for</b> statement (see <a href="#for">For Statement</a>).
371
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diff changeset
939
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diff changeset
940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
941 <p>
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diff changeset
942 The condition expression of a
395
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943 control structure must be a boolean.
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944 Any other value type will produce an error.
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945 This helps catch errors and makes code more readable.
371
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946
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diff changeset
947
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diff changeset
948 <p>
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diff changeset
949 In the <b>repeat</b>&ndash;<b>until</b> loop,
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950 the inner block does not end at the <b>until</b> keyword,
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951 but only after the condition.
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diff changeset
952 So, the condition can refer to local variables
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953 declared inside the loop block.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
954
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parents:
diff changeset
955
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
956 <p>
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diff changeset
957 The <b>break</b> statement terminates the execution of a
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diff changeset
958 <b>while</b>, <b>repeat</b>, or <b>for</b> loop,
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959 skipping to the next statement after the loop:
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diff changeset
960
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diff changeset
961
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diff changeset
962 <pre>
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963 stat ::= <b>break</b>
562
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diff changeset
964 </pre>
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diff changeset
965
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diff changeset
966 <p>
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967 A <b>break</b> ends the innermost enclosing loop.
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diff changeset
968
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diff changeset
969
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diff changeset
970 <p>
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diff changeset
971 The <b>return</b> statement is used to return values
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972 from a function or a chunk
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973 (which is an anonymous function).
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diff changeset
974
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diff changeset
975 Functions can return more than one value,
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976 so the syntax for the <b>return</b> statement is
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diff changeset
977
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diff changeset
978 <pre>
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diff changeset
979 stat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
562
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diff changeset
980 </pre>
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diff changeset
981
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diff changeset
982
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diff changeset
983
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diff changeset
984
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diff changeset
985 <h4 heading><a name="for">For Statement</a></h4>
395
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diff changeset
986
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diff changeset
987 <p>
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diff changeset
988 The <b>for</b> statement works over functions,
562
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989 called <em>iterators</em>.
395
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diff changeset
990 On each iteration, the iterator function is called to produce a new value,
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diff changeset
991 stopping when this new value is <b>nil</b>.
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992 The <b>for</b> loop has the following syntax:
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993
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diff changeset
994 <pre>
395
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diff changeset
995 stat ::= <b>for</b> namelist <b>in</b> exp <b>do</b> block <b>end</b>
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diff changeset
996 namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
562
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diff changeset
997 </pre>
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diff changeset
998
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999 <p>
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diff changeset
1000 A <b>for</b> statement like
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diff changeset
1001
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1002 <pre>
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diff changeset
1003 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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1004 </pre>
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diff changeset
1005
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1006 <p>
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1007 is equivalent to the code:
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1008
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1009 <pre>
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diff changeset
1010 do
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diff changeset
1011 local <em>f</em> = <em>exp</em>
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1012 while true do
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diff changeset
1013 local <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> = <em>f</em>()
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1014 if <em>var_1</em> == nil then break end
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1015 <em>block</em>
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1016 end
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1017 end
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diff changeset
1018 </pre>
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diff changeset
1019
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diff changeset
1020 <p>
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diff changeset
1021 Note the following:
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diff changeset
1022
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diff changeset
1023 <ul>
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diff changeset
1024
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diff changeset
1025 <li>
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diff changeset
1026 <code><em>exp</em></code> is evaluated only once.
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diff changeset
1027 Its result is an <em>iterator</em> function.
371
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diff changeset
1028 </li>
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parents:
diff changeset
1029
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diff changeset
1030 <li>
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diff changeset
1031 <code><em>f</em></code> is an invisible variable.
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diff changeset
1032 The name is here for explanatory purposes only.
371
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diff changeset
1033 </li>
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diff changeset
1034
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1035 <li>
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diff changeset
1036 You can use <b>break</b> to exit a <b>for</b> loop.
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1037 </li>
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diff changeset
1038
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diff changeset
1039 <li>
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1040 The loop variables <code><em>var_i</em></code> are local to the loop;
371
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1041 you cannot use their values after the <b>for</b> ends.
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diff changeset
1042 If you need these values,
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diff changeset
1043 then assign them to other variables before breaking or exiting the loop.
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1044 </li>
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1045
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diff changeset
1046 </ul>
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diff changeset
1047
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parents:
diff changeset
1048
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diff changeset
1049
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diff changeset
1050
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1051 <h4 heading><a name="fn_stmt">Function Calls as Statements</a></h4>
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1052
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1053 <p>
371
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1054 To allow possible side-effects,
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1055 function calls can be executed as statements:
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1056
562
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1057 <pre>
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1058 stat ::= functioncall
562
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diff changeset
1059 </pre>
395
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diff changeset
1060
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1061 <p>
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1062 In this case, all returned values are thrown away.
464
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1063 Function calls are explained in <a href="#fn_calls">Function Calls</a>.
371
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1064
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1065
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1066
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diff changeset
1067 <h4 heading><a name="local_stmt">Local Declarations</a></h4>
395
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1068
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1069 <p>
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1070 Local variables can be declared anywhere inside a block.
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1071 The declaration can include an initial assignment:
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1072
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1073 <pre>
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1074 stat ::= <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist]
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1075 </pre>
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diff changeset
1076
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1077 <p>
371
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1078 If present, an initial assignment has the same semantics
464
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1079 of a multiple assignment (see <a href="#assignment">Assignment</a>).
371
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1080 Otherwise, all variables are initialized with <b>nil</b>.
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diff changeset
1081
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1082
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1083 <p>
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1084 A chunk is also a block (see <a href="#chunks">Chunks</a>),
371
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1085 and so local variables can be declared in a chunk outside any explicit block.
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1086
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diff changeset
1087
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1088 <p>
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diff changeset
1089 The visibility rules for local variables are explained in <a href="#visibility">Visibility Rules</a>.
371
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1090
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1091
562
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1092 <h4 heading><a name="template_stmt">Template Statements</a></h4>
465
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diff changeset
1093
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1094 <p>Template statements are based on <a href="#template_expr">template exressions</a> and provide the full equivalent of <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a> but in a general way. Template statements write the equivalent template exression to standard output. For example:</p>
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1095
562
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diff changeset
1096 <pre><%=Html.encode[[
465
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diff changeset
1097 local name = "Bob"
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diff changeset
1098 %>
469
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1099 Hello <%= name %>!
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1100 Bye <%= name %>.
465
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1101 <%
562
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diff changeset
1102 ]]%></pre>
465
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diff changeset
1103
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1104 <p>is equivalent to the code:</p>
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1105
562
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diff changeset
1106 <pre><%=Html.encode[[
465
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diff changeset
1107 local name = "Bob"
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diff changeset
1108 require("luan:Io").stdout.write( %>
469
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diff changeset
1109 Hello <%= name %>!
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1110 Bye <%= name %>.
465
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1111 <% )
562
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diff changeset
1112 ]]%></pre>
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diff changeset
1113
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diff changeset
1114
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diff changeset
1115
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1116 <h3 heading><a name="expressions">Expressions</a></h3>
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1117
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1118 <p>
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1119 The basic expressions in Luan are the following:
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1120
562
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1121 <pre>
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1122 exp ::= prefixexp
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1123 exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
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1124 exp ::= Numeral
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diff changeset
1125 exp ::= LiteralString
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1126 exp ::= functiondef
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1127 exp ::= tableconstructor
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diff changeset
1128 exp ::= &lsquo;<b>...</b>&rsquo;
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1129 exp ::= exp binop exp
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1130 exp ::= unop exp
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diff changeset
1131 prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
562
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1132 </pre>
371
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diff changeset
1133
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diff changeset
1134 <p>
464
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diff changeset
1135 Numerals and literal strings are explained in <a href="#lex">Lexical Conventions</a>;
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1136 variables are explained in <a href="#vars">Variables</a>;
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1137 function definitions are explained in <a href="#fn_def">Function Definitions</a>;
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1138 function calls are explained in <a href="#fn_calls">Function Calls</a>;
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1139 table constructors are explained in <a href="#constructors">Table Constructors</a>.
371
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1140 Vararg expressions,
562
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1141 denoted by three dots ('<code>...</code>'), can only be used when
371
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1142 directly inside a vararg function;
464
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diff changeset
1143 they are explained in <a href="#fn_def">Function Definitions</a>.
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diff changeset
1144
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diff changeset
1145
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diff changeset
1146 <p>
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diff changeset
1147 Binary operators comprise arithmetic operators (see <a href="#arithmetic">Arithmetic Operators</a>),
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diff changeset
1148 relational operators (see <a href="#relational">Relational Operators</a>), logical operators (see <a href="#logical_ops">Logical Operators</a>),
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1149 and the concatenation operator (see <a href="#concatenation">Concatenation</a>).
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diff changeset
1150 Unary operators comprise the unary minus (see <a href="#arithmetic">Arithmetic Operators</a>),
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diff changeset
1151 the unary logical <b>not</b> (see <a href="#logical_ops">Logical Operators</a>),
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diff changeset
1152 and the unary <em>length operator</em> (see <a href="#length">The Length Operator</a>).
371
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1153
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parents:
diff changeset
1154
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diff changeset
1155 <p>
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diff changeset
1156 Both function calls and vararg expressions can result in multiple values.
464
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diff changeset
1157 If a function call is used as a statement (see <a href="#fn_stmt">Function Calls as Statements</a>),
371
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1158 then its return list is adjusted to zero elements,
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diff changeset
1159 thus discarding all returned values.
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1160 If an expression is used as the last (or the only) element
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1161 of a list of expressions,
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1162 then no adjustment is made
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1163 (unless the expression is enclosed in parentheses).
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1164 In all other contexts,
395
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1165 Luan adjusts the result list to one element,
371
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diff changeset
1166 either discarding all values except the first one
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parents:
diff changeset
1167 or adding a single <b>nil</b> if there are no values.
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parents:
diff changeset
1168
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parents:
diff changeset
1169
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diff changeset
1170 <p>
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diff changeset
1171 Here are some examples:
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1172
562
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1173 <pre>
371
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1174 f() -- adjusted to 0 results
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1175 g(f(), x) -- f() is adjusted to 1 result
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diff changeset
1176 g(x, f()) -- g gets x plus all results from f()
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1177 a,b,c = f(), x -- f() is adjusted to 1 result (c gets nil)
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parents:
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1178 a,b = ... -- a gets the first vararg parameter, b gets
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diff changeset
1179 -- the second (both a and b can get nil if there
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diff changeset
1180 -- is no corresponding vararg parameter)
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diff changeset
1181
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diff changeset
1182 a,b,c = x, f() -- f() is adjusted to 2 results
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1183 a,b,c = f() -- f() is adjusted to 3 results
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1184 return f() -- returns all results from f()
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1185 return ... -- returns all received vararg parameters
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1186 return x,y,f() -- returns x, y, and all results from f()
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1187 {f()} -- creates a list with all results from f()
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1188 {...} -- creates a list with all vararg parameters
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1189 {f(), nil} -- f() is adjusted to 1 result
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1190 </pre>
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1191
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1192 <p>
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1193 Any expression enclosed in parentheses always results in only one value.
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1194 Thus,
562
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1195 <code>(f(x,y,z))</code> is always a single value,
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1196 even if <code>f</code> returns several values.
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1197 (The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
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1198 or <b>nil</b> if <code>f</code> does not return any values.)
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1199
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1200
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diff changeset
1201
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1202 <h4 heading><a name="arithmetic">Arithmetic Operators</a></h4>
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1203
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1204 <p>
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1205 Luan supports the following arithmetic operators:
371
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1206
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1207 <ul>
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1208 <li><b><code>+</code>: </b>addition</li>
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1209 <li><b><code>-</code>: </b>subtraction</li>
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1210 <li><b><code>*</code>: </b>multiplication</li>
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1211 <li><b><code>/</code>: </b>division</li>
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1212 <li><b><code>%</code>: </b>modulo</li>
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1213 <li><b><code>^</code>: </b>exponentiation</li>
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1214 <li><b><code>-</code>: </b>unary minus</li>
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1215 </ul>
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1216
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1217 <p>
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1218 Addition, subtraction, multiplication, division, and unary minus are the same as these operators in Java. Exponentiation uses Java's <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Math.html#pow(double,%20double)">Math.pow</a> function.
