1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Kleene Parser (*a)</title> 5<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../../index.html" title="Spirit 2.5.8"> 8<link rel="up" href="../operator.html" title="Parser Operators"> 9<link rel="prev" href="expect.html" title="Expectation Operator (a > b)"> 10<link rel="next" href="list.html" title="List Parser (a % b)"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="expect.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../operator.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="list.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="spirit.qi.reference.operator.kleene"></a><a class="link" href="kleene.html" title="Kleene Parser (*a)">Kleene Parser 28 (<code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>)</a> 29</h5></div></div></div> 30<h6> 31<a name="spirit.qi.reference.operator.kleene.h0"></a> 32 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.description"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.description">Description</a> 33 </h6> 34<p> 35 The kleene operator, <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>, 36 is a unary operator that matches its operand zero or more times. 37 </p> 38<h6> 39<a name="spirit.qi.reference.operator.kleene.h1"></a> 40 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.header"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.header">Header</a> 41 </h6> 42<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/qi/operator/kleene.hpp></span> 43<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_kleene</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 44</pre> 45<p> 46 Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>. 47 </p> 48<h6> 49<a name="spirit.qi.reference.operator.kleene.h2"></a> 50 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.model_of"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.model_of">Model 51 of</a> 52 </h6> 53<div class="blockquote"><blockquote class="blockquote"><p> 54 <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a> 55 </p></blockquote></div> 56<div class="variablelist"> 57<p class="title"><b>Notation</b></p> 58<dl class="variablelist"> 59<dt><span class="term"><code class="computeroutput"><span class="identifier">a</span></code></span></dt> 60<dd><p> 61 A <a class="link" href="../parser_concepts/parser.html" title="Parser"><code class="computeroutput"><span class="identifier">Parser</span></code></a> 62 </p></dd> 63</dl> 64</div> 65<h6> 66<a name="spirit.qi.reference.operator.kleene.h3"></a> 67 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.expression_semantics"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.expression_semantics">Expression 68 Semantics</a> 69 </h6> 70<p> 71 Semantics of an expression is defined only where it differs from, or 72 is not defined in <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a>. 73 </p> 74<div class="informaltable"><table class="table"> 75<colgroup> 76<col> 77<col> 78</colgroup> 79<thead><tr> 80<th> 81 <p> 82 Expression 83 </p> 84 </th> 85<th> 86 <p> 87 Semantics 88 </p> 89 </th> 90</tr></thead> 91<tbody><tr> 92<td> 93 <p> 94 <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code> 95 </p> 96 </td> 97<td> 98 <p> 99 Match <code class="computeroutput"><span class="identifier">a</span></code> zero 100 or more times. 101 </p> 102 </td> 103</tr></tbody> 104</table></div> 105<h6> 106<a name="spirit.qi.reference.operator.kleene.h4"></a> 107 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.attributes"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.attributes">Attributes</a> 108 </h6> 109<p> 110 See <a class="link" href="../../quick_reference/compound_attribute_rules.html#spirit.qi.quick_reference.compound_attribute_rules.notation">Compound 111 Attribute Notation</a>. 112 </p> 113<div class="informaltable"><table class="table"> 114<colgroup> 115<col> 116<col> 117</colgroup> 118<thead><tr> 119<th> 120 <p> 121 Expression 122 </p> 123 </th> 124<th> 125 <p> 126 Attribute 127 </p> 128 </th> 129</tr></thead> 130<tbody><tr> 131<td> 132 <p> 133 <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code> 134 </p> 135 </td> 136<td> 137 <p> 138</p> 139<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--></span> <span class="special">*</span><span class="identifier">a</span><span class="special">:</span> <span class="identifier">vector</span><span class="special"><</span><span class="identifier">A</span><span class="special">></span> 140<span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--></span> <span class="special">*</span><span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span></pre> 141<p> 142 </p> 143 </td> 144</tr></tbody> 145</table></div> 146<h6> 147<a name="spirit.qi.reference.operator.kleene.h5"></a> 148 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.complexity"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.complexity">Complexity</a> 149 </h6> 150<div class="blockquote"><blockquote class="blockquote"><p> 151 The overall complexity of the Kleene star is defined by the complexity 152 of its subject, <code class="computeroutput"><span class="identifier">a</span></code>, 153 multiplied by the number of repetitions. The complexity of the Kleene 154 star itself is O(N), where N is the number successful repetitions. 155 </p></blockquote></div> 156<h6> 157<a name="spirit.qi.reference.operator.kleene.h6"></a> 158 <span class="phrase"><a name="spirit.qi.reference.operator.kleene.example"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.example">Example</a> 159 </h6> 160<div class="note"><table border="0" summary="Note"> 161<tr> 162<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td> 163<th align="left">Note</th> 164</tr> 165<tr><td align="left" valign="top"><p> 166 The test harness for the example(s) below is presented in the <a class="link" href="../basics.html#spirit.qi.reference.basics.examples">Basics Examples</a> 167 section. 168 </p></td></tr> 169</table></div> 170<p> 171 Some using declarations: 172 </p> 173<p> 174</p> 175<pre class="programlisting"><span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">qi</span><span class="special">::</span><span class="identifier">int_</span><span class="special">;</span> 176</pre> 177<p> 178 </p> 179<p> 180 Parse a comma separated list of numbers and put them in a vector: 181 </p> 182<p> 183</p> 184<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">attr</span><span class="special">;</span> 185<span class="identifier">test_phrase_parser_attr</span><span class="special">(</span> 186 <span class="string">"111, 222, 333, 444, 555"</span><span class="special">,</span> <span class="identifier">int_</span> <span class="special">>></span> <span class="special">*(</span><span class="char">','</span> <span class="special">>></span> <span class="identifier">int_</span><span class="special">),</span> <span class="identifier">attr</span><span class="special">);</span> 187<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> 188 <span class="special"><<</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special"><<</span> <span class="char">','</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special"><<</span> <span class="char">','</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">2</span><span class="special">]</span> <span class="special"><<</span> <span class="char">','</span> 189 <span class="special"><<</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">3</span><span class="special">]</span> <span class="special"><<</span> <span class="char">','</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">4</span><span class="special">]</span> 190 <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> 191</pre> 192<p> 193 </p> 194</div> 195<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 196<td align="left"></td> 197<td align="right"><div class="copyright-footer">Copyright © 2001-2011 Joel de Guzman, Hartmut Kaiser<p> 198 Distributed under the Boost Software License, Version 1.0. (See accompanying 199 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 200 </p> 201</div></td> 202</tr></table> 203<hr> 204<div class="spirit-nav"> 205<a accesskey="p" href="expect.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../operator.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="list.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 206</div> 207</body> 208</html> 209
