ceph/src/boost/libs/scope_exit/doc/html/BOOST_SCOPE_EXIT_CONFIG_USE_LAMBDAS.html

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  28 <h2><span class="refentrytitle">Macro BOOST_SCOPE_EXIT_CONFIG_USE_LAMBDAS</span></h2>
  29 <p>BOOST_SCOPE_EXIT_CONFIG_USE_LAMBDAS &#8212; Force to use C++11 lambda functions to implement scope exits. </p>
  30 </div>
  31 <h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
  32 <div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="reference.html#header.boost.scope_exit_hpp" title="Header &lt;boost/scope_exit.hpp&gt;">boost/scope_exit.hpp</a>&gt;
  33
  34 </span>BOOST_SCOPE_EXIT_CONFIG_USE_LAMBDAS</pre></div>
  35 <div class="refsect1">
  36 <a name="id879590"></a><h2>Description</h2>
  37 <p>If programmers define this configuration macro on a C++11 compiler for which the Boost.Config macro <code class="computeroutput">BOOST_NO_CXX11_LAMBDAS</code> is not defined, the  <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT.html" title="Macro BOOST_SCOPE_EXIT">BOOST_SCOPE_EXIT</a></code> and <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_TPL.html" title="Macro BOOST_SCOPE_EXIT_TPL">BOOST_SCOPE_EXIT_TPL</a></code> macros will use C++11 lambda functions to declare scope exits. By default this macro is not defined.</p>
  38 <p><span class="bold"><strong>Warning:</strong></span> When scope exits are implemented using lambda functions, the syntax of the capture list follows the exact same syntax of C++11 lambda captures which is in general different from the legacy capture syntax of this library. For example, C++11 lambdas require to capture data members by capturing the object <code class="computeroutput">this</code> while this library always allowed to capture data members directly. Therefore, when this configuration macro is defined,  <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT.html" title="Macro BOOST_SCOPE_EXIT">BOOST_SCOPE_EXIT</a></code> and <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_TPL.html" title="Macro BOOST_SCOPE_EXIT_TPL">BOOST_SCOPE_EXIT_TPL</a></code> are no longer backward compatible (and this is why this macro is not defined by default).</p>
  39 <p>A semicolon <code class="computeroutput">;</code> can be used instead of <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_END.html" title="Macro BOOST_SCOPE_EXIT_END">BOOST_SCOPE_EXIT_END</a></code> when this configuration macro is defined (but it is recommended to always use  <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_END.html" title="Macro BOOST_SCOPE_EXIT_END">BOOST_SCOPE_EXIT_END</a></code> so to maximize portability).</p>
  40 <p><span class="bold"><strong>Note:</strong></span> This configuration macro does not control the definition of  <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_ALL.html" title="Macro BOOST_SCOPE_EXIT_ALL">BOOST_SCOPE_EXIT_ALL</a></code> which is always and automatically defined on compilers that support C++11 lambda functions.</p>
  41 <p><span class="bold"><strong>See:</strong></span> <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT.html" title="Macro BOOST_SCOPE_EXIT">BOOST_SCOPE_EXIT</a></code>, <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_TPL.html" title="Macro BOOST_SCOPE_EXIT_TPL">BOOST_SCOPE_EXIT_TPL</a></code>,  <code class="computeroutput"><a class="link" href="BOOST_SCOPE_EXIT_END.html" title="Macro BOOST_SCOPE_EXIT_END">BOOST_SCOPE_EXIT_END</a></code>. </p>
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  46 <td align="right"><div class="copyright-footer">Copyright &#169; 2006-2012 Alexander Nasonov, Lorenzo Caminiti<p>
  47         Distributed under the Boost Software License, Version 1.0 (see accompanying
  48         file LICENSE_1_0.txt or a 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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