371
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1219
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diff changeset
1220 <p>
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1221 Modulo is defined as the remainder of a division
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1222 that rounds the quotient towards minus infinite (floor division).
395
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1223 (The Java modulo operator is not used.)
371
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1224
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diff changeset
1225
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1226
562
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1227 <h4 heading><a name="conversions">Coercions and Conversions</a></h4>
396
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1228
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1229 <p>
465
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1230 Luan generally avoids automatic conversions.
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1231 String concatenation automatically converts all of its arguments to strings.
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diff changeset
1232
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1233 <p>
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1234 Luan provides library functions for explicit type conversions.
371
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1235
396
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diff changeset
1236
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diff changeset
1237
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1238
562
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1239 <h4 heading><a name="relational">Relational Operators</a></h4>
396
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1240
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1241 <p>
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1242 Luan supports the following relational operators:
371
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1243
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1244 <ul>
562
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1245 <li><b><code>==</code>: </b>equality</li>
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1246 <li><b><code>~=</code>: </b>inequality</li>
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1247 <li><b><code>&lt;</code>: </b>less than</li>
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1248 <li><b><code>&gt;</code>: </b>greater than</li>
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1249 <li><b><code>&lt;=</code>: </b>less or equal</li>
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1250 <li><b><code>&gt;=</code>: </b>greater or equal</li>
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diff changeset
1251 </ul><p>
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parents:
diff changeset
1252 These operators always result in <b>false</b> or <b>true</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1253
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1254
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1255 <p>
562
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diff changeset
1256 Equality (<code>==</code>) first compares the type of its operands.
371
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diff changeset
1257 If the types are different, then the result is <b>false</b>.
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1258 Otherwise, the values of the operands are compared.
396
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diff changeset
1259 Strings, numbers, and binary values are compared in the obvious way (by value).
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diff changeset
1260
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diff changeset
1261 <p>
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diff changeset
1262 Tables
371
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diff changeset
1263 are compared by reference:
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diff changeset
1264 two objects are considered equal only if they are the same object.
396
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diff changeset
1265 Every time you create a new table,
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1266 it is different from any previously existing table.
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1267 Closures are also compared by reference.
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diff changeset
1268
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diff changeset
1269 <p>
417
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diff changeset
1270 You can change the way that Luan compares tables
464
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diff changeset
1271 by using the "eq" metamethod (see <a href="#meta">Metatables and Metamethods</a>).
371
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1272
396
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diff changeset
1273 <p>
562
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diff changeset
1274 Java values are compared for equality with the Java <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#equals(java.lang.Object)"><code>equals</code></a> method.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1275
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parents:
diff changeset
1276 <p>
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parents:
diff changeset
1277 Equality comparisons do not convert strings to numbers
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diff changeset
1278 or vice versa.
562
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diff changeset
1279 Thus, <code>"0"==0</code> evaluates to <b>false</b>,
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1280 and <code>t[0]</code> and <code>t["0"]</code> denote different
371
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1281 entries in a table.
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diff changeset
1282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1283
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diff changeset
1284 <p>
562
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diff changeset
1285 The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
371
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diff changeset
1286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1288 <p>
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diff changeset
1289 The order operators work as follows.
396
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diff changeset
1290
371
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1291 If both arguments are numbers,
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diff changeset
1292 then they are compared following
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diff changeset
1293 the usual rule for binary operations.
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diff changeset
1294 Otherwise, if both arguments are strings,
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diff changeset
1295 then their values are compared according to the current locale.
396
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diff changeset
1296 Otherwise, Luan tries to call the "lt" or the "le"
464
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diff changeset
1297 metamethod (see <a href="#meta">Metatables and Metamethods</a>).
562
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diff changeset
1298 A comparison <code>a &gt; b</code> is translated to <code>b &lt; a</code>
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diff changeset
1299 and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
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diff changeset
1300
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diff changeset
1301
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diff changeset
1302
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diff changeset
1303
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diff changeset
1304
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diff changeset
1305 <h4 heading><a name="logical_ops">Logical Operators</a></h4>
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1306
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1307 <p>
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1308 The logical operators in Luan are
371
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1309 <b>and</b>, <b>or</b>, and <b>not</b>.
396
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diff changeset
1310 The <b>and</b> and <b>or</b> operators consider both <b>false</b> and <b>nil</b> as false
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diff changeset
1311 and anything else as true.
464
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diff changeset
1312 Like the control structures (see <a href="#control">Control Structures</a>),
396
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1313 the <b>not</b> operator requires a boolean value.
371
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diff changeset
1314
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diff changeset
1315 <p>
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diff changeset
1316 The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>.
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1317 The conjunction operator <b>and</b> returns its first argument
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diff changeset
1318 if this value is <b>false</b> or <b>nil</b>;
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1319 otherwise, <b>and</b> returns its second argument.
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diff changeset
1320 The disjunction operator <b>or</b> returns its first argument
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diff changeset
1321 if this value is different from <b>nil</b> and <b>false</b>;
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1322 otherwise, <b>or</b> returns its second argument.
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diff changeset
1323 Both <b>and</b> and <b>or</b> use short-circuit evaluation;
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1324 that is,
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diff changeset
1325 the second operand is evaluated only if necessary.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1326 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1327
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diff changeset
1328 <pre>
371
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diff changeset
1329 10 or 20 --&gt; 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1330 10 or error() --&gt; 10
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diff changeset
1331 nil or "a" --&gt; "a"
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diff changeset
1332 nil and 10 --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1333 false and error() --&gt; false
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diff changeset
1334 false and nil --&gt; false
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1335 false or nil --&gt; nil
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1336 10 and 20 --&gt; 20
562
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diff changeset
1337 </pre>
396
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diff changeset
1338
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diff changeset
1339 <p>
371
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1340 (In this manual,
562
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diff changeset
1341 <code>--&gt;</code> indicates the result of the preceding expression.)
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diff changeset
1342
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diff changeset
1343
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diff changeset
1344
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diff changeset
1345 <h4 heading><a name="concatenation">Concatenation</a></h4>
396
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1346
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diff changeset
1347 <p>
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diff changeset
1348 The string concatenation operator in Luan is
562
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diff changeset
1349 denoted by two dots ('<code>..</code>').
396
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1350 All operands are converted to strings.
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diff changeset
1351
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diff changeset
1352
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diff changeset
1353
562
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diff changeset
1354 <h4 heading><a name="length">The Length Operator</a></h4>
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diff changeset
1355
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1356 <p>
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diff changeset
1357 The length operator is denoted by the unary prefix operator <code>#</code>.
396
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1358 The length of a string is its number of characters.
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1359 The length of a binary is its number of bytes.
371
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1360
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diff changeset
1361
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diff changeset
1362 <p>
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1363 A program can modify the behavior of the length operator for
562
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diff changeset
1364 any table through the <code>__len</code> metamethod (see <a href="#meta">Metatables and Metamethods</a>).
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diff changeset
1365
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diff changeset
1366
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diff changeset
1367 <p>
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diff changeset
1368 Unless a <code>__len</code> metamethod is given,
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diff changeset
1369 the length of a table <code>t</code> is defined
396
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1370 as the number of elements in <em>sequence</em>,
371
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1371 that is,
396
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diff changeset
1372 the size of the set of its positive numeric keys is equal to <em>{1..n}</em>
371
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1373 for some non-negative integer <em>n</em>.
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1374 In that case, <em>n</em> is its length.
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diff changeset
1375 Note that a table like
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1376
562
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1377 <pre>
371
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1378 {10, 20, nil, 40}
562
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diff changeset
1379 </pre>
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diff changeset
1380
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diff changeset
1381 <p>
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diff changeset
1382 has a length of <code>2</code>, because that is the last key in sequence.
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diff changeset
1383
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diff changeset
1384
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parents: 556
diff changeset
1385
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diff changeset
1386
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diff changeset
1387
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diff changeset
1388 <h4 heading><a name="precedence">Precedence</a></h4>
396
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diff changeset
1389
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diff changeset
1390 <p>
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diff changeset
1391 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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diff changeset
1392 from lower to higher priority:
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>
371
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diff changeset
1395 or
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diff changeset
1396 and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1397 &lt; &gt; &lt;= &gt;= ~= ==
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parents:
diff changeset
1398 ..
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diff changeset
1399 + -
396
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diff changeset
1400 * / %
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diff changeset
1401 unary operators (not # -)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1402 ^
562
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diff changeset
1403 </pre>
396
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diff changeset
1404
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diff changeset
1405 <p>
371
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diff changeset
1406 As usual,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1407 you can use parentheses to change the precedences of an expression.
562
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diff changeset
1408 The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
371
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diff changeset
1409 operators are right associative.
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diff changeset
1410 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
1411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1412
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1413
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1414
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1415
562
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diff changeset
1416 <h4 heading><a name="constructors">Table Constructors</a></h4>
396
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diff changeset
1417
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diff changeset
1418 <p>
371
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diff changeset
1419 Table constructors are expressions that create tables.
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parents:
diff changeset
1420 Every time a constructor is evaluated, a new table is created.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1421 A constructor can be used to create an empty table
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1422 or to create a table and initialize some of its fields.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1423 The general syntax for constructors is
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diff changeset
1424
562
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diff changeset
1425 <pre>
604
b73f005f3735 table constructor now uses end_of_line as a delimiter
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parents: 589
diff changeset
1426 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
1427 fieldlist ::= [field] {fieldsep [field]}
371
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parents:
diff changeset
1428 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
1429 fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo; | <b>end_of_line</b>
562
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diff changeset
1430 </pre>
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parents: 556
diff changeset
1431
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diff changeset
1432 <p>
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diff changeset
1433 Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry
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parents: 556
diff changeset
1434 with key <code>exp1</code> and value <code>exp2</code>.
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diff changeset
1435 A field of the form <code>name = exp</code> is equivalent to
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diff changeset
1436 <code>["name"] = exp</code>.
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diff changeset
1437 Finally, fields of the form <code>exp</code> are equivalent to
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diff changeset
1438 <code>[i] = exp</code>, where <code>i</code> are consecutive integers
371
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diff changeset
1439 starting with 1.
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parents:
diff changeset
1440 Fields in the other formats do not affect this counting.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1441 For example,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1442
562
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diff changeset
1443 <pre>
371
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parents:
diff changeset
1444 a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
562
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diff changeset
1445 </pre>
396
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diff changeset
1446
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diff changeset
1447 <p>
371
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parents:
diff changeset
1448 is equivalent to
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parents:
diff changeset
1449
562
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diff changeset
1450 <pre>
371
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parents:
diff changeset
1451 do
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parents:
diff changeset
1452 local t = {}
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1453 t[f(1)] = g
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1454 t[1] = "x" -- 1st exp
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parents:
diff changeset
1455 t[2] = "y" -- 2nd exp
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parents:
diff changeset
1456 t.x = 1 -- t["x"] = 1
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parents:
diff changeset
1457 t[3] = f(x) -- 3rd exp
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parents:
diff changeset
1458 t[30] = 23
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parents:
diff changeset
1459 t[4] = 45 -- 4th exp
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parents:
diff changeset
1460 a = t
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parents:
diff changeset
1461 end
562
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diff changeset
1462 </pre>
371
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parents:
diff changeset
1463
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parents:
diff changeset
1464 <p>
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parents:
diff changeset
1465 The order of the assignments in a constructor is undefined.
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parents:
diff changeset
1466 (This order would be relevant only when there are repeated keys.)
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parents:
diff changeset
1467
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parents:
diff changeset
1468
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parents:
diff changeset
1469 <p>
562
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diff changeset
1470 If the last field in the list has the form <code>exp</code>
371
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parents:
diff changeset
1471 and the expression is a function call or a vararg expression,
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diff changeset
1472 then all values returned by this expression enter the list consecutively
464
eddf7c73373b fix references in the manual
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diff changeset
1473 (see <a href="#fn_calls">Function Calls</a>).
371
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parents:
diff changeset
1474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1476 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1477 The field list can have an optional trailing separator,
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diff changeset
1478 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
1479
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parents:
diff changeset
1480
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diff changeset
1481
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diff changeset
1482
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1483
562
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diff changeset
1484 <h4 heading><a name="fn_calls">Function Calls</a></h4>
417
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diff changeset
1485
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diff changeset
1486 <p>
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diff changeset
1487 A function call in Luan has the following syntax:
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1488
562
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1489 <pre>
371
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diff changeset
1490 functioncall ::= prefixexp args
562
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diff changeset
1491 </pre>
417
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diff changeset
1492
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diff changeset
1493 <p>
371
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diff changeset
1494 In a function call,
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1495 first prefixexp and args are evaluated.
