boost_mpl/doc/refmanual/void.html

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<div class="section" id="void">
<h1><a class="toc-backref" href="./data-miscellaneous.html#id508" name="void">void_</a></h1>
<div class="section" id="void-synopsis">
<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3>
<pre class="literal-block">
struct <a href="./void.html" class="identifier">void_</a>
{
    typedef <a href="./void.html" class="identifier">void_</a> type;
};

template&lt; typename T &gt; struct is_void;
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<h3><a class="subsection-title" href="#description" name="description">Description</a></h3>
<p><tt class="literal"><span class="pre"><a href="./void.html" class="identifier">void_</a></span></tt> is a generic type placeholder representing &quot;nothing&quot;.</p>
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<pre class="literal-block">
#include &lt;<a href="../../../../boost/mpl/void.hpp" class="header">boost/mpl/void.hpp</a>&gt;
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<p><a class="reference" href="./data-types.html">Data Types</a>, <a class="refentry reference" href="./pair.html"><tt class="refentry literal"><span class="pre">pair</span></tt></a>, <a class="refentry reference" href="./empty-base.html"><tt class="refentry literal"><span class="pre">empty_base</span></tt></a>, <a class="refentry reference" href="./bool.html"><tt class="refentry literal"><span class="pre">bool_</span></tt></a>, <a class="refentry reference" href="./int.html"><tt class="refentry literal"><span class="pre">int_</span></tt></a>, <a class="refentry reference" href="./integral-c.html"><tt class="refentry literal"><span class="pre">integral_c</span></tt></a></p>
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