1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>for_each</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="accumulate.html" title="accumulate"> 10<link rel="next" href="../metafunctions.html" title="Metafunctions"> 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="accumulate.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="../metafunctions.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.iteration.functions.for_each"></a><a class="link" href="for_each.html" title="for_each">for_each</a> 28</h5></div></div></div> 29<h6> 30<a name="fusion.algorithm.iteration.functions.for_each.h0"></a> 31 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.description"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.description">Description</a> 32 </h6> 33<p> 34 Applies a unary function object to each element of a sequence. 35 </p> 36<h6> 37<a name="fusion.algorithm.iteration.functions.for_each.h1"></a> 38 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.synopsis"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.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">Sequence</span><span class="special">,</span> 42 <span class="keyword">typename</span> <span class="identifier">F</span> 43 <span class="special">></span> 44<span class="keyword">typename</span> <a class="link" href="../metafunctions/for_each.html" title="for_each"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">for_each</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">,</span> <span class="identifier">F</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">for_each</span><span class="special">(</span> 45 <span class="identifier">Sequence</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">,</span> <span class="identifier">F</span> <span class="identifier">f</span><span class="special">);</span> 46</pre> 47<div class="table"> 48<a name="fusion.algorithm.iteration.functions.for_each.t0"></a><p class="title"><b>Table 1.45. Parameters</b></p> 49<div class="table-contents"><table class="table" summary="Parameters"> 50<colgroup> 51<col> 52<col> 53<col> 54</colgroup> 55<thead><tr> 56<th> 57 <p> 58 Parameter 59 </p> 60 </th> 61<th> 62 <p> 63 Requirement 64 </p> 65 </th> 66<th> 67 <p> 68 Description 69 </p> 70 </th> 71</tr></thead> 72<tbody> 73<tr> 74<td> 75 <p> 76 <code class="computeroutput"><span class="identifier">seq</span></code> 77 </p> 78 </td> 79<td> 80 <p> 81 A model of <a class="link" href="../../../sequence/concepts/forward_sequence.html" title="Forward Sequence">Forward 82 Sequence</a>, <code class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">e</span><span class="special">)</span></code> must be a valid expression 83 for each element <code class="computeroutput"><span class="identifier">e</span></code> 84 in <code class="computeroutput"><span class="identifier">seq</span></code> 85 </p> 86 </td> 87<td> 88 <p> 89 Operation's argument 90 </p> 91 </td> 92</tr> 93<tr> 94<td> 95 <p> 96 <code class="computeroutput"><span class="identifier">f</span></code> 97 </p> 98 </td> 99<td> 100 <p> 101 A unary <a class="link" href="../../../functional/concepts/reg_callable.html" title="Regular Callable Object">Regular 102 Callable Object</a> 103 </p> 104 </td> 105<td> 106 <p> 107 Operation's argument 108 </p> 109 </td> 110</tr> 111</tbody> 112</table></div> 113</div> 114<br class="table-break"><h6> 115<a name="fusion.algorithm.iteration.functions.for_each.h2"></a> 116 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.expression_semantics"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.expression_semantics">Expression 117 Semantics</a> 118 </h6> 119<pre class="programlisting"><a class="link" href="for_each.html" title="for_each"><code class="computeroutput"><span class="identifier">for_each</span></code></a><span class="special">(</span><span class="identifier">seq</span><span class="special">,</span> <span class="identifier">f</span><span class="special">);</span> 120</pre> 121<p> 122 <span class="bold"><strong>Return type</strong></span>: <code class="computeroutput"><span class="keyword">void</span></code> 123 </p> 124<p> 125 <span class="bold"><strong>Semantics</strong></span>: Calls <code class="computeroutput"><span class="identifier">f</span><span class="special">(</span><span class="identifier">e</span><span class="special">)</span></code> for each element <code class="computeroutput"><span class="identifier">e</span></code> 126 in <code class="computeroutput"><span class="identifier">seq</span></code>. 127 </p> 128<h6> 129<a name="fusion.algorithm.iteration.functions.for_each.h3"></a> 130 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.complexity"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.complexity">Complexity</a> 131 </h6> 132<p> 133 Linear, exactly <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> applications of <code class="computeroutput"><span class="identifier">f</span></code>. 134 </p> 135<h6> 136<a name="fusion.algorithm.iteration.functions.for_each.h4"></a> 137 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.header"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.header">Header</a> 138 </h6> 139<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">iteration</span><span class="special">/</span><span class="identifier">for_each</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 140<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">for_each</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 141</pre> 142<h6> 143<a name="fusion.algorithm.iteration.functions.for_each.h5"></a> 144 <span class="phrase"><a name="fusion.algorithm.iteration.functions.for_each.example"></a></span><a class="link" href="for_each.html#fusion.algorithm.iteration.functions.for_each.example">Example</a> 145 </h6> 146<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">increment</span> 147<span class="special">{</span> 148 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">></span> 149 <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">T</span><span class="special">&</span> <span class="identifier">t</span><span class="special">)</span> <span class="keyword">const</span> 150 <span class="special">{</span> 151 <span class="special">++</span><span class="identifier">t</span><span class="special">;</span> 152 <span class="special">}</span> 153<span class="special">};</span> 154<span class="special">...</span> 155<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">int</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="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">);</span> 156<a class="link" href="for_each.html" title="for_each"><code class="computeroutput"><span class="identifier">for_each</span></code></a><span class="special">(</span><span class="identifier">vec</span><span class="special">,</span> <span class="identifier">increment</span><span class="special">());</span> 157<span class="identifier">assert</span><span class="special">(</span><span class="identifier">vec</span> <span class="special">==</span> <a class="link" href="../../../container/generation/functions/make_vector.html" title="make_vector"><code class="computeroutput"><span class="identifier">make_vector</span></code></a><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">));</span> 158</pre> 159</div> 160<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 161<td align="left"></td> 162<td align="right"><div class="copyright-footer">Copyright © 2001-2006, 2011, 2012 Joel de Guzman, 163 Dan Marsden, Tobias Schwinger<p> 164 Distributed under the Boost Software License, Version 1.0. (See accompanying 165 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>) 166 </p> 167</div></td> 168</tr></table> 169<hr> 170<div class="spirit-nav"> 171<a accesskey="p" href="accumulate.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="../metafunctions.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 172</div> 173</body> 174</html> 175