562
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diff changeset
1496 If the value of prefixexp has type <em>function</em>,
371
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diff changeset
1497 then this function is called
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1498 with the given arguments.
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diff changeset
1499 Otherwise, the prefixexp "call" metamethod is called,
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1500 having as first parameter the value of prefixexp,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1501 followed by the original call arguments
464
eddf7c73373b fix references in the manual
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diff changeset
1502 (see <a href="#meta">Metatables and Metamethods</a>).
371
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parents:
diff changeset
1503
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1504
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diff changeset
1505 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1506 Arguments have the following syntax:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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1507
562
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diff changeset
1508 <pre>
371
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diff changeset
1509 args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo;
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1510 args ::= tableconstructor
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1511 args ::= LiteralString
562
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diff changeset
1512 </pre>
417
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diff changeset
1513
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diff changeset
1514 <p>
371
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diff changeset
1515 All argument expressions are evaluated before the call.
562
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diff changeset
1516 A call of the form <code>f{<em>fields</em>}</code> is
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parents: 556
diff changeset
1517 syntactic sugar for <code>f({<em>fields</em>})</code>;
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1518 that is, the argument list is a single new table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1519 A call of the form <code>f'<em>string</em>'</code>
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diff changeset
1520 (or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>)
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1521 is syntactic sugar for <code>f('<em>string</em>')</code>;
371
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parents:
diff changeset
1522 that is, the argument list is a single literal string.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1523
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
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parents:
diff changeset
1525 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1526 A call of the form <code>return <em>functioncall</em></code> is called
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diff changeset
1527 a <em>tail call</em>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1528 Luan implements <em>proper tail calls</em>
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diff changeset
1529 (or <em>proper tail recursion</em>):
371
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parents:
diff changeset
1530 in a tail call,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1531 the called function reuses the stack entry of the calling function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1532 Therefore, there is no limit on the number of nested tail calls that
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parents:
diff changeset
1533 a program can execute.
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parents:
diff changeset
1534 However, a tail call erases any debug information about the
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1535 calling function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1536 Note that a tail call only happens with a particular syntax,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1537 where the <b>return</b> has one single function call as argument;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1538 this syntax makes the calling function return exactly
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1539 the returns of the called function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1540 So, none of the following examples are tail calls:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1541
562
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parents: 556
diff changeset
1542 <pre>
371
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diff changeset
1543 return (f(x)) -- results adjusted to 1
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parents:
diff changeset
1544 return 2 * f(x)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1545 return x, f(x) -- additional results
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1546 f(x); return -- results discarded
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1547 return x or f(x) -- results adjusted to 1
562
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diff changeset
1548 </pre>
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parents: 556
diff changeset
1549
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1550
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1551
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1552
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1553 <h4 heading><a name="fn_def">Function Definitions</a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1554
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1555 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1556 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
1557
562
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parents: 556
diff changeset
1558 <pre>
371
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parents:
diff changeset
1559 functiondef ::= <b>function</b> funcbody
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1560 funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1561 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1562
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1563 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1564 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
1565
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1566 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1567 stat ::= <b>function</b> funcname funcbody
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1568 stat ::= <b>local</b> <b>function</b> Name funcbody
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1569 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
1570 </pre>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1571
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1572 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1573 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1574
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1575 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1576 function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1577 </pre>
417
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parents: 396
diff changeset
1578
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1579 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1580 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1581
562
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parents: 556
diff changeset
1582 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1583 f = function () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1584 </pre>
417
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parents: 396
diff changeset
1585
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1586 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1587 The statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1588
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1589 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1590 function t.a.b.c.f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1591 </pre>
417
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parents: 396
diff changeset
1592
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1593 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1594 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1595
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1596 <pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1597 t.a.b.c.f = function () <em>body</em> end
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diff changeset
1598 </pre>
417
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parents: 396
diff changeset
1599
a40e99cf0b0b work on manual
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diff changeset
1600 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1601 The statement
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>
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1604 local function f () <em>body</em> end
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
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 translates to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1609
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1610 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1611 local f; f = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1612 </pre>
417
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parents: 396
diff changeset
1613
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1614 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1615 not to
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1616
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1617 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1618 local f = function () <em>body</em> end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1619 </pre>
417
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parents: 396
diff changeset
1620
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diff changeset
1621 <p>
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1622 (This only makes a difference when the body of the function
562
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diff changeset
1623 contains references to <code>f</code>.)
371
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1624
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diff changeset
1625
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diff changeset
1626 <p>
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diff changeset
1627 A function definition is an executable expression,
562
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diff changeset
1628 whose value has type <em>function</em>.
417
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diff changeset
1629 When Luan precompiles a chunk,
371
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1630 all its function bodies are precompiled too.
417
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diff changeset
1631 Then, whenever Luan executes the function definition,
562
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1632 the function is <em>instantiated</em> (or <em>closed</em>).
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1633 This function instance (or <em>closure</em>)
371
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1634 is the final value of the expression.
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diff changeset
1635
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diff changeset
1636
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diff changeset
1637 <p>
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1638 Parameters act as local variables that are
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1639 initialized with the argument values:
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1640
562
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diff changeset
1641 <pre>
371
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diff changeset
1642 parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
562
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diff changeset
1643 </pre>
417
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1644
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diff changeset
1645 <p>
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1646 When a function is called,
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1647 the list of arguments is adjusted to
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1648 the length of the list of parameters,
562
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diff changeset
1649 unless the function is a <em>vararg function</em>,
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diff changeset
1650 which is indicated by three dots ('<code>...</code>')
371
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1651 at the end of its parameter list.
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1652 A vararg function does not adjust its argument list;
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1653 instead, it collects all extra arguments and supplies them
562
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1654 to the function through a <em>vararg expression</em>,
371
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1655 which is also written as three dots.
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1656 The value of this expression is a list of all actual extra arguments,
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1657 similar to a function with multiple results.
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1658 If a vararg expression is used inside another expression
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1659 or in the middle of a list of expressions,
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1660 then its return list is adjusted to one element.
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1661 If the expression is used as the last element of a list of expressions,
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1662 then no adjustment is made
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diff changeset
1663 (unless that last expression is enclosed in parentheses).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1664
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1665
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1666 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1667 As an example, consider the following definitions:
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1668
562
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diff changeset
1669 <pre>
371
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diff changeset
1670 function f(a, b) end
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diff changeset
1671 function g(a, b, ...) end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1672 function r() return 1,2,3 end
562
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diff changeset
1673 </pre>
417
a40e99cf0b0b work on manual
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diff changeset
1674
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diff changeset
1675 <p>
371
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diff changeset
1676 Then, we have the following mapping from arguments to parameters and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1677 to the vararg expression:
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diff changeset
1678
562
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diff changeset
1679 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1680 CALL PARAMETERS
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parents:
diff changeset
1681
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1682 f(3) a=3, b=nil
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parents:
diff changeset
1683 f(3, 4) a=3, b=4
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1684 f(3, 4, 5) a=3, b=4
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parents:
diff changeset
1685 f(r(), 10) a=1, b=10
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parents:
diff changeset
1686 f(r()) a=1, b=2
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parents:
diff changeset
1687
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1688 g(3) a=3, b=nil, ... --&gt; (nothing)
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parents:
diff changeset
1689 g(3, 4) a=3, b=4, ... --&gt; (nothing)
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parents:
diff changeset
1690 g(3, 4, 5, 8) a=3, b=4, ... --&gt; 5 8
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diff changeset
1691 g(5, r()) a=5, b=1, ... --&gt; 2 3
562
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diff changeset
1692 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1693
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1694 <p>
464
eddf7c73373b fix references in the manual
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parents: 429
diff changeset
1695 Results are returned using the <b>return</b> statement (see <a href="#control">Control Structures</a>).
371
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diff changeset
1696 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
1697 without encountering a <b>return</b> statement,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1698 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
1699
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1700
562
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diff changeset
1701 <h4 heading><a name="template_expr">Template Expressions</a></h4>
465
47c7de1f2322 documentation work
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parents: 464
diff changeset
1702
47c7de1f2322 documentation work
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parents: 464
diff changeset
1703 <p>Luan template expression are based on <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a>. Template expressions return multiple values. Here is an example:</p>
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parents: 464
diff changeset
1704
562
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diff changeset
1705 <pre><%=Html.encode[[
465
47c7de1f2322 documentation work
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parents: 464
diff changeset
1706 local name = "Bob"
469
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parents: 468
diff changeset
1707 write( %>Hello <%= name %>!<% )
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1708 ]]%></pre>
465
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parents: 464
diff changeset
1709
47c7de1f2322 documentation work
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diff changeset
1710 <p>This is equivalent to the code:</p>
47c7de1f2322 documentation work
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parents: 464
diff changeset
1711
562
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diff changeset
1712 <pre>
465
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parents: 464
diff changeset
1713 local name = "Bob"
47c7de1f2322 documentation work
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parents: 464
diff changeset
1714 write( "Hello ", name, "!" )
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1715 </pre>
465
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parents: 464
diff changeset
1716
47c7de1f2322 documentation work
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parents: 464
diff changeset
1717 <p>The strings in template expressions may be multiple lines.</p>
47c7de1f2322 documentation work
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parents: 464
diff changeset
1718
417
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diff changeset
1719
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diff changeset
1720
562
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diff changeset
1721 <h3 heading><a name="visibility">Visibility Rules</a></h3>
417
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1722
a40e99cf0b0b work on manual
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diff changeset
1723 <p>
a40e99cf0b0b work on manual
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parents: 396
diff changeset
1724 Luan is a lexically scoped language.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1725 The scope of a local variable begins at the first statement after
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1726 its declaration and lasts until the last non-void statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1727 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
1728 Consider the following example:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1729
562
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diff changeset
1730 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1731 x = 10 -- global variable
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1732 do -- new block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1733 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
1734 print(x) --&gt; 10
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1735 x = x+1
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1736 do -- another block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1737 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
1738 print(x) --&gt; 12
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1739 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1740 print(x) --&gt; 11
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1741 end
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1742 print(x) --&gt; 10 (the global one)
562
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diff changeset
1743 </pre>
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parents: 556
diff changeset
1744
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1745 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1746 Notice that, in a declaration like <code>local x = x</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
1747 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
1748 and so the second <code>x</code> refers to the outside variable.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1749
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1751 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1752 Because of the lexical scoping rules,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1753 local variables can be freely accessed by functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1754 defined inside their scope.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1755 A local variable used by an inner function is called
562
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parents: 556
diff changeset
1756 an <em>upvalue</em>, or <em>external local variable</em>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1757 inside the inner function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1758
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
1760 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1761 Notice that each execution of a <b>local</b> statement
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1762 defines new local variables.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1763 Consider the following example:
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parents:
diff changeset
1764
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
1765 <pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
1766 a = {}
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diff changeset
1767 local x = 20
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diff changeset
1768 for i=1,10 do
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
1769 local y = 0
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diff changeset
1770 a[i] = function () y=y+1; return x+y end
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1771 end
562
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diff changeset
1772 </pre>
417
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diff changeset
1773
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diff changeset
1774 <p>
371
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diff changeset
1775 The loop creates ten closures
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1776 (that is, ten instances of the anonymous function).
562
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diff changeset
1777 Each of these closures uses a different <code>y</code> variable,
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diff changeset
1778 while all of them share the same <code>x</code>.
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diff changeset
1779
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diff changeset
1780
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diff changeset
1781
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diff changeset
1782
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diff changeset
1783
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diff changeset
1784 <h2 heading><a name="libs">Standard Libraries</a></h2>
468
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diff changeset
1785
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diff changeset
1786 <p>
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diff changeset
1787 The standard Luan libraries provide useful functions
9b51e2413cab documentation
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diff changeset
1788 that are implemented both in Java and in Luan itself.
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diff changeset
1789 How each function is implemented shouldn't matter to the user.
371
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1790 Some of these functions provide essential services to the language
562
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diff changeset
1791 (e.g., <a href="#Luan.type"><code>type</code></a> and <a href="#Luan.get_metatable"><code>get_metatable</code></a>);
468
9b51e2413cab documentation
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diff changeset
1792 others provide access to "outside" services (e.g., I/O).
