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<h2><span class="refentrytitle">Macro BOOST_MOVE_RET</span></h2>
<p>BOOST_MOVE_RET</p>
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<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="move/reference.html#header.boost.move.core_hpp" title="Header <boost/move/core.hpp>">boost/move/core.hpp</a>>
</span>BOOST_MOVE_RET(RET_TYPE, REF)</pre></div>
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<a name="idp405833872"></a><h2>Description</h2>
<p>This macro is used to achieve portable move return semantics. The C++11 Standard allows implicit move returns when the object to be returned is designated by a lvalue and:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>The criteria for elision of a copy operation are met OR</p></li>
<li class="listitem"><p>The criteria would be met save for the fact that the source object is a function parameter</p></li>
</ul></div>
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<p>For C++11 conforming compilers this macros only yields to REF: <code class="computeroutput">return BOOST_MOVE_RET(RET_TYPE, REF);</code> -> <code class="computeroutput">return REF;</code></p>
<p>For compilers without rvalue references this macro does an explicit move if the move emulation is activated and the return type (RET_TYPE) is not a reference.</p>
<p>For non-conforming compilers with rvalue references like Visual 2010 & 2012, an explicit move is performed if RET_TYPE is not a reference.</p>
<p><span class="bold"><strong>Caution</strong></span>: When using this macro in non-conforming or C++03 compilers, a move will be performed even if the C++11 standard does not allow it (e.g. returning a static variable). The user is responsible for using this macro only to return local objects that met C++11 criteria. </p>
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<td align="right"><div class="copyright-footer">Copyright © 2008-2014 Ion Gaztanaga<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
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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