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| 13 | </tr></table><div class="header-separator"></div> |
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| 14 | <div class="section" id="void"> |
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| 15 | <h1><a class="toc-backref" href="./data-miscellaneous.html#id508" name="void">void_</a></h1> |
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| 16 | <div class="section" id="void-synopsis"> |
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| 17 | <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> |
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| 18 | <pre class="literal-block"> |
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| 19 | struct <a href="./void.html" class="identifier">void_</a> |
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| 20 | { |
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| 21 | typedef <a href="./void.html" class="identifier">void_</a> type; |
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| 22 | }; |
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| 23 | |
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| 24 | template< typename T > struct is_void; |
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| 25 | </pre> |
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| 26 | </div> |
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| 27 | <div class="section" id="void-description"> |
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| 28 | <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> |
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| 29 | <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> |
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| 30 | <!-- In many cases, returning ``void_`` from a metafunction to signal |
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| 31 | an absence of the requested data leads to a simpler user code than |
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| 32 | having a separate metafunction specifically for the purpose of |
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| 33 | performing the corresponding check. --> |
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| 34 | </div> |
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| 35 | <div class="section" id="void-header"> |
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| 36 | <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> |
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| 37 | <pre class="literal-block"> |
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| 38 | #include <<a href="../../../../boost/mpl/void.hpp" class="header">boost/mpl/void.hpp</a>> |
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| 39 | </pre> |
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| 40 | </div> |
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| 41 | <div class="section" id="void-see-also"> |
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| 42 | <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> |
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| 43 | <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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| 44 | <!-- modtime: November 10, 2004 04:30:19 +0000 --> |
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