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diff changeset
1793
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diff changeset
1794
562
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diff changeset
1795 <h3 heading><a name="default_lib">Default Environment</a></h3>
468
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diff changeset
1796
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diff changeset
1797 <p>
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diff changeset
1798 These are provided by default as local variables for any Luan code as described in <a href="#env">Environments</a>.
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diff changeset
1799
470
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diff changeset
1800
562
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diff changeset
1801 <h4 heading><a name="require"><code>java ()</code></a></h4>
470
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diff changeset
1802
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diff changeset
1803 <p>
5627eb637eb4 documentation
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diff changeset
1804 This function enables Java in the current chunk if that chunk has permission to use Java. If the chunk doesn't have permission to use Java, then an error is thrown.
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diff changeset
1805
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diff changeset
1806
562
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diff changeset
1807 <h4 heading><a name="require"><code>require (mod_uri)</code></a></h4>
470
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diff changeset
1808
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diff changeset
1809 <p>
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diff changeset
1810 Example use:
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diff changeset
1811
562
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diff changeset
1812 <pre>
470
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diff changeset
1813 local Table = require "luan:Table"
562
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diff changeset
1814 </pre>
470
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diff changeset
1815
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diff changeset
1816 <p>
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diff changeset
1817 Could be defined as:
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diff changeset
1818
562
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1819 <pre>
470
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diff changeset
1820 local function require(mod_name)
476
cd22e4694ea3 documentation
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parents: 475
diff changeset
1821 return <a href="#Package.load">Package.load</a>(mod_name) or <a href="#Luan.error">Luan.error</a>("module '"..mod_name.."' not found")
470
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1822 end
562
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diff changeset
1823 </pre>
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diff changeset
1824
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diff changeset
1825
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diff changeset
1826 <h3 heading><a name="luan_lib">Basic Functions</a></h3>
470
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diff changeset
1827
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diff changeset
1828 <p>
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diff changeset
1829 Include this library by:
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diff changeset
1830
562
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diff changeset
1831 <pre>
470
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diff changeset
1832 local Luan = require "luan:Luan"
562
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diff changeset
1833 </pre>
470
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diff changeset
1834
476
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parents: 475
diff changeset
1835 <p>
470
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diff changeset
1836 The basic library provides basic functions to Luan that don't depend on other libaries.
5627eb637eb4 documentation
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diff changeset
1837
5627eb637eb4 documentation
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diff changeset
1838
642
c4216a583de4 add links to functions in manual
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diff changeset
1839 <h4 heading><a name="Luan.assert" href="#Luan.assert"><code>Luan.assert (v [, message])</code></a></h4>
470
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diff changeset
1840
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diff changeset
1841 <p>
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diff changeset
1842 Could be defined as:
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diff changeset
1843
562
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diff changeset
1844 <pre>
470
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diff changeset
1845 function Luan.assert(v,message)
472
f4aca5a5346a minor documentation
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diff changeset
1846 return v or <a href="#Luan.error">Luan.error</a>(message or "assertion failed!")
470
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diff changeset
1847 end
562
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diff changeset
1848 </pre>
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diff changeset
1849
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diff changeset
1850
642
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diff changeset
1851 <h4 heading><a name="Luan.assert_binary" href="#Luan.assert_binary"><code>Luan.assert_binary (v)</code></a></h4>
470
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diff changeset
1852
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diff changeset
1853 <p>
5627eb637eb4 documentation
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diff changeset
1854 Could be defined as:
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diff changeset
1855
562
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diff changeset
1856 <pre>
470
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diff changeset
1857 function Luan.assert_binary(v)
5627eb637eb4 documentation
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parents: 469
diff changeset
1858 local v_type = Luan.type(v)
472
f4aca5a5346a minor documentation
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parents: 470
diff changeset
1859 return v_type == "binary" and v or <a href="#Luan.error">Luan.error</a>("bad argument #1 (binary expected, got "..v_type..")")
470
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diff changeset
1860 end
562
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diff changeset
1861 </pre>
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diff changeset
1862
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diff changeset
1863
642
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diff changeset
1864 <h4 heading><a name="Luan.assert_boolean" href="#Luan.assert_boolean"><code>Luan.assert_boolean (v)</code></a></h4>
562
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diff changeset
1865
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diff changeset
1866 <p>
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diff changeset
1867 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>boolean</code>.
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diff changeset
1868
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diff changeset
1869
642
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diff changeset
1870 <h4 heading><a name="Luan.assert_function" href="#Luan.assert_function"><code>Luan.assert_function (v)</code></a></h4>
626
53a50c70c5e2 add Luan.assert_function() and Http.run_later()
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parents: 604
diff changeset
1871
53a50c70c5e2 add Luan.assert_function() and Http.run_later()
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parents: 604
diff changeset
1872 <p>
53a50c70c5e2 add Luan.assert_function() and Http.run_later()
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parents: 604
diff changeset
1873 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>function</code>.
53a50c70c5e2 add Luan.assert_function() and Http.run_later()
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parents: 604
diff changeset
1874
53a50c70c5e2 add Luan.assert_function() and Http.run_later()
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parents: 604
diff changeset
1875
642
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diff changeset
1876 <h4 heading><a name="Luan.assert_integer" href="#Luan.assert_integer"><code>Luan.assert_integer (v)</code></a></h4>
562
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diff changeset
1877
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diff changeset
1878 <p>
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diff changeset
1879 Asserts that <code>v</code> can be converted to Java type <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html">Integer</a> and returns an Integer.
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diff changeset
1880
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diff changeset
1881
642
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diff changeset
1882 <h4 heading><a name="Luan.assert_long" href="#Luan.assert_long"><code>Luan.assert_long (v)</code></a></h4>
562
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diff changeset
1883
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diff changeset
1884 <p>
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diff changeset
1885 Asserts that <code>v</code> can be converted to Java type <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Long.html">Long</a> and returns a Long.
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diff changeset
1886
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diff changeset
1887
642
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diff changeset
1888 <h4 heading><a name="Luan.assert_number" href="#Luan.assert_number"><code>Luan.assert_number (v)</code></a></h4>
562
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diff changeset
1889
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diff changeset
1890 <p>
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diff changeset
1891 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>number</code>.
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diff changeset
1892
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diff changeset
1893
642
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diff changeset
1894 <h4 heading><a name="Luan.assert_string" href="#Luan.assert_string"><code>Luan.assert_string (v)</code></a></h4>
562
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diff changeset
1895
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diff changeset
1896 <p>
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diff changeset
1897 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>string</code>.
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diff changeset
1898
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parents: 556
diff changeset
1899
642
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diff changeset
1900 <h4 heading><a name="Luan.assert_table" href="#Luan.assert_table"><code>Luan.assert_table (v)</code></a></h4>
562
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diff changeset
1901
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diff changeset
1902 <p>
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diff changeset
1903 Like <a href="#Luan.assert_binary"><code>assert_binary</code></a> but for type <code>table</code>.
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diff changeset
1904
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parents: 556
diff changeset
1905
642
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diff changeset
1906 <h4 heading><a name="Luan.do_file" href="#Luan.do_file"><code>Luan.do_file ([uri])</code></a></h4>
470
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diff changeset
1907
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parents: 469
diff changeset
1908 <p>
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diff changeset
1909 Could be defined as:
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diff changeset
1910
562
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diff changeset
1911 <pre>
470
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parents: 469
diff changeset
1912 function Luan.do_file(uri)
474
00646edc9d92 documentation
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parents: 472
diff changeset
1913 return <a href="#Luan.load_file">Luan.load_file</a>(uri)()
470
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diff changeset
1914 end
562
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diff changeset
1915 </pre>
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parents: 556
diff changeset
1916
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parents: 556
diff changeset
1917
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diff changeset
1918
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diff changeset
1919 <h4 heading><a name="Luan.error" href="#Luan.error"><code>Luan.error (message)</code></a></h4>
470
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diff changeset
1920
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1921 <p>
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1922 Throws an error containing the message.
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1923
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1924 <p>
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1925 Could be defined as:
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1926
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1927 <pre>
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1928 function Luan.error(message)
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1929 <a href="#Luan.new_error">Luan.new_error</a>(message).throw()
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1930 end
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1931 </pre>
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1932
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1933
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1934
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1935 <h4 heading><a name="Luan.get_metatable" href="#Luan.get_metatable"><code>Luan.get_metatable (table)</code></a></h4>
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1936
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1937 <p>
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1938 If <code>table</code> does not have a metatable, returns <b>nil</b>.
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1939 Otherwise,
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1940 if the table's metatable has a <code>"__metatable"</code> field,
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1941 returns the associated value.
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1942 Otherwise, returns the metatable of the given table.
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1943
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1944
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1945 <h4 heading><a name="Luan.ipairs" href="#Luan.ipairs"><code>Luan.ipairs (t)</code></a></h4>
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1946
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1947 <p>
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1948 Returns an iterator function
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1949 so that the construction
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1950
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1951 <pre>
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1952 for i,v in ipairs(t) do <em>body</em> end
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1953 </pre>
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1954
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1955 <p>
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1956 will iterate over the key&ndash;value pairs
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1957 (<code>1,t[1]</code>), (<code>2,t[2]</code>), ...,
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1958 up to the first nil value.
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1959
474
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1960 <p>
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1961 Could be defined as:
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1962
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1963 <pre>
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1964 function Luan.ipairs(t)
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1965 local i = 0
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1966 return function()
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1967 if i < #t then
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1968 i = i + 1
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1969 return i, t[i]
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1970 end
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1971 end
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1972 end
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1973 </pre>
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1974
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1975
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1976
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1977 <h4 heading><a name="Luan.load" href="#Luan.load"><code>Luan.load (text, [source_name [env, [, allow_expression]]])</code></a></h4>
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1978
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1979 <p>
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1980 Loads a chunk.
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1981
474
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1982 <p>
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1983 The <code>text</code> is compiled.
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1984 If there are no syntactic errors,
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1985 returns the compiled chunk as a function;
474
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1986 otherwise, throws an error.
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1987
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1988 <p>
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1989 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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1990
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1991 <p>
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diff changeset
1992 If the <code>env</code> parameter is supplied, it becomes the <code>_ENV</code> of the chunk.
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1993
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diff changeset
1994 <p>
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diff changeset
1995 If the <code>allow_expression</code> parameter is <code>true</code> then the entire text can be nothing more than an expression in which case the chunk returns the value of this expression.
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1996
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diff changeset
1997
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1998 <h4 heading><a name="Luan.load_file" href="#Luan.load_file"><code>Luan.load_file (file_uri [, add_extension])</code></a></h4>
562
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1999
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diff changeset
2000 <p>
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diff changeset
2001 Similar to <a href="#Luan.load"><code>load</code></a>,
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2002 but gets the chunk from file <code>file_uri</code>
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2003 or from the standard input,
474
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2004 if no file uri is given.
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diff changeset
2005
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diff changeset
2006 <p>
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diff changeset
2007 Could be defined as:
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diff changeset
2008
562
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2009 <pre>
474
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diff changeset
2010 function Luan.load_file(file_uri,add_extension)
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diff changeset
2011 file_uri = file_uri or "stdin:"
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diff changeset
2012 local f = Io.uri(file_uri,add_extension)
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diff changeset
2013 f.exists() or <a href="#Luan.error">Luan.error</a>("file '"..file_uri.."' not found")
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diff changeset
2014 return <a href="#Luan.load">Luan.load</a>( f.read_text(), file_uri )
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2015 end
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2016 </pre>
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diff changeset
2017
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diff changeset
2018
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2019 <h4 heading><a name="Luan.new_error" href="#Luan.new_error"><code>Luan.new_error (message)</code></a></h4>
562
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2020
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diff changeset
2021 <p>
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diff changeset
2022 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
2023
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diff changeset
2024 <p>
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diff changeset
2025 To print the current stack trace, you could do:
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diff changeset
2026
562
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2027 <pre>
482
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diff changeset
2028 Io.print( Luan.new_error "stack" )
562
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diff changeset
2029 </pre>
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2030
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2031
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2032 <h4 heading><a name="Luan.pairs" href="#Luan.pairs"><code>Luan.pairs (t)</code></a></h4>
562
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diff changeset
2033
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diff changeset
2034 <p>
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diff changeset
2035 If <code>t</code> has a metamethod <code>__pairs</code>,
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diff changeset
2036 calls it with <code>t</code> as argument and returns the
475
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diff changeset
2037 result from the call.
