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| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="fusion.tuple.pairs"></a><a class="link" href="pairs.html" title="Pairs">Pairs</a> |
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| <a name="fusion.tuple.pairs.description"></a><h5> |
| <a name="id1061173"></a> |
| <a class="link" href="pairs.html#fusion.tuple.pairs.description">Description</a> |
| </h5> |
| <p> |
| The <a href="http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2002/n1403.pdf" target="_top">TR1 |
| Tuple</a> interface is specified to provide uniform access to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code> |
| as if it were a 2 element tuple. |
| </p> |
| <a name="fusion.tuple.pairs.specification"></a><h5> |
| <a name="id1061211"></a> |
| <a class="link" href="pairs.html#fusion.tuple.pairs.specification">Specification</a> |
| </h5> |
| <pre class="programlisting"><span class="identifier">tuple_size</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">></span> <span class="special">>::</span><span class="identifier">value</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Type</strong></span>: An <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL |
| Integral Constant</a> |
| </p> |
| <p> |
| <span class="bold"><strong>Value</strong></span>: Returns 2, the number of elements |
| in a pair. |
| </p> |
| <pre class="programlisting"><span class="identifier">tuple_element</span><span class="special"><</span><span class="number">0</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Type</strong></span>: <code class="computeroutput"><span class="identifier">T1</span></code> |
| </p> |
| <p> |
| <span class="bold"><strong>Value</strong></span>: Returns the type of the first element |
| of the pair |
| </p> |
| <pre class="programlisting"><span class="identifier">tuple_element</span><span class="special"><</span><span class="number">1</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Type</strong></span>: <code class="computeroutput"><span class="identifier">T2</span></code> |
| </p> |
| <p> |
| <span class="bold"><strong>Value</strong></span>: Returns thetype of the second element |
| of the pair |
| </p> |
| <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">int</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T2</span><span class="special">></span> |
| <span class="identifier">P</span><span class="special">&</span> <span class="identifier">get</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">>&</span> <span class="identifier">pr</span><span class="special">);</span> |
| |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">int</span> <span class="identifier">I</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T2</span><span class="special">></span> |
| <span class="keyword">const</span> <span class="identifier">P</span><span class="special">&</span> <span class="identifier">get</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">>&</span> <span class="identifier">pr</span><span class="special">);</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Type</strong></span>: If <code class="computeroutput"><span class="identifier">I</span> |
| <span class="special">==</span> <span class="number">0</span></code> |
| <code class="computeroutput"><span class="identifier">P</span></code> is <code class="computeroutput"><span class="identifier">T1</span></code>, |
| else if <code class="computeroutput"><span class="identifier">I</span> <span class="special">==</span> |
| <span class="number">1</span></code> <code class="computeroutput"><span class="identifier">P</span></code> |
| is <code class="computeroutput"><span class="identifier">T2</span></code> else the program is |
| ill-formed. |
| </p> |
| <p> |
| <span class="bold"><strong>Returns: <code class="computeroutput"><span class="identifier">pr</span><span class="special">.</span><span class="identifier">first</span></code> |
| if <code class="computeroutput"><span class="identifier">I</span> <span class="special">==</span> |
| <span class="number">0</span></code> else <code class="computeroutput"><span class="identifier">pr</span><span class="special">.</span><span class="identifier">second</span></code>.</strong></span>[*Returns: |
| <code class="computeroutput"><span class="identifier">pr</span><span class="special">.</span><span class="identifier">first</span></code> if <code class="computeroutput"><span class="identifier">I</span> |
| <span class="special">==</span> <span class="number">0</span></code> |
| else <code class="computeroutput"><span class="identifier">pr</span><span class="special">.</span><span class="identifier">second</span></code>. |
| </p> |
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| <td align="right"><div class="copyright-footer">Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias |
| Schwinger<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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