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| <div class="titlepage"><div><div><h2 class="title" style="clear: both"> |
| <a name="boost_typeerasure.composing_concepts"></a><a class="link" href="composing_concepts.html" title="Composing Concepts">Composing Concepts</a> |
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| (For the source of the examples in this section see <a href="../../../libs/type_erasure/example/compose.cpp" target="_top">compose.cpp</a>) |
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| Multiple concepts can be composed using an MPL sequence. |
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| <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span> <span class="special">=</span> <span class="identifier">_self</span><span class="special">></span> |
| <span class="keyword">struct</span> <span class="identifier">arithmetic</span> <span class="special">:</span> |
| <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span> |
| <span class="identifier">copy_constructible</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">addable</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">subtractable</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">multipliable</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">dividable</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">equality_comparable</span><span class="special"><</span><span class="identifier">T</span><span class="special">>,</span> |
| <span class="identifier">less_than_comparable</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span> |
| <span class="special">></span> |
| <span class="special">{};</span> |
| </pre> |
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| Now, <code class="computeroutput"><span class="identifier">arithmetic</span></code> is a concept |
| that can be used just like any of the base concepts. |
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| <td align="right"><div class="copyright-footer">Copyright © 2011-2013 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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