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2038
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diff changeset
2039
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diff changeset
2040 <p>
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2041 Otherwise,
475
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diff changeset
2042 returns a function
371
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2043 so that the construction
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2044
562
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diff changeset
2045 <pre>
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diff changeset
2046 for k,v in pairs(t) do <em>body</em> end
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diff changeset
2047 </pre>
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diff changeset
2048
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diff changeset
2049 <p>
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diff changeset
2050 will iterate over all key&ndash;value pairs of table <code>t</code>.
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diff changeset
2051
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diff changeset
2052
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diff changeset
2053
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diff changeset
2054 <h4 heading><a name="Luan.pcall" href="#Luan.pcall"><code>Luan.pcall (f [, arg1, &middot;&middot;&middot;])</code></a></h4>
562
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diff changeset
2055
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diff changeset
2056 <p>
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diff changeset
2057 Calls function <code>f</code> with
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diff changeset
2058 the given arguments in <em>protected mode</em>.
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diff changeset
2059 This means that any error inside&nbsp;<code>f</code> is not propagated;
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diff changeset
2060 instead, <code>pcall</code> catches the error
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2061 and returns a status code.
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2062 Its first result is the status code (a boolean),
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2063 which is true if the call succeeds without errors.
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diff changeset
2064 In such case, <code>pcall</code> also returns all results from the call,
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2065 after this first result.
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diff changeset
2066 In case of any error, <code>pcall</code> returns <b>false</b> plus the error.
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2067
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2068
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diff changeset
2069
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2070
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2071 <p>
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diff changeset
2072 <hr><h3><a name="pdf-print"><code>print (&middot;&middot;&middot;)</code></a></h3>
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2073 Receives any number of arguments
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parents:
diff changeset
2074 and prints their values to <code>stdout</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2075 using the <a href="#pdf-tostring"><code>tostring</code></a> function to convert each argument to a string.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2076 <code>print</code> is not intended for formatted output,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2077 but only as a quick way to show a value,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2078 for instance for debugging.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2079 For complete control over the output,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2080 use <a href="#pdf-string.format"><code>string.format</code></a> and <a href="#pdf-io.write"><code>io.write</code></a>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2081
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2083
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2084 <h4 heading><a name="Luan.range" href="#Luan.range"><code>Luan.range (start, stop [, step])</code></a></h4>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2085
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2086 <p>
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2087 Based on <a href="https://docs.python.org/2/library/functions.html#range">the Python range() function</a>, this lets one iterate through a sequence of numbers.
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2088
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2089 <p>
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2090 Example use:
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2091
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2092 <pre>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2093 for i in range(1,10) do
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2094 Io.print("count up:",i)
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2095 end
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2096 for i in range(10,0,-1) do
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2097 Io.print("count down:",i)
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2098 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2099 </pre>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2100
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2101 <p>
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2102 Could be defined as:
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2103
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2104 <pre>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2105 function Luan.range(start, stop, step)
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2106 step = step or 1
478
eb6d90fb0b5c documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 476
diff changeset
2107 step == 0 and <a href="#Luan.error">Luan.error</a> "bad argument #3 (step may not be zero)"
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2108 local i = start
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2109 return function()
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2110 if step > 0 and i <= stop or step < 0 and i >= stop then
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2111 local rtn = i
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2112 i = i + step
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2113 return rtn
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2114 end
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2115 end
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2116 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2117 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2118
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2119
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2120
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2121 <h4 heading><a name="Luan.raw_equal" href="#Luan.raw_equal"><code>Luan.raw_equal (v1, v2)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2122
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2123 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2124 Checks whether <code>v1</code> is equal to <code>v2</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2125 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2126 Returns a boolean.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2127
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2128
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2129
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2130 <h4 heading><a name="Luan.raw_get" href="#Luan.raw_get"><code>Luan.raw_get (table, index)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2131
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2132 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2133 Gets the real value of <code>table[index]</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2134 without invoking any metamethod.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2135 <code>table</code> must be a table;
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2136 <code>index</code> may be any value.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2137
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2138
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2139
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2140 <h4 heading><a name="Luan.raw_len" href="#Luan.raw_len"><code>Luan.raw_len (v)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2141
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2142 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2143 Returns the length of the object <code>v</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2144 which must be a table or a string,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2145 without invoking any metamethod.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2146 Returns an integer.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2147
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2148
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2149
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2150 <h4 heading><a name="Luan.raw_set" href="#Luan.raw_set"><code>Luan.raw_set (table, index, value)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2151
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2152 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2153 Sets the real value of <code>table[index]</code> to <code>value</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2154 without invoking any metamethod.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2155 <code>table</code> must be a table,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2156 <code>index</code> any value different from <b>nil</b>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2157 and <code>value</code> any Lua value.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2158
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2159
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2160 <h4 heading><a name="Luan.set_metatable" href="#Luan.set_metatable"><code>Luan.set_metatable (table, metatable)</code></a></h4>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2161
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2162 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2163 Sets the metatable for the given table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2164 If <code>metatable</code> is <b>nil</b>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2165 removes the metatable of the given table.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2166 If the original metatable has a <code>"__metatable"</code> field,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2167 raises an error.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2168
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2169
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2170
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2171 <h4 heading><a name="Luan.to_string" href="#Luan.to_string"><code>Luan.to_string (v)</code></a></h4>
475
7ac0891718eb documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 474
diff changeset
2172
7ac0891718eb documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 474
diff changeset
2173 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2174 Receives a value of any type and
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2175 converts it to a string in a human-readable format.
475
7ac0891718eb documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 474
diff changeset
2176
7ac0891718eb documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 474
diff changeset
2177 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2178 If the metatable of <code>v</code> has a <code>"__to_string"</code> field,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2179 then <code>to_string</code> calls the corresponding value
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2180 with <code>v</code> as argument,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2181 and uses the result of the call as its result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2182
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2183
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2184
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2185 <h4 heading><a name="Luan.try" href="#Luan.try"><code>Luan.try (t, &middot;&middot;&middot;)</code></a></h4>
589
97c8ae330efe add varargs to Luan.try;
Franklin Schmidt <fschmidt@gmail.com>
parents: 581
diff changeset
2186
97c8ae330efe add varargs to Luan.try;
Franklin Schmidt <fschmidt@gmail.com>
parents: 581
diff changeset
2187 <p>
97c8ae330efe add varargs to Luan.try;
Franklin Schmidt <fschmidt@gmail.com>
parents: 581
diff changeset
2188 Implements try-catch as found in other languages where each block is in table <code>t</code>. <code>t[1]</code> is the "try" block. The <code>t.catch</code> and <code>t.finally</code> blocks are optional. Any extra arguments are passed to the "try" function. Returns the result of the "try" block or the "catch" block.
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2189
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2190 <p>
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2191 Example use:
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2192
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2193 <pre>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2194 try {
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2195 function()
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2196 a_dangerous_fn()
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2197 end;
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2198 catch = function(e)
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2199 -- handle error
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2200 end;
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2201 finally = function()
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2202 -- clean up
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2203 end;
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2204 }
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2205 </pre>
476
cd22e4694ea3 documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 475
diff changeset
2206
482
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2207 <p>
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2208 Could be defined as:
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2209
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2210 <pre>
482
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2211 function Luan.try(t)
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2212 local r = { <a href="#Luan.pcall">Luan.pcall</a>(t[1]) }
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2213 if r[1] then
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2214 Table.remove(r,1)
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2215 elseif t.catch ~= nil then
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2216 r = { t.catch(r[2]) }
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2217 else
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2218 t.finally and t.finally()
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2219 r[2].throw()
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2220 end
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2221 t.finally and t.finally()
7e9fcfbf22ec documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 479
diff changeset
2222 return Table.unpack(r)
7e9fcfbf22ec documentation
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parents: 479
diff changeset
2223 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2224 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2225
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2226
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2227 <h4 heading><a name="Luan.type" href="#Luan.type"><code>Luan.type (v)</code></a></h4>
475
7ac0891718eb documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 474
diff changeset
2228
7ac0891718eb documentation
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parents: 474
diff changeset
2229 <p>
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2230 Returns the type of its only argument, coded as a string.
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2231 The possible results of this function are
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2232 "<code>nil</code>" (a string, not the value <b>nil</b>),
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diff changeset
2233 "<code>number</code>",
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diff changeset
2234 "<code>string</code>",
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diff changeset
2235 "<code>binary</code>",
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diff changeset
2236 "<code>boolean</code>",
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diff changeset
2237 "<code>table</code>",
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diff changeset
2238 "<code>function</code>",
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diff changeset
2239 and "<code>java</code>".
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diff changeset
2240
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diff changeset
2241
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diff changeset
2242 <h4 heading><a name="Luan.values" href="#Luan.values"><code>Luan.values (&middot;&middot;&middot;)</code></a></h4>
476
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2243
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2244 <p>
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2245 Returns a function so that the construction
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2246
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2247 <pre>
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2248 for v in Luan.values(&middot;&middot;&middot;) do <em>body</em> end
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2249 </pre>
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diff changeset
2250
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2251 <p>
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diff changeset
2252 will iterate over all values of <code>&middot;&middot;&middot;</code>.
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2253
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diff changeset
2254
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diff changeset
2255
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diff changeset
2256 <h4 heading><a name="Luan.VERSION" href="#Luan.VERSION"><code>Luan.VERSION</code></a></h4>
475
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diff changeset
2257
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diff changeset
2258 <p>
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diff changeset
2259 A global variable (not a function) that
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2260 holds a string containing the current interpreter version.
562
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diff changeset
2261 The current value of this variable is "<code><%=Luan.VERSION%></code>".
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diff changeset
2262
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diff changeset
2263
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diff changeset
2264
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diff changeset
2265
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diff changeset
2266
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diff changeset
2267
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diff changeset
2268 <h3 heading><a name="package_lib">Modules</a></h3>
476
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diff changeset
2269
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diff changeset
2270 <p>
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diff changeset
2271 Include this library by:
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diff changeset
2272
562
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diff changeset
2273 <pre>
476
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diff changeset
2274 local Package = require "luan:Package"
562
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diff changeset
2275 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2276
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2277 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2278 The package library provides basic
476
cd22e4694ea3 documentation
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diff changeset
2279 facilities for loading modules in Luan.
cd22e4694ea3 documentation
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diff changeset
2280
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diff changeset
2281
642
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diff changeset
2282 <h4 heading><a name="Package.load" href="#Package.load"><code>Package.load (mod_uri)</code></a></h4>
371
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diff changeset
2283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2285 Loads the given module.
562
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diff changeset
2286 The function starts by looking into the <a href="#Package.loaded"><code>Package.loaded</code></a> table
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diff changeset
2287 to determine whether <code>mod_uri</code> is already loaded.
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diff changeset
2288 If it is, then <code>Package.load</code> returns the value stored
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diff changeset
2289 at <code>Package.loaded[mod_uri]</code>.
476
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diff changeset
2290 Otherwise, it tries to load a new value for the module.
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diff changeset
2291
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diff changeset
2292 <p>
562
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diff changeset
2293 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
2294
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diff changeset
2295 <p>
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diff changeset
2296 If <code>mod_uri</code> is not a Java class, then <code>Package.load</code> tries to read the text of the file referred to by <code>mod_uri</code> (using <code>add_extension</code>=true). If the file doesn't exist, then <code>Package.load</code> returns <b>nil</b>. If the file exists, then its content is compiled into a chunk calling <a href="#Luan.load"><code>Luan.load</code></a> and passing in an empty table as the <code>env</code> value. This chunk is run passing in <code>mod_uri</code> as an argument. If the chunk returns a value other than <b>nil</b>, then that value is the value of this module. Otherwise the <code>env</code> that was passed in is the value of this module.
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diff changeset
2297
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diff changeset
2298 <p>
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diff changeset
2299 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
2300
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diff changeset
2301
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diff changeset
2302
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diff changeset
2303
642
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diff changeset
2304 <h4 heading><a name="Package.loaded" href="#Package.loaded"><code>Package.loaded</code></a></h4>
562
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diff changeset
2305
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diff changeset
2306
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diff changeset
2307 <p>
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diff changeset
2308 A table used by <a href="#Package.load"><code>Package.load</code></a> to control which
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2309 modules are already loaded.
