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| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_typetraits.reference.conditional"></a><a class="link" href="conditional.html" title="conditional">conditional</a> |
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| <p> |
| <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span> |
| <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">conditional</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> |
| or <code class="computeroutput"> <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> |
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| <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> |
| <span class="keyword">template</span> <span class="special"><</span><span class="keyword">bool</span> <span class="identifier">B</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U</span><span class="special">></span> <span class="keyword">struct</span> <a class="link" href="conditional.html" title="conditional">conditional</a><span class="special">;</span> |
| <span class="special">}</span> |
| </pre> |
| <p> |
| If B is true, the member typedef type shall equal T. If B is false, the member |
| typedef type shall equal U. |
| </p> |
| <p> |
| This trait is really just an alias for <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">if_c</span></code>. |
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| <td align="right"><div class="copyright-footer">Copyright © 2000, 2011 Adobe Systems Inc, David Abrahams, |
| Frederic Bron, Steve Cleary, Beman Dawes, Aleksey Gurtovoy, Howard Hinnant, |
| Jesse Jones, Mat Marcus, Itay Maman, John Maddock, Alexander Nasonov, Thorsten |
| Ottosen, Roman Perepelitsa, Robert Ramey, Jeremy Siek, Robert Stewart and Steven |
| Watanabe<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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