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<div class="titlepage"><div><div><h3 class="title">
<a name="fusion.support.is_sequence"></a><a class="link" href="is_sequence.html" title="is_sequence">is_sequence</a>
</h3></div></div></div>
<a name="fusion.support.is_sequence.description"></a><h5>
<a name="fusion.support.is_sequence.description-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.description">Description</a>
      </h5>
<p>
        Metafunction that evaluates to <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
        if a certain type <code class="computeroutput"><span class="identifier">T</span></code> is a
        conforming Fusion <a class="link" href="../sequence.html" title="Sequence">Sequence</a>, <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span></code>
        otherwise. This may be specialized to accomodate clients which provide Fusion
        conforming sequences.
      </p>
<a name="fusion.support.is_sequence.synopsis"></a><h5>
<a name="fusion.support.is_sequence.synopsis-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.synopsis">Synopsis</a>
      </h5>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">traits</span>
<span class="special">{</span>
    <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
    <span class="keyword">struct</span> <span class="identifier">is_sequence</span>
    <span class="special">{</span>
        <span class="keyword">typedef</span> <span class="emphasis"><em>unspecified</em></span> <span class="identifier">type</span><span class="special">;</span>
    <span class="special">};</span>
<span class="special">}</span>
</pre>
<a name="fusion.support.is_sequence.parameters"></a><h5>
<a name="fusion.support.is_sequence.parameters-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.parameters">Parameters</a>
      </h5>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
<col>
</colgroup>
<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">T</span></code>
                </p>
              </td>
<td>
                <p>
                  Any type
                </p>
              </td>
<td>
                <p>
                  The type to query.
                </p>
              </td>
</tr></tbody>
</table></div>
<a name="fusion.support.is_sequence.expression_semantics"></a><h5>
<a name="fusion.support.is_sequence.expression_semantics-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.expression_semantics">Expression
        Semantics</a>
      </h5>
<pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">c</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Return type</strong></span>: An <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL
        Boolean Constant</a>.
      </p>
<p>
        <span class="bold"><strong>Semantics</strong></span>: Metafunction that evaluates to
        <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code> if a certain type <code class="computeroutput"><span class="identifier">T</span></code>
        is a conforming Fusion sequence, <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span></code>
        otherwise.
      </p>
<a name="fusion.support.is_sequence.header"></a><h5>
<a name="fusion.support.is_sequence.header-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.header">Header</a>
      </h5>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">support</span><span class="special">/</span><span class="identifier">is_sequence</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</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">is_sequence</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<a name="fusion.support.is_sequence.example"></a><h5>
<a name="fusion.support.is_sequence.example-heading"></a>
        <a class="link" href="is_sequence.html#fusion.support.is_sequence.example">Example</a>
      </h5>
<pre class="programlisting"><span class="identifier">BOOST_MPL_ASSERT_NOT</span><span class="special">((</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="special">));</span>
<span class="identifier">BOOST_MPL_ASSERT_NOT</span><span class="special">((</span> <span class="identifier">is_sequence</span><span class="special">&lt;</span> <span class="keyword">int</span> <span class="special">&gt;</span> <span class="special">));</span>
<span class="identifier">BOOST_MPL_ASSERT</span><span class="special">((</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span><a class="link" href="../container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><span class="special">&lt;&gt;</span> <span class="special">&gt;</span> <span class="special">));</span>
<span class="identifier">BOOST_MPL_ASSERT</span><span class="special">((</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span><a class="link" href="../container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="special">));</span>
<span class="identifier">BOOST_MPL_ASSERT</span><span class="special">((</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span><a class="link" href="../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a><span class="special">&lt;&gt;</span> <span class="special">&gt;</span> <span class="special">));</span>
<span class="identifier">BOOST_MPL_ASSERT</span><span class="special">((</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_sequence</span><span class="special">&lt;</span><a class="link" href="../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="special">));</span>
</pre>
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