ceph/src/boost/libs/phoenix/doc/html/phoenix/modules/scope/local_variables.html

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  27 <a name="phoenix.modules.scope.local_variables"></a><a class="link" href="local_variables.html" title="Local Variables">Local Variables</a>
  28 </h4></div></div></div>
  29 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">phoenix</span><span class="special">/</span><span class="identifier">scope</span><span class="special">/</span><span class="identifier">local_variable</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  30 </pre>
  31 <p>
  32           We use an instance of:
  33         </p>
  34 <pre class="programlisting"><span class="identifier">expression</span><span class="special">::</span><span class="identifier">local_variable</span><span class="special">&lt;</span><span class="identifier">Key</span><span class="special">&gt;::</span><span class="identifier">type</span>
  35 </pre>
  36 <p>
  37           to represent a local variable. The local variable acts as an imaginary
  38           data-bin where a local, stack based data will be placed. <code class="computeroutput"><span class="identifier">Key</span></code> is an arbitrary type that is used
  39           to identify the local variable. Example:
  40         </p>
  41 <pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">size_key</span><span class="special">;</span>
  42 <span class="identifier">expression</span><span class="special">::</span><span class="identifier">local_variable</span><span class="special">&lt;</span><span class="identifier">size_key</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">size</span><span class="special">;</span>
  43 </pre>
  44 <p>
  45           <span class="bold"><strong>Predefined Local Variables</strong></span>
  46         </p>
  47 <p>
  48           There are a few predefined instances of <code class="computeroutput"><span class="identifier">expression</span><span class="special">::</span><span class="identifier">local_variable</span><span class="special">&lt;</span><span class="identifier">Key</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
  49           named <code class="computeroutput"><span class="identifier">_a</span></code>..<code class="computeroutput"><span class="identifier">_z</span></code> that you can already use. To make
  50           use of them, simply use the <code class="computeroutput"><span class="keyword">namespace</span>
  51           <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">::</span><span class="identifier">local_names</span></code>:
  52         </p>
  53 <pre class="programlisting"><span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">::</span><span class="identifier">local_names</span><span class="special">;</span>
  54 </pre>
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  58 <td align="right"><div class="copyright-footer">Copyright &#169; 2002-2005, 2010, 2014, 2015 Joel de Guzman, Dan Marsden, Thomas
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  60         Distributed under the Boost Software License, Version 1.0. (See accompanying
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