1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>replaced_if</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. Range 2.0"> 8<link rel="up" href="../reference.html" title="Reference"> 9<link rel="prev" href="replaced.html" title="replaced"> 10<link rel="next" href="reversed.html" title="reversed"> 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="replaced.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.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="reversed.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="range.reference.adaptors.reference.replaced_if"></a><a class="link" href="replaced_if.html" title="replaced_if">replaced_if</a> 28</h5></div></div></div> 29<div class="toc"><dl class="toc"><dt><span class="section"><a href="replaced_if.html#range.reference.adaptors.reference.replaced_if.replaced_if_example">replaced_if 30 example</a></span></dt></dl></div> 31<div class="informaltable"><table class="table"> 32<colgroup> 33<col> 34<col> 35</colgroup> 36<thead><tr> 37<th> 38 <p> 39 Syntax 40 </p> 41 </th> 42<th> 43 <p> 44 Code 45 </p> 46 </th> 47</tr></thead> 48<tbody> 49<tr> 50<td> 51 <p> 52 Pipe 53 </p> 54 </td> 55<td> 56 <p> 57 <code class="computeroutput"><span class="identifier">rng</span> <span class="special">|</span> 58 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">replaced_if</span><span class="special">(</span><span class="identifier">pred</span><span class="special">,</span> 59 <span class="identifier">new_value</span><span class="special">)</span></code> 60 </p> 61 </td> 62</tr> 63<tr> 64<td> 65 <p> 66 Function 67 </p> 68 </td> 69<td> 70 <p> 71 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">replace_if</span><span class="special">(</span><span class="identifier">rng</span><span class="special">,</span> 72 <span class="identifier">pred</span><span class="special">,</span> 73 <span class="identifier">new_value</span><span class="special">)</span></code> 74 </p> 75 </td> 76</tr> 77</tbody> 78</table></div> 79<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 80<li class="listitem"> 81 <span class="bold"><strong>Precondition:</strong></span> 82 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "> 83<li class="listitem"> 84 The range <code class="computeroutput"><span class="identifier">value_type</span></code> 85 is convertible to the argument type of <code class="computeroutput"><span class="identifier">pred</span></code>. 86 </li> 87<li class="listitem"> 88 <code class="computeroutput"><span class="identifier">new_value</span></code> is 89 convertible to the <code class="computeroutput"><span class="identifier">value_type</span></code> 90 of the range. 91 </li> 92</ul></div> 93 </li> 94<li class="listitem"> 95 <span class="bold"><strong>Postconditions:</strong></span> For all elements 96 <code class="computeroutput"><span class="identifier">x</span></code> in the returned 97 range, the value <code class="computeroutput"><span class="identifier">x</span></code> 98 is equal to the value of <code class="computeroutput"><span class="identifier">pred</span><span class="special">(</span><span class="identifier">y</span><span class="special">)</span> <span class="special">?</span> <span class="identifier">new_value</span> <span class="special">:</span> 99 <span class="identifier">y</span></code> where <code class="computeroutput"><span class="identifier">y</span></code> 100 is the corresponding element in the original range. 101 </li> 102<li class="listitem"> 103 <span class="bold"><strong>Range Category:</strong></span> <a class="link" href="../../../concepts/single_pass_range.html" title="Single Pass Range">Single 104 Pass Range</a> 105 </li> 106<li class="listitem"> 107 <span class="bold"><strong>Range Return Type:</strong></span> <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">replaced_if_range</span><span class="special"><</span><span class="keyword">decltype</span><span class="special">(</span><span class="identifier">rng</span><span class="special">)></span></code> 108 </li> 109<li class="listitem"> 110 <span class="bold"><strong>Returned Range Category:</strong></span> The range 111 category of <code class="computeroutput"><span class="identifier">rng</span></code>. 112 </li> 113</ul></div> 114<div class="section"> 115<div class="titlepage"><div><div><h6 class="title"> 116<a name="range.reference.adaptors.reference.replaced_if.replaced_if_example"></a><a class="link" href="replaced_if.html#range.reference.adaptors.reference.replaced_if.replaced_if_example" title="replaced_if example">replaced_if 117 example</a> 118</h6></div></div></div> 119<p> 120</p> 121<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">adaptor</span><span class="special">/</span><span class="identifier">replaced_if</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 122<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">/</span><span class="identifier">copy</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 123<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">assign</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 124<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iterator</span><span class="special">></span> 125<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> 126<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">vector</span><span class="special">></span> 127 128<span class="keyword">struct</span> <span class="identifier">is_even</span> 129<span class="special">{</span> 130 <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">()(</span><span class="keyword">int</span> <span class="identifier">x</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">x</span> <span class="special">%</span> <span class="number">2</span> <span class="special">==</span> <span class="number">0</span><span class="special">;</span> <span class="special">}</span> 131<span class="special">};</span> 132 133<span class="keyword">int</span> <span class="identifier">main</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">argc</span><span class="special">,</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">argv</span><span class="special">[])</span> 134<span class="special">{</span> 135 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">;</span> 136 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">assign</span><span class="special">;</span> 137 138 <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">input</span><span class="special">;</span> 139 <span class="identifier">input</span> <span class="special">+=</span> <span class="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">,</span><span class="number">4</span><span class="special">,</span><span class="number">5</span><span class="special">,</span><span class="number">6</span><span class="special">,</span><span class="number">7</span><span class="special">,</span><span class="number">8</span><span class="special">,</span><span class="number">9</span><span class="special">;</span> 140 141 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span> 142 <span class="identifier">input</span> <span class="special">|</span> <span class="identifier">replaced_if</span><span class="special">(</span><span class="identifier">is_even</span><span class="special">(),</span> <span class="number">10</span><span class="special">),</span> 143 <span class="identifier">std</span><span class="special">::</span><span class="identifier">ostream_iterator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span><span class="special">,</span> <span class="string">","</span><span class="special">));</span> 144 145 <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> 146<span class="special">}</span> 147</pre> 148<p> 149 </p> 150</div> 151<p> 152 This would produce the output: 153</p> 154<pre class="programlisting"><span class="number">1</span><span class="special">,</span><span class="number">10</span><span class="special">,</span><span class="number">3</span><span class="special">,</span><span class="number">10</span><span class="special">,</span><span class="number">5</span><span class="special">,</span><span class="number">10</span><span class="special">,</span><span class="number">7</span><span class="special">,</span><span class="number">10</span><span class="special">,</span><span class="number">9</span><span class="special">,</span> 155</pre> 156<p> 157 </p> 158</div> 159<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 160<td align="left"></td> 161<td align="right"><div class="copyright-footer">Copyright © 2003-2010 Thorsten Ottosen, 162 Neil Groves<p> 163 Distributed under the Boost Software License, Version 1.0. (See accompanying 164 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>) 165 </p> 166</div></td> 167</tr></table> 168<hr> 169<div class="spirit-nav"> 170<a accesskey="p" href="replaced.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.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="reversed.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 171</div> 172</body> 173</html> 174