562
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diff changeset
2310 When you load a module <code>mod_uri</code> and
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diff changeset
2311 <code>Package.loaded[mod_uri]</code> is not <b>nil</b>,
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diff changeset
2312 <a href="#Package.load"><code>Package.load</code></a> simply returns the value stored there.
371
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diff changeset
2313
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2314
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2315 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2316 This variable is only a reference to the real table;
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diff changeset
2317 assignments to this variable do not change the
562
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diff changeset
2318 table used by <a href="#Package.load"><code>Package.load</code></a>.
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diff changeset
2319
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diff changeset
2320
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diff changeset
2321
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diff changeset
2322
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diff changeset
2323
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diff changeset
2324
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diff changeset
2325 <h3 heading><a name="string_lib">String Manipulation</a></h3>
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2326
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diff changeset
2327 <p>
e25ba7a2e816 some String documentation and fixes
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diff changeset
2328 Include this library by:
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diff changeset
2329
562
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diff changeset
2330 <pre>
555
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diff changeset
2331 local String = require "luan:String"
562
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diff changeset
2332 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2333
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diff changeset
2334 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2335 This library provides generic functions for string manipulation,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2336 such as finding and extracting substrings, and pattern matching.
555
e25ba7a2e816 some String documentation and fixes
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diff changeset
2337 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
2338 (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
2339 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
2340 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
2341 Thus, the last character is at position -1, and so on.
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diff changeset
2342
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2343
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2344
642
c4216a583de4 add links to functions in manual
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diff changeset
2345 <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
2346
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diff changeset
2347 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
2348 Receives zero or more integers.
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diff changeset
2349 Returns a string with length equal to the number of arguments,
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diff changeset
2350 in which each character has the internal numerical code equal
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parents:
diff changeset
2351 to its corresponding argument.
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diff changeset
2352
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diff changeset
2353
642
c4216a583de4 add links to functions in manual
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diff changeset
2354 <h4 heading><a name="String.concat" href="#String.concat"><code>String.concat (&middot;&middot;&middot;)</code></a></h4>
562
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diff changeset
2355
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diff changeset
2356 <p>
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diff changeset
2357 Concatenates the <a href="#Luan.to_string"><code>to_string</code></a> value of all arguments.
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diff changeset
2358
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diff changeset
2359
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diff changeset
2360
642
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diff changeset
2361 <h4 heading><a name="String.encode" href="#String.encode"><code>String.encode (s)</code></a></h4>
562
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diff changeset
2362
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diff changeset
2363 <p>
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diff changeset
2364 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
2365
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diff changeset
2366
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diff changeset
2367
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diff changeset
2368
642
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diff changeset
2369 <h4 heading><a name="String.find" href="#String.find"><code>String.find (s, pattern [, init [, plain]])</code></a></h4>
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diff changeset
2370
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diff changeset
2371 <p>
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diff changeset
2372 Looks for the first match of
562
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diff changeset
2373 <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) in the string <code>s</code>.
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diff changeset
2374 If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
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diff changeset
2375 where this occurrence starts and ends;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2376 otherwise, it returns <b>nil</b>.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2377 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
2378 where to start the search;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2379 its default value is&nbsp;1 and can be negative.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2380 A value of <b>true</b> as a fourth, optional argument <code>plain</code>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2381 turns off the pattern matching facilities,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2382 so the function does a plain "find substring" operation,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2383 with no characters in <code>pattern</code> being considered magic.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2384 Note that if <code>plain</code> is given, then <code>init</code> must be given as well.
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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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 pattern has captures,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2388 then in a successful match
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2389 the captured values are also returned,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2390 after the two indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2391
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2392
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2395 <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
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2396
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2397
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2398 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2399 Returns a formatted version of its variable number of arguments
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2400 following the description given in its first argument (which must be a string).
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2401 The format string follows the same rules as the Java function <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#format(java.lang.String,%20java.lang.Object...)"><code>String.format</code></a> because Luan calls this internally.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2402
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2403 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2404 Note that Java's <code>String.format</code> is too stupid to convert between ints and floats, so you must provide the right kind of number.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2405
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2406
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2407
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2408 <h4 heading><a name="String.gmatch" href="#String.gmatch"><code>String.gmatch (s, pattern)</code></a></h4>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2409
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2410 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2411 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
2412 each time it is called,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2413 returns the next captures from <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>)
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2414 over the string <code>s</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2415 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
2416 then the whole match is produced in each call.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2417
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2418
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2419 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2420 As an example, the following loop
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2421 will iterate over all the words from string <code>s</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2422 printing one per line:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2423
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2424 <pre>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2425 local s = "hello world from Lua"
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2426 for w in String.gmatch(s, [[\w+]]) do
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2427 print(w)
e25ba7a2e816 some String documentation and fixes
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parents: 553
diff changeset
2428 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2429 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2430
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2431 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2432 The next example collects all pairs <code>key=value</code> from the
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2433 given string into a table:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2434
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2435 <pre>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2436 local t = {}
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2437 local s = "from=world, to=Lua"
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2438 for k, v in String.gmatch(s, [[(\w+)=(\w+)]]) do
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2439 t[k] = v
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2440 end
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2441 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2442
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2443 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2444 For this function, a caret '<code>^</code>' at the start of a pattern does not
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2445 work as an anchor, as this would prevent the iteration.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2447
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2448
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2449 <h4 heading><a name="String.gsub" href="#String.gsub"><code>String.gsub (s, pattern, repl [, n])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2450
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2451 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2452 Returns a copy of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2453 in which all (or the first <code>n</code>, if given)
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2454 occurrences of the <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) have been
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2455 replaced by a replacement string specified by <code>repl</code>,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2456 which can be a string, a table, or a function.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2457 <code>gsub</code> also returns, as its second value,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2458 the total number of matches that occurred.
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2459 The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2460
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2461
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2462 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2463 If <code>repl</code> is a string, then its value is used for replacement.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2464 The character&nbsp;<code>\</code> works as an escape character.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2465 Any sequence in <code>repl</code> of the form <code>$<em>d</em></code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2466 with <em>d</em> between 1 and 9,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2467 stands for the value of the <em>d</em>-th captured substring.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2468 The sequence <code>$0</code> stands for the whole match.
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2469
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2470
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 If <code>repl</code> is a table, then the table is queried for every match,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2473 using the first capture as the key.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2474
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2475
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2476 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2477 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
2478 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
2479 in order.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2481
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2482 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2483 In any case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2484 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
2485 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
2486
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2487
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2488 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2489 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
2490 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
2491 then it is used as the replacement string;
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2492 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
2493 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
2494 (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
2495
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2498 Here are some examples:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2499
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2500 <pre>
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2501 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
2502 --&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
2503
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2504 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
2505 --&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
2506
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2507 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
2508 --&gt; x="world hello Luan from"
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2509
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2510 x = String.gsub("4+5 = $return 4+5$", [[\$(.*?)\$]], function (s)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2511 return load(s)()
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2512 end)
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2513 --&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
2514
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2515 local t = {name="lua", version="5.3"}
555
e25ba7a2e816 some String documentation and fixes
Franklin Schmidt <fschmidt@gmail.com>
parents: 553
diff changeset
2516 x = String.gsub("$name-$version.tar.gz", [[\$(\w+)]], t)
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2517 --&gt; x="lua-5.3.tar.gz"
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2518 </pre>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2519
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2520
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2521
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2522 <h4 heading><a name="String.literal" href="#String.literal"><code>String.literal (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2523 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2524 Returns a string which matches the literal string <code>s</code> in a regular expression. This function is simply the Java method <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html#quote(java.lang.String)"><code>Pattern.quote</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2525
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2526
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2527 <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
2528 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2529 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
2530 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
2531 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
2532
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2533
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2534
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2535
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2536 <h4 heading><a name="String.match" href="#String.match"><code>String.match (s, pattern [, init])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2537
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2538 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2539 Looks for the first <em>match</em> of
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2540 <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
2541 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
2542 the captures from the pattern;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2543 otherwise it returns <b>nil</b>.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2544 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
2545 then the whole match is returned.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2546 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
2547 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
2548 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
2549
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2550
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2551 <h4 heading><a name="String.matches" href="#String.matches"><code>String.matches (s, pattern)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2552 <p>
629
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2553 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
2554 This function is equivalent to
35dde32c02ab change String.matches()
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parents: 626
diff changeset
2555
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2556 <pre>
35dde32c02ab change String.matches()
Franklin Schmidt <fschmidt@gmail.com>
parents: 626
diff changeset
2557 return String.match(s,pattern) ~= nil
35dde32c02ab change String.matches()
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parents: 626
diff changeset
2558 </pre>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2559
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2560
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2561 <h4 heading><a name="String.rep" href="#String.rep"><code>String.rep (s, n [, sep])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2562 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2563 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
2564 the string <code>s</code> separated by the string <code>sep</code>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2565 The default value for <code>sep</code> is the empty string
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2566 (that is, no separator).
562
7cc9d4a53d3b remove SimplyHTML from documentation
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diff changeset
2567 Returns the empty string if <code>n</code> is not positive.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2568
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2569
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2570
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2571
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2572 <h4 heading><a name="String.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
2573 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2574 Returns a string that is the string <code>s</code> reversed.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2575
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2576
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2577
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2578
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2579 <h4 heading><a name="String.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
2580
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2581 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2582 Returns the substring of <code>s</code> that
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2583 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
2584 <code>i</code> and <code>j</code> can be negative.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2585 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
2586 (which is the same as the string length).
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
2587 In particular,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2588 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
2589 with length <code>j</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2590 and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2591 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
2592
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2593
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2594 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2595 If, after the translation of negative indices,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2596 <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
2597 it is corrected to 1.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2598 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
2599 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
2600 If, after these corrections,
562
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2601 <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
2602 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
2603
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2604
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2605
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2606 <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
2607
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2608 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2609 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
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parents: 556
diff changeset
2610
7cc9d4a53d3b remove SimplyHTML from documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2611
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2612
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2613 <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
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parents: 556
diff changeset
2614
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2615 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2616 When called with no <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2617 <code>to_number</code> tries to convert its argument to a number.
556
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2618 If the argument is
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2619 a string convertible to a number,
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2620 then <code>to_number</code> returns this number;
556
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2621 otherwise, it returns <b>nil</b>.
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2622
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2623 The conversion of strings can result in integers or floats.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2624
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2625
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2626 <p>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2627 When called with <code>base</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2628 then <code>s</code> must be a string to be interpreted as
556
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2629 an integer numeral in that base.
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2630 In bases above&nbsp;10, the letter '<code>A</code>' (in either upper or lower case)
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2631 represents&nbsp;10, '<code>B</code>' represents&nbsp;11, and so forth,
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Franklin Schmidt <fschmidt@gmail.com>
parents: 556
diff changeset
2632 with '<code>Z</code>' representing 35.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2633 If the string <code>s</code> is not a valid numeral in the given base,
556
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2634 the function returns <b>nil</b>.
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2635
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2636
d02f43598ba3 finish String documentation
Franklin Schmidt <fschmidt@gmail.com>
parents: 555
diff changeset
2637
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2638 <h4 heading><a name="String.trim" href="#String.trim"><code>String.trim (s)</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2639
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2640 <p>
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2641 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
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parents: 556
diff changeset
2642
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2643
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2644
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2645
642
c4216a583de4 add links to functions in manual
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parents: 629
diff changeset
2646 <h4 heading><a name="String.unicode" href="#String.unicode"><code>String.unicode (s [, i [, j]])</code></a></h4>
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2647
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2648 <p>
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parents: 556
diff changeset
2649 Returns the internal numerical codes of the characters <code>s[i]</code>,
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2650 <code>s[i+1]</code>, ..., <code>s[j]</code>.
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parents: 556
diff changeset
2651 The default value for <code>i</code> is&nbsp;1;
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2652 the default value for <code>j</code> is&nbsp;<code>i</code>.
556
d02f43598ba3 finish String documentation
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parents: 555
diff changeset
2653 These indices are corrected
562
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2654 following the same rules of function <a href="#String.sub"><code>String.sub</code></a>.
