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  26 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  27 <a name="move.move_algorithms"></a><a class="link" href="move_algorithms.html" title="Move algorithms">Move algorithms</a>
  28 </h2></div></div></div>
  29 <p>
  30       The standard library offers several copy-based algorithms. Some of them, like
  31       <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code> or <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">uninitialized_copy</span></code>
  32       are basic building blocks for containers and other data structures. This library
  33       offers move-based functions for those purposes:
  34     </p>
  35 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">O</span><span class="special">&gt;</span> <span class="identifier">O</span> <span class="identifier">move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">O</span><span class="special">);</span>
  36 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">O</span><span class="special">&gt;</span> <span class="identifier">O</span> <span class="identifier">move_backward</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">O</span><span class="special">);</span>
  37 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">&gt;</span> <span class="identifier">F</span> <span class="identifier">uninitialized_move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">F</span><span class="special">);</span>
  38 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F</span><span class="special">&gt;</span> <span class="identifier">F</span> <span class="identifier">uninitialized_copy_or_move</span><span class="special">(</span><span class="identifier">I</span><span class="special">,</span> <span class="identifier">I</span><span class="special">,</span> <span class="identifier">F</span><span class="special">);</span>
  39 </pre>
  40 <p>
  41       The first 3 are move variations of their equivalent copy algorithms, but copy
  42       assignment and copy construction are replaced with move assignment and construction.
  43       The last one has the same behaviour as <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">uninitialized_copy</span></code>
  44       but since several standand library implementations don't play very well with
  45       <code class="computeroutput"><span class="identifier">move_iterator</span></code>s, this version
  46       is a portable version for those willing to use move iterators.
  47     </p>
  48 <p>
  49 </p>
  50 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="string">"movable.hpp"</span>
  51 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">cassert</span><span class="special">&gt;</span>
  52 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">aligned_storage</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  53
  54 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
  55 <span class="special">{</span>
  56    <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">ArraySize</span> <span class="special">=</span> <span class="number">10</span><span class="special">;</span>
  57    <span class="identifier">movable</span> <span class="identifier">movable_array</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">];</span>
  58    <span class="identifier">movable</span> <span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">];</span>
  59    <span class="comment">//move</span>
  60    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">move</span><span class="special">(&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">]);</span>
  61    <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  62    <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  63
  64    <span class="comment">//move backward</span>
  65    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">move_backward</span><span class="special">(&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">]);</span>
  66    <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  67    <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  68
  69    <span class="comment">//uninitialized_move</span>
  70    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">aligned_storage</span><span class="special">&lt;</span> <span class="keyword">sizeof</span><span class="special">(</span><span class="identifier">movable</span><span class="special">)*</span><span class="identifier">ArraySize</span>
  71                          <span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">alignment_of</span><span class="special">&lt;</span><span class="identifier">movable</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">storage</span><span class="special">;</span>
  72    <span class="identifier">movable</span> <span class="special">*</span><span class="identifier">raw_movable</span> <span class="special">=</span> <span class="keyword">static_cast</span><span class="special">&lt;</span><span class="identifier">movable</span><span class="special">*&gt;(</span><span class="keyword">static_cast</span><span class="special">&lt;</span><span class="keyword">void</span><span class="special">*&gt;(&amp;</span><span class="identifier">storage</span><span class="special">));</span>
  73    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">uninitialized_move</span><span class="special">(&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">],</span> <span class="special">&amp;</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="identifier">ArraySize</span><span class="special">],</span> <span class="identifier">raw_movable</span><span class="special">);</span>
  74    <span class="identifier">assert</span><span class="special">(</span><span class="identifier">movable_array2</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  75    <span class="identifier">assert</span><span class="special">(!</span><span class="identifier">raw_movable</span><span class="special">[</span><span class="number">0</span><span class="special">].</span><span class="identifier">moved</span><span class="special">());</span>
  76    <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
  77 <span class="special">}</span>
  78 </pre>
  79 <p>
  80     </p>
  81 </div>
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  84 <td align="right"><div class="copyright-footer">Copyright &#169; 2008-2010 Ion Gaztanaga<p>
  85         Distributed under the Boost Software License, Version 1.0. (See accompanying
  86         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>)
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