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| <div class="titlepage"><div><div><h5 class="title"> |
| <a name="fusion.sequence.intrinsic.functions.empty"></a><a class="link" href="empty.html" title="empty">empty</a> |
| </h5></div></div></div> |
| <a name="fusion.sequence.intrinsic.functions.empty.description"></a><h6> |
| <a name="id880296"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.description">Description</a> |
| </h6> |
| <p> |
| Returns a type convertible to <code class="computeroutput"><span class="keyword">bool</span></code> |
| that evaluates to <code class="computeroutput"><span class="keyword">true</span></code> if |
| the sequence is empty, else, evaluates to <code class="computeroutput"><span class="keyword">false</span></code>. |
| </p> |
| <a name="fusion.sequence.intrinsic.functions.empty.synopsis"></a><h6> |
| <a name="id880336"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.synopsis">Synopsis</a> |
| </h6> |
| <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Sequence</span><span class="special">></span> |
| <span class="keyword">typename</span> <a class="link" href="../metafunctions/empty.html" title="empty"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">empty</span></code></a><span class="special"><</span><span class="identifier">Sequence</span><span class="special">>::</span><span class="identifier">type</span> |
| <span class="identifier">empty</span><span class="special">(</span><span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">);</span> |
| </pre> |
| <a name="fusion.sequence.intrinsic.functions.empty.parameters"></a><h6> |
| <a name="id880439"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.parameters">Parameters</a> |
| </h6> |
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| <thead><tr> |
| <th> |
| <p> |
| Parameter |
| </p> |
| </th> |
| <th> |
| <p> |
| Requirement |
| </p> |
| </th> |
| <th> |
| <p> |
| Description |
| </p> |
| </th> |
| </tr></thead> |
| <tbody><tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">seq</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Model of <a class="link" href="../../concepts/forward_sequence.html" title="Forward Sequence">Forward |
| Sequence</a> |
| </p> |
| </td> |
| <td> |
| <p> |
| The sequence we wish to investigate. |
| </p> |
| </td> |
| </tr></tbody> |
| </table></div> |
| <a name="fusion.sequence.intrinsic.functions.empty.expression_semantics"></a><h6> |
| <a name="id880534"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.expression_semantics">Expression |
| Semantics</a> |
| </h6> |
| <pre class="programlisting"><span class="identifier">empty</span><span class="special">(</span><span class="identifier">seq</span><span class="special">);</span> |
| </pre> |
| <p> |
| <span class="bold"><strong>Return type</strong></span>: Convertible to <code class="computeroutput"><span class="keyword">bool</span></code>. |
| </p> |
| <p> |
| <span class="bold"><strong>Semantics</strong></span>: Evaluates to <code class="computeroutput"><span class="keyword">true</span></code> if the sequence is empty, else, evaluates |
| to <code class="computeroutput"><span class="keyword">false</span></code>. |
| </p> |
| <a name="fusion.sequence.intrinsic.functions.empty.header"></a><h6> |
| <a name="id880608"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.header">Header</a> |
| </h6> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">sequence</span><span class="special">/</span><span class="identifier">intrinsic</span><span class="special">/</span><span class="identifier">empty</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">empty</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| </pre> |
| <a name="fusion.sequence.intrinsic.functions.empty.example"></a><h6> |
| <a name="id880723"></a> |
| <a class="link" href="empty.html#fusion.sequence.intrinsic.functions.empty.example">Example</a> |
| </h6> |
| <pre class="programlisting"><a class="link" href="../../../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">int</span><span class="special">,</span> <span class="keyword">int</span><span class="special">></span> <span class="identifier">v</span><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="number">2</span><span class="special">,</span> <span class="number">3</span><span class="special">);</span> |
| <span class="identifier">assert</span><span class="special">(</span><span class="identifier">empty</span><span class="special">(</span><span class="identifier">v</span><span class="special">)</span> <span class="special">==</span> <span class="keyword">false</span><span class="special">);</span> |
| </pre> |
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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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