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2655
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2656
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2657
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2658
7cc9d4a53d3b remove SimplyHTML from documentation
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parents: 556
diff changeset
2659
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2660 <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
2661 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2662 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
2663 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
2664 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
2665 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
2666
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2667
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2668
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2669
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2670
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2671 <h3 heading><a name="binary_lib">Binary Manipulation</a></h3>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2672
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2673 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2674 Include this library by:
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2675
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2676 <pre>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2677 local Binary = require "luan:Binary"
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2678 </pre>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2679
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2680
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2681 <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
2682
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2683 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2684 Receives zero or more bytes (as integers).
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2685 Returns a binary with length equal to the number of arguments,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2686 in which each byte has the internal numerical code equal
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2687 to its corresponding argument.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2688
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2689
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2690 <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
2691
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2692 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2693 Returns the internal numerical codes of the bytes <code>b[i]</code>,
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2694 <code>b[i+1]</code>, ..., <code>b[j]</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2695 The default value for <code>i</code> is&nbsp;1;
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2696 the default value for <code>j</code> is&nbsp;<code>i</code>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2697 These indices are corrected
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2698 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
2699
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2700
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2701 <h4 heading><a name="Binary.to_string" href="#Binary.to_string"><code>Binary.to_string (b)</code></a></h4>
567
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2702 <p>
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2703 Converts the binary <code>b</code> to a string using the Java <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#String(byte[])">String constructor</a>.
6c00b8a59240 document Binary
Franklin Schmidt <fschmidt@gmail.com>
parents: 566
diff changeset
2704
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2705
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2706
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2707
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2708 <h3 heading><a name="table_lib">Table Manipulation</a></h3>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2709
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2710 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2711 Include this library by:
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2712
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2713 <pre>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2714 local Table = require "luan:Table"
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2715 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2716
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2717 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2718 This library provides generic functions for table manipulation.
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2719 It provides all its functions inside the table <code>Table</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2720
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2721
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2722
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2723 <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
2724
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2725 <p>
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2726 Clears the table.
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2727
1e69d9c21461 add Table.clear();
Franklin Schmidt <fschmidt@gmail.com>
parents: 567
diff changeset
2728
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2729 <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
2730
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2731 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2732 Given a list,
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2733 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
2734 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
2735 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
2736 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
2737 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
2738
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2739
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2740 <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
2741
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2742 <p>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2743 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
2744 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
2745 By default, <code>j</code> is <code>#tbl</code>.
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2746
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2747
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2748
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2749 <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
2750
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2751 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2752 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
2753 shifting up the elements
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2754 <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
2755
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2756
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2757
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2758 <h4 heading><a name="Table.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
2759
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2760 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2761 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
2762 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
2763 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
2764
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2765
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2766
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2767
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2768 <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
2769
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2770
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2771 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2772 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
2773 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
2774 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
2775 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
2776 <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
2777 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
2778 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
2779 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
2780 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
2781
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2782
565
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2783
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2784
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2785 <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
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 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
2789 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
2790 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
2791 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
2792 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
2793 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
2794 (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
2795 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
2796 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
2797
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2798 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2799 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
2800 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
2801 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
2802
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2803
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2804
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2805 <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
2806
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2807 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2808 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
2809 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
2810
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2811 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2812 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
2813 </pre>
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2814
22bfd8a2eaee do Table documentation;
Franklin Schmidt <fschmidt@gmail.com>
parents: 562
diff changeset
2815 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2816 By default, <code>i</code> is&nbsp;1 and <code>j</code> is <code>#list</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2817
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2818
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2819
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2820
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2821 <h3 heading><a name="number_lib">Number Manipulation</a></h3>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2822
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2823 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2824 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2825
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2826 <pre>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2827 local Number = require "luan:Number"
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2828 </pre>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2829
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2830
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2831 <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
2832 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2833 Returns <code>x</code> as a double.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2834
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2835
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2836 <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
2837 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2838 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
2839 returns that integer.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2840 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2841
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2842
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2843 <h4 heading><a name="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
2844 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2845 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
2846 returns that long.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2847 Otherwise throws an error.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2848
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2849
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2850 <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
2851 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2852 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
2853
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2854
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2855 <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
2856 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2857 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
2858
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2859
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2860
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2861
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2862 <h3 heading><a name="math_lib">Mathematical Functions</a></h3>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2863
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2864 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2865 Include this library by:
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2866
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2867 <pre>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2868 local Math = require "luan:Math"
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2869 </pre>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2870
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2871 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2872 This library provides basic mathematical functions.
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2873 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
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.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
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 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
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2883 <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
2884
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2885 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2886 Returns the 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
2887
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2888
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2889
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2890
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2891 <h4 heading><a name="Math.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
2892
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2893 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2894 Returns the 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
2895
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2896
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2897
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2898
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2899 <h4 heading><a name="Math.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
2900
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2901 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2902 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
2903 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
2904 quadrant of the result.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2905 (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
2906
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2907
566
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2908
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
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.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
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 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
2914
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2915
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2916
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2917
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2918 <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
2919
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2920 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2921 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
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.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
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 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
2930
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2931
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2932
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
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.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
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 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
2938 (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
2939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2940
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2941
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2942
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2943 <h4 heading><a name="Math.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
2944
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2945 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2946 Returns the 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
2947
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2948
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2949
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2950
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2951 <h4 heading><a name="Math.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
2952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2953 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2954 Returns the 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
2955 that rounds the quotient towards zero.
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2956
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2957
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2958
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2959
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2960 <h4 heading><a name="Math.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
2961
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2962 <p>
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2963 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
2964
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2965
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2966
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2967
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2968 <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
2969
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2970 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2971 Returns the 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
2972 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
2973 (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
2974
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2975
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
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2978 <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
2979
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2980 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2981 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
2982 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
2983
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2984
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2985
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
2986
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2987 <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
2988 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2989 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
2990
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2991
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2992
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2993
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
2994 <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
2995
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2996 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
2997 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
2998 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
2999
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3000
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3001
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3002
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3003 <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
3004 <p>
371
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3005 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
3006
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3007
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3008
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3009
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3010 <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
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 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
3014
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3015
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3016
90b93790c544 Number and Math documentation and minor changes
Franklin Schmidt <fschmidt@gmail.com>
parents: 565
diff changeset
3017
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3018 <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
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 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
3022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3023
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3024
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3025
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3026 <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
3027
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3028 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3029 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
3030
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3031
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3032
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3033
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3034 <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
3035
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3036
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3037 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3038 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3039 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
3040 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
3041 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
3042 <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
3043 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
3044 (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
3045 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
3046
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3047
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3048 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3049 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
3050 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
3051 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
3052
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3053
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3055
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3056 <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
3057
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3058 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3059 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
3060
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3061
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3062
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3063
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3064 <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
3065
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3066 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3067 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
3068 (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
3069
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3070
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3072
642
c4216a583de4 add links to functions in manual
Franklin Schmidt <fschmidt@gmail.com>
parents: 629
diff changeset
3073 <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
3074
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3075 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3076 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3082
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3083
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3084
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3085 <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
3086
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3087 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3088 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
3089 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
3090 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
3091 default output file,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3092 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
3093 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
3094
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3095
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3096 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3097 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
3098 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
3099 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
3100 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
3101 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
3102
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3103
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3104 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3105 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
3106 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
3107 <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
3108 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
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 Unless otherwise stated,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3113 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
3114 (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
3115 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
3116 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
3117 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3118 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
3119 in case of errors
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3120 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
3121 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
3122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3123
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3124 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3125 <hr><h3><a name="pdf-io.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
3126
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3127
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3128 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3129 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
3130 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
3131
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3132
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3133
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3134
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3135 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3136 <hr><h3><a name="pdf-io.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
3137
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3138
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3139 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3140 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
3141
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3142
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3143
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3146 <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
3147
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3148
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3149 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3150 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
3151 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
3152 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
3153 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
3154 When called without parameters,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3155 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
3156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3157
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3158 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3159 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
3160 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
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.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
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 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
3171 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
3172 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
3173 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
3174 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
3175
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3176
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3177 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3178 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
3179 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
3180 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
3181 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
3182
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3185 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
3186 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
3187
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3188
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3190
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3191 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3192 <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
3193
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3194
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3195 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3196 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
3197 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
3198 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
3199 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
3200
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3201
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3202 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3203 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
3204
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3205 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3206 <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
3207 <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
3208 <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
3209 <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
3210 <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
3211 <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
3212 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
3213 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3214 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
3215 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
3216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3217
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3218
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3219
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3220 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3221 <hr><h3><a name="pdf-io.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
3222
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3223
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3224 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3225 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3230 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3231 <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
3232
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3233
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3234 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3235 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
3236 on all platforms.
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 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
3241 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
3242 (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
3243 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
3244 (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
3245
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3246
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3247
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3248
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3249 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3250 <hr><h3><a name="pdf-io.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
3251
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3252
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3253 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3254 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
3255
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3256
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3257
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3260 <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
3261
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3262
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3263 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3264 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
3265 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
3266 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
3267
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3268
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 <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
3273
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3274
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3275 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3276 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
3277 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
3278 <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
3279 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
3280
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3281
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3282
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3285 <hr><h3><a name="pdf-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
3286
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3287
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3288 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3289 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
3290
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3291
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3292
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3293
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3294 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3295 <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
3296
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3297
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3298 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3299 Closes <code>file</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3300 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
3301 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
3302 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
3303
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3304
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3305 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3306 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
3307 <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
3308 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
3309
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3310
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3311
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3312
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3313 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3314 <hr><h3><a name="pdf-file: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
3315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3317 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3318 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
3319
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3320
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3321
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3322
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3323 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3324 <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
3325
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3326
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3327 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3328 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
3329 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
3330 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
3331 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
3332 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
3333 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
3334
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3335 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3336 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
3337 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3338 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
3339 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
3340 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
3341 when the loop ends.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3342
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3345 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
3346 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
3347
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3348
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3351 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3352 <hr><h3><a name="pdf-file: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
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 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
3357 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
3358 For each format,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3359 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
3360 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
3361 (In this latter case,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3362 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
3363 When called without formats,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3364 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
3365 (see below).
