1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>find</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="Chapter 1. Fusion 2.2"> 8<link rel="up" href="../functions.html" title="Functions"> 9<link rel="prev" href="none.html" title="none"> 10<link rel="next" href="find_if.html" title="find_if"> 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="none.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../functions.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="find_if.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="fusion.algorithm.query.functions.find"></a><a class="link" href="find.html" title="find">find</a> 28</h5></div></div></div> 29<h6> 30<a name="fusion.algorithm.query.functions.find.h0"></a> 31 <span class="phrase"><a name="fusion.algorithm.query.functions.find.description"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.description">Description</a> 32 </h6> 33<p> 34 Finds the first element of a given type within a sequence. 35 </p> 36<h6> 37<a name="fusion.algorithm.query.functions.find.h1"></a> 38 <span class="phrase"><a name="fusion.algorithm.query.functions.find.synopsis"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.synopsis">Synopsis</a> 39 </h6> 40<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> 41 <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> 42 <span class="keyword">typename</span> <span class="identifier">Sequence</span> 43 <span class="special">></span> 44<span class="keyword">typename</span> <a class="link" href="../metafunctions/find.html" title="find"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">find</span></code></a><span class="special"><</span><span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">,</span> <span class="identifier">T</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">find</span><span class="special">(</span><span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">);</span> 45 46<span class="keyword">template</span><span class="special"><</span> 47 <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> 48 <span class="keyword">typename</span> <span class="identifier">Sequence</span> 49 <span class="special">></span> 50<span class="keyword">typename</span> <a class="link" href="../metafunctions/find.html" title="find"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">find</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">,</span> <span class="identifier">T</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">find</span><span class="special">(</span><span class="identifier">Sequence</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">);</span> 51</pre> 52<div class="table"> 53<a name="fusion.algorithm.query.functions.find.t0"></a><p class="title"><b>Table 1.55. Parameters</b></p> 54<div class="table-contents"><table class="table" summary="Parameters"> 55<colgroup> 56<col> 57<col> 58<col> 59</colgroup> 60<thead><tr> 61<th> 62 <p> 63 Parameter 64 </p> 65 </th> 66<th> 67 <p> 68 Requirement 69 </p> 70 </th> 71<th> 72 <p> 73 Description 74 </p> 75 </th> 76</tr></thead> 77<tbody> 78<tr> 79<td> 80 <p> 81 <code class="computeroutput"><span class="identifier">seq</span></code> 82 </p> 83 </td> 84<td> 85 <p> 86 A model of <a class="link" href="../../../sequence/concepts/forward_sequence.html" title="Forward Sequence">Forward 87 Sequence</a> 88 </p> 89 </td> 90<td> 91 <p> 92 The sequence to search 93 </p> 94 </td> 95</tr> 96<tr> 97<td> 98 <p> 99 <code class="computeroutput"><span class="identifier">T</span></code> 100 </p> 101 </td> 102<td> 103 <p> 104 Any type 105 </p> 106 </td> 107<td> 108 <p> 109 The type to search for 110 </p> 111 </td> 112</tr> 113</tbody> 114</table></div> 115</div> 116<br class="table-break"><h6> 117<a name="fusion.algorithm.query.functions.find.h2"></a> 118 <span class="phrase"><a name="fusion.algorithm.query.functions.find.expression_semantics"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.expression_semantics">Expression 119 Semantics</a> 120 </h6> 121<pre class="programlisting"><a class="link" href="find.html" title="find"><code class="computeroutput"><span class="identifier">find</span></code></a><span class="special"><</span><span class="identifier">T</span><span class="special">>(</span><span class="identifier">seq</span><span class="special">)</span> 122</pre> 123<p> 124 <span class="bold"><strong>Return type</strong></span>: A model of the same iterator 125 category as the iterators of <code class="computeroutput"><span class="identifier">seq</span></code>. 126 </p> 127<p> 128 <span class="bold"><strong>Semantics</strong></span>: Returns an iterator to the 129 first element of <code class="computeroutput"><span class="identifier">seq</span></code> 130 of type <code class="computeroutput"><span class="identifier">T</span></code>, or <code class="computeroutput"><a class="link" href="../../../sequence/intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">seq</span><span class="special">)</span></code> if there is no such element. Equivalent 131 to <code class="computeroutput"><a class="link" href="find_if.html" title="find_if"><code class="computeroutput"><span class="identifier">find_if</span></code></a><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">is_same</span><span class="special"><</span><span class="identifier">_</span><span class="special">,</span> <span class="identifier">T</span><span class="special">></span> <span class="special">>(</span><span class="identifier">seq</span><span class="special">)</span></code> 132 </p> 133<h6> 134<a name="fusion.algorithm.query.functions.find.h3"></a> 135 <span class="phrase"><a name="fusion.algorithm.query.functions.find.complexity"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.complexity">Complexity</a> 136 </h6> 137<p> 138 Linear. At most <code class="computeroutput"><a class="link" href="../../../sequence/intrinsic/metafunctions/size.html" title="size"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">size</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">>::</span><span class="identifier">value</span></code> comparisons. 139 </p> 140<h6> 141<a name="fusion.algorithm.query.functions.find.h4"></a> 142 <span class="phrase"><a name="fusion.algorithm.query.functions.find.header"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.header">Header</a> 143 </h6> 144<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">/</span><span class="identifier">query</span><span class="special">/</span><span class="identifier">find</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 145<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">find</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 146</pre> 147<h6> 148<a name="fusion.algorithm.query.functions.find.h5"></a> 149 <span class="phrase"><a name="fusion.algorithm.query.functions.find.example"></a></span><a class="link" href="find.html#fusion.algorithm.query.functions.find.example">Example</a> 150 </h6> 151<pre class="programlisting"><span class="keyword">const</span> <a class="link" href="../../../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a><span class="special"><</span><span class="keyword">char</span><span class="special">,</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">vec</span><span class="special">(</span><span class="char">'a'</span><span class="special">,</span><span class="char">'0'</span><span class="special">);</span> 152<span class="identifier">assert</span><span class="special">(*</span><a class="link" href="find.html" title="find"><code class="computeroutput"><span class="identifier">find</span></code></a><span class="special"><</span><span class="keyword">int</span><span class="special">>(</span><span class="identifier">vec</span><span class="special">)</span> <span class="special">==</span> <span class="char">'0'</span><span class="special">);</span> 153<span class="identifier">assert</span><span class="special">(</span><a class="link" href="find.html" title="find"><code class="computeroutput"><span class="identifier">find</span></code></a><span class="special"><</span><span class="keyword">double</span><span class="special">>(</span><span class="identifier">vec</span><span class="special">)</span> <span class="special">==</span> <a class="link" href="../../../sequence/intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">vec</span><span class="special">));</span> 154</pre> 155</div> 156<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 157<td align="left"></td> 158<td align="right"><div class="copyright-footer">Copyright © 2001-2006, 2011, 2012 Joel de Guzman, 159 Dan Marsden, Tobias Schwinger<p> 160 Distributed under the Boost Software License, Version 1.0. (See accompanying 161 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>) 162 </p> 163</div></td> 164</tr></table> 165<hr> 166<div class="spirit-nav"> 167<a accesskey="p" href="none.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../functions.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="find_if.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 168</div> 169</body> 170</html> 171
