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| <div class="section" id="void"> |
| <h1><a class="toc-backref" href="./data-types-miscellaneous.html#id1585">void_</a></h1> |
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| <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< typename T > struct is_void; |
| </pre> |
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| <div class="section" id="id1281"> |
| <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 "nothing".</p> |
| <!-- In many cases, returning ``void_`` from a metafunction to signal |
| an absence of the requested data leads to a simpler user code than |
| having a separate metafunction specifically for the purpose of |
| performing the corresponding check. --> |
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| <div class="section" id="id1282"> |
| <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> |
| <pre class="literal-block"> |
| #include <<a href="../../../../boost/mpl/void.hpp" class="header">boost/mpl/void.hpp</a>> |
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| <p><a class="reference internal" href="./data-types.html">Data Types</a>, <a class="reference internal" href="./pair.html">pair</a>, <a class="reference internal" href="./empty-base.html">empty_base</a>, <a class="reference internal" href="./bool.html">bool_</a>, <a class="reference internal" href="./int.html">int_</a>, <a class="reference internal" href="./integral-c.html">integral_c</a></p> |
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| <td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
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