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 The available formats are
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 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3372
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3373 <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
3374 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
3375 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
3376 (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
3377 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
3378 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
3379 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
3380 (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
3381 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
3382 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3383
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3384 <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
3385 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
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>a</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3389 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
3390 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
3391 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3392
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3393 <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
3394 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
3395 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
3396 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
3397 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3398
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3399 <li><b>"<code>L</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3400 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
3401 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
3402 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3403
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3404 <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
3405 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
3406 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
3407 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
3408 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
3409 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
3410 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3411
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3412 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3413 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3419 <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
3420
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3421
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3422 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3423 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
3424 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
3425 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
3426 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
3427
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3428 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3429 <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
3430 <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
3431 <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
3432 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3433 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
3434 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
3435 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
3436 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
3437
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3438
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3439 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3440 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
3441 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
3442 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
3443 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
3444 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
3445 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
3446 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
3447 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
3448
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3449
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3450
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3451
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3452 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3453 <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
3454
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3455
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3456 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3457 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
3458 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
3459
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3460 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3461
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3462 <li><b>"<code>no</code>": </b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3463 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
3464 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3465
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3466 <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
3467 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
3468 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
3469 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
3470 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3472 <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
3473 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
3474 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
3475 (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
3476 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3477
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3478 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3479 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
3480 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
3481 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
3482
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3483
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3484
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3485
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3486 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3487 <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
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 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
3492 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
3493
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3494
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3495 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3496 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
3497 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
3498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3499
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3500
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3505 <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
3506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3507 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3508 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
3509
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3511 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3512 <hr><h3><a name="pdf-os.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
3513
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3514
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3515 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3516 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
3517 used by the program.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3518
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3520
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3521
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3522 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3523 <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
3524
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3525
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3526 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3527 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
3528 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
3529
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3530
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3531 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3532 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
3533 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
3534 (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
3535 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3539 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
3540 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
3541 After this optional character,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3542 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
3543 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
3544 <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
3545 <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
3546 <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
3547 <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
3548 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
3549 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
3550 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
3551
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3554 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
3555 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
3556 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3560 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3561 <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
3562 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
3563 (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
3564
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3565
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3566 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3567 On non-POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3568 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
3569 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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3573
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3574 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3575 <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
3576
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3577
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3578 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3579 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
3580 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
3581 (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
3582 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
3583 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
3584
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3585
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3586
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3587
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3588 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3589 <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
3590
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3591
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3592 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3593 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
3594 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
3595 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
3596 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
3597 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
3598 After this first result
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3599 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
3600 as follows:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3601
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3602 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3603
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3604 <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
3605 the command terminated normally;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3606 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
3607 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3608
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3609 <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
3610 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
3611 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
3612 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3613
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3614 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3615
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3616 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3617 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
3618 <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
3619
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3620
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3621
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3622
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3623 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3624 <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
3625
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3626
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3627 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3628 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
3629 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
3630 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
3631 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
3632 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
3633 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
3634 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
3635 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
3636
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3637
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3638 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3639 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
3640 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
3641
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3642
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3643
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3644
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3645 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3646 <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
3647
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3648
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3649 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3650 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
3651 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
3652
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3653
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3654
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3655
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3656 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3657 <hr><h3><a name="pdf-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
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 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
3662 with the given name.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3663 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
3664 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
3665
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3666
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3667
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3668
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3669 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3670 <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
3671
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3672
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3673 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3674 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
3675 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
3676 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
3677
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3678
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 <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
3683
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3684
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3685 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3686 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
3687 <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
3688 <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
3689 <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
3690 <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
3691 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
3692 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
3693 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
3694
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3695
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3696 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3697 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
3698 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
3699 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
3700 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
3701
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3702
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3703 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3704 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
3705 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
3706 for the given category.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3707
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3708
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3709 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3710 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
3711 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
3712
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3713
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3714
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3715
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3716 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3717 <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
3718
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3721 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
3722 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
3723 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
3724 and may have fields
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3725 <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
3726 <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
3727 <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
3728 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
3729 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
3730
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3731
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3732 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3733 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
3734 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
3735 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
3736 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
3737 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
3738 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
3739 <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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3743
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3744 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3745 <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
3746
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3747
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3748 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3749 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
3750 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
3751 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
3752 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
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 On POSIX systems,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3757 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
3758 to avoid security risks.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3759 (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
3760 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
3761 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
3762 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
3763
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3764
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3765 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3766 When possible,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3767 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
3768 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
3769
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3770
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3771
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3772
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3773
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3774
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3775
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3776 <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
3777
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3778 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3779 This library provides
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3780 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
3781 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
3782 Several of its functions
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3783 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
3784 (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
3785 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
3786 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
3787 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
3788 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
3789 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3793 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
3794 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
3795 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
3796 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
3797 thread to operate over.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3798 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
3799
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3800
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3801 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3802 <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
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 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
3807 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
3808 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
3809 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
3810 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
3811 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
3812 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
3813
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3814
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3815 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3816 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
3817 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
3818
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3819
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3820
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3821
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3822 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3823 <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
3824
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3825
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3826 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3827 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
3828 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
3829 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
3830 (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
3831
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3832
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3833
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3834
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 <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
3837
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3840 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
3841 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
3842 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
3843 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
3844 of the given thread:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3845 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
3846 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
3847 (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
3848 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3849 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
3850 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
3851
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3852
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3853 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3854 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
3855 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
3856 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
3857 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
3858 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3859 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
3860 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
3861 If present,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3862 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
3863 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
3864 valid lines.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3865
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3866
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3867 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3868 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
3869 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
3870 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
3871 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
3872 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
3873 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
3874
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3875
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3876
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3877
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3878 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3879 <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
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 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
3884 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
3885 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
3886 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
3887
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3888
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3889 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3890 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
3891 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
3892 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
3893 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
3894 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
3895 -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
3896 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
3897 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
3898 (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
3899
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3900
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3901 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3902 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
3903 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
3904 (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
3905 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
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 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
3910 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
3911
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3912
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3913
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3914
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3915 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3916 <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
3917
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3918
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3919 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3920 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
3921 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
3922
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3923
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3924
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3925
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3926 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3927 <hr><h3><a name="pdf-debug.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
3928
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3929
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3930 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3931 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
3932
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3933
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3934
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3935
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3936 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3937 <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
3938
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3939
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3940 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3941 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
3942 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
3943 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
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 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
3948 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
3949 (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
3950
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3951
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3952
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3953
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3954 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3955 <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
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 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
3960 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
3961 returns <b>nil</b>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3962
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3963
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3964
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3965
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3966 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3967 <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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3971 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
3972 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
3973 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
3974 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
3975 with the given meaning:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3976
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3977 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3978 <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
3979 <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
3980 <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
3981 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3982 Moreover,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3983 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
3984 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
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3988 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3989 <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
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 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
3994 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
3995 <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
3996 <code>"return"</code>,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3997 <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
3998 For line events,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
3999 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
4000 Inside a hook,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4001 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
4002 the running function
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4003 (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
4004 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
4005
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4006
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4007
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4008
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4009 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4010 <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
4011
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4012
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4013 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4014 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
4015 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
4016 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
4017 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
4018 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
4019 (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
4020 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
4021
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4022
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4023 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4024 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
4025 variable indices and names.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4026
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4027
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4028
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4029
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 <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
4032
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4035 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
4036 (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
4037 Returns <code>value</code>.
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
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 <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
4044
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4045
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4046 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4047 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
4048 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
4049 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
4050 with the given index.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4051 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
4052
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4053
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4054
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4055
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4056 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4057 <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
4058
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4059
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4060 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4061 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
4062 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
4063 <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
4064
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4065
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4066 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4067 Returns <code>udata</code>.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4068
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4069
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4070
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4071
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4072 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4073 <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
4074
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4075
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4076 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4077 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
4078 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
4079 Otherwise,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4080 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
4081 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
4082 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
4083 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
4084 to start the traceback
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4085 (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
4086
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4087
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4088
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4089
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4090 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4091 <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
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 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
4096 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
4097 from the given function.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4098
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4099
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4100 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4101 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
4102 closures share upvalues.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4103 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
4104 (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
4105 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
4106
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4107
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4108
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4109
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4110 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4111 <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
4112
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4113
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4114 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4115 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
4116 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
4117
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4118
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4119
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4120
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4121
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4122
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4123
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4124 <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
4125
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4126 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4127 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
4128 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
4129 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
4130 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
4131 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
4132 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
4133 The standalone interpreter includes
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4134 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
4135 Its usage is:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4136
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4137 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4138 lua [options] [script [args]]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4139 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4140 The options are:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4141
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4142 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4143 <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
4144 <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
4145 <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
4146 <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
4147 <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
4148 <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
4149 <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
4150 </ul><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4151 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
4152 When called without arguments,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4153 <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
4154 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
4155 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
4156
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4157
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4158 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4159 When called 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
4160 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
4161 (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
4162 before running any argument.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4163 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
4164 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
4165 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
4166
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4167
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4168 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4169 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
4170 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
4171 Lua also ignores
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4172 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
4173 setting the values of
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4174 <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
4175 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
4176
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4177
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4178 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4179 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
4180 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
4181
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4182 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4183 $ 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
4184 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4185 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
4186 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
4187 (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
4188
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4189
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4190 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4191 Before running any code,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4192 <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
4193 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
4194 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
4195 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
4196 and so on.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4197 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
4198 (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
4199 go to negative indices.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4200 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
4201
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4202 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4203 $ 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
4204 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4205 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
4206
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4207 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4208 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
4209 [0] = "b.lua",
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4210 [1] = "t1", [2] = "t2" }
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4211 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4212 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
4213 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
4214 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
4215 For instance, the call
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4216
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4217 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4218 $ 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
4219 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4220 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
4221 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
4222 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
4223 <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
4224 (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
4225 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
4226
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4227
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4228 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4229 In interactive mode,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4230 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
4231 After reading a line,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4232 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
4233 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
4234 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
4235 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
4236 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
4237 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
4238
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4239
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4240 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4241 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
4242 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
4243 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
4244 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
4245 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
4246 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
4247 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
4248
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4249
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4250 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4251 When finishing normally,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4252 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
4253 (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
4254 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
4255 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
4256
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 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4259 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
4260 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
4261 the standalone interpreter skips
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4262 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
4263 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
4264 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
4265 as in
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 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4268 #!/usr/local/bin/lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4269 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4270 (Of course,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4271 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
4272 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
4273 then
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4274
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4275 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4276 #!/usr/bin/env lua
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4277 </pre><p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4278 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
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 <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
4283
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4284 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4285 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
4286 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
4287 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
4288 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
4289 However,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4290 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
4291
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4292
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4293 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4294 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
4295 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
4296 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
4297 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
4298 Therefore,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4299 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
4300 different Lua versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4301 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
4302 using a new version.
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4305 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4306 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
4307 of precompiled chunks;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4308 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
4309
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4310
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4311 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4312 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
4313 change between versions.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4314
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4315
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4316
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4317 <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
4318 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4319
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 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
4322 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
4323 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
4324 some computations
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4325 (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
4326 can give different results.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4327
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4328
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4329 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4330 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
4331 (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
4332 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
4333 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
4334 (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
4335 for an occasional incompatibility;
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4336 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
4337 For good programming,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4338 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
4339 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
4340 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4341
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4342 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4343 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
4344 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
4345 (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
4346 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
4347 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
4348 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
4349
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4350
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4351 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4352 (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
4353 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
4354 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
4355 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4356
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4357 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4358 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
4359 (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
4360 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4361
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4362 </ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4363
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4364
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4365
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4366
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4367 <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
4368 <ul>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4369
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4370 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4371 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
4372 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
4373 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
4374 (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
4375 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
4376 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4377
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4378 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4379 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
4380 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
4381 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4382
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4383 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4384 The <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
4385 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
4386 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4387
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4388 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4389 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
4390 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
4391 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4394 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
4395 <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
4396 <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
4397 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
4398 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
4399 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
4400 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
4401 For the other operations,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4402 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
4403 implement them in Lua.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4404 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4405
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4406 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4407 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
4408 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
4409 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
4410 (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
4411 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
4412 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
4413 (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
4414 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
4415 </li>
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 </ul>
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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4422 <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
4423
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 <ul>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4428 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
4429 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
4430 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
4431 Adapt your code accordingly.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4432 </li>
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 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4435 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
4436 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
4437 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4438
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4439 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4440 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
4441 (<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
4442 <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
4443 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4444 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
4445 </li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4446
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4447 <li>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4448 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
4449 (<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
4450 were deprecated.
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4451 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
4452 (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
4453 </li>
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 </ul>
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
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4460 <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
4461
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4462 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4463 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
4464 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
4465 {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
4466 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
4467 (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
4468 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
4469 Name, Numeral,
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4470 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
4471
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4472
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
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4475 <pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4476
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4477 chunk ::= block
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4478
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4479 block ::= {stat} [retstat]
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4480
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4481 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
4482 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
4483 functioncall |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4484 label |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4485 <b>break</b> |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4486 <b>goto</b> Name |
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4487 <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
4488 <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
4489 <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
4490 <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
4491 <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
4492 <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
4493 <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
4494 <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
4495 <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
4496
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4497 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
4498
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4499 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
4500
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4501 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
4502
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
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4503 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
4504
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
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4505 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
4506
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4507 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
4508
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4509 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
4510
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4511 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
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parents:
diff changeset
4512 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
4513
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4514 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
4515
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4516 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
4517
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
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4518 args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo; | tableconstructor | LiteralString
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
4519
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4520 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
4521
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4522 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
4523
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4524 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
4525
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4526 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
4527
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4528 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
4529
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4530 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
4531
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4532 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
4533
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4534 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
4535 &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
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parents:
diff changeset
4536 &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
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parents:
diff changeset
4537 <b>and</b> | <b>or</b>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
4538
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4539 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
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parents:
diff changeset
4540
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4541 </pre>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
4542
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4543 <p>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4544
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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parents:
diff changeset
4545
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4546
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
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diff changeset
4547
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4548
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4549
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4550
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4551
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4552 <HR>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4553 <SMALL CLASS="footer">
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4554 Last update:
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
Franklin Schmidt <fschmidt@gmail.com>
parents:
diff changeset
4555 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
4556 </SMALL>
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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diff changeset
4557 <!--
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4558 Last change: minor edit
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4559 -->
e01cddba3433 add manual.html as copy of Lua 5.3 Reference Manual
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4560
372
f08cefa4594c start editing manual
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diff changeset
4561 </div>
386
db23f654f87d make all of website use luan
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diff changeset
4562
391
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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diff changeset
4563 </body>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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diff changeset
4564 </html>
2f5cc9c2cbf0 replace Html.simply_html_page with simply_html_head and simply_html_body_bottom
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diff changeset
4565 <%
386
db23f654f87d make all of website use luan
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diff changeset
4566 end