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<div class="titlepage"><div><div><h4 class="title">
<a name="fusion.iterator.metafunctions.value_of_data"></a><a class="link" href="value_of_data.html" title="value_of_data">value_of_data</a>
</h4></div></div></div>
<a name="fusion.iterator.metafunctions.value_of_data.description"></a><h6>
<a name="id867372"></a>
<a class="link" href="value_of_data.html#fusion.iterator.metafunctions.value_of_data.description">Description</a>
</h6>
<p>
Returns the type of the data property associated with the element referenced
by an associative iterator references.
</p>
<a name="fusion.iterator.metafunctions.value_of_data.synopsis"></a><h6>
<a name="id867389"></a>
<a class="link" href="value_of_data.html#fusion.iterator.metafunctions.value_of_data.synopsis">Synopsis</a>
</h6>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <span class="identifier">I</span>
<span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">value_of_data</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>
</pre>
<div class="table">
<a name="id867461"></a><p class="title"><b>Table&#160;1.21.&#160;Parameters</b></p>
<div class="table-contents"><table class="table" summary="Parameters">
<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">I</span></code>
</p>
</td>
<td>
<p>
Model of <a class="link" href="../concepts/associative_iterator.html" title="Associative Iterator">Associative
Iterator</a>
</p>
</td>
<td>
<p>
Operation's argument
</p>
</td>
</tr></tbody>
</table></div>
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<br class="table-break"><a name="fusion.iterator.metafunctions.value_of_data.expression_semantics"></a><h6>
<a name="id867549"></a>
<a class="link" href="value_of_data.html#fusion.iterator.metafunctions.value_of_data.expression_semantics">Expression
Semantics</a>
</h6>
<pre class="programlisting"><a class="link" href="value_of_data.html" title="value_of_data"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_of_data</span></code></a><span class="special">&lt;</span><span class="identifier">I</span><span class="special">&gt;::</span><span class="identifier">type</span>
</pre>
<p>
<span class="bold"><strong>Return type</strong></span>: Any type
</p>
<p>
<span class="bold"><strong>Semantics</strong></span>: Returns the type of the data
property associated with the element referenced by an associative iterator
<code class="computeroutput"><span class="identifier">I</span></code>.
</p>
<a name="fusion.iterator.metafunctions.value_of_data.header"></a><h6>
<a name="id867621"></a>
<a class="link" href="value_of_data.html#fusion.iterator.metafunctions.value_of_data.header">Header</a>
</h6>
<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">iterator</span><span class="special">/</span><span class="identifier">value_of_data</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">value_of_data</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<a name="fusion.iterator.metafunctions.value_of_data.example"></a><h6>
<a name="id867729"></a>
<a class="link" href="value_of_data.html#fusion.iterator.metafunctions.value_of_data.example">Example</a>
</h6>
<pre class="programlisting"><span class="keyword">typedef</span> <a class="link" href="../../container/map.html" title="map"><code class="computeroutput"><span class="identifier">map</span></code></a><span class="special">&lt;</span><a class="link" href="../../support/pair.html" title="pair"><code class="computeroutput"><span class="identifier">pair</span></code></a><span class="special">&lt;</span><span class="keyword">float</span><span class="special">,</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">vec</span><span class="special">;</span>
<span class="keyword">typedef</span> <a class="link" href="../../sequence/intrinsic/metafunctions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></code></a><span class="special">&lt;</span><span class="identifier">vec</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">first</span><span class="special">;</span>
<span class="identifier">BOOST_MPL_ASSERT</span><span class="special">((</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">is_same</span><span class="special">&lt;</span><a class="link" href="value_of_data.html" title="value_of_data"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_of_data</span></code></a><span class="special">&lt;</span><span class="identifier">first</span><span class="special">&gt;::</span><span class="identifier">type</span><span class="special">,</span> <span class="keyword">int</span><span class="special">&gt;));</span>
</pre>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2001-2007 Joel de Guzman, Dan Marsden, Tobias
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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