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<div class="titlepage"><div><div><h4 class="title">
<a name="fusion.iterator.functions.deref_data"></a><a class="link" href="deref_data.html" title="deref_data">deref_data</a>
</h4></div></div></div>
<a name="fusion.iterator.functions.deref_data.description"></a><h6>
<a name="id897661"></a>
<a class="link" href="deref_data.html#fusion.iterator.functions.deref_data.description">Description</a>
</h6>
<p>
Deferences the data property associated with the element referenced by
an associative iterator.
</p>
<a name="fusion.iterator.functions.deref_data.synopsis"></a><h6>
<a name="id897677"></a>
<a class="link" href="deref_data.html#fusion.iterator.functions.deref_data.synopsis">Synopsis</a>
</h6>
<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span>
<span class="keyword">typename</span> <span class="identifier">I</span>
<span class="special">></span>
<span class="keyword">typename</span> <a class="link" href="../metafunctions/deref_data.html" title="deref_data"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">deref_data</span></code></a><span class="special"><</span><span class="identifier">I</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">deref</span><span class="special">(</span><span class="identifier">I</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">i</span><span class="special">);</span>
</pre>
<div class="table">
<a name="id897778"></a><p class="title"><b>Table 1.8. 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>
</div>
<br class="table-break"><a name="fusion.iterator.functions.deref_data.expression_semantics"></a><h6>
<a name="id897868"></a>
<a class="link" href="deref_data.html#fusion.iterator.functions.deref_data.expression_semantics">Expression
Semantics</a>
</h6>
<pre class="programlisting"><a class="link" href="deref_data.html" title="deref_data"><code class="computeroutput"><span class="identifier">deref_data</span></code></a><span class="special">(</span><span class="identifier">i</span><span class="special">);</span>
</pre>
<p>
<span class="bold"><strong>Return type</strong></span>: <code class="computeroutput"><a class="link" href="../metafunctions/deref_data.html" title="deref_data"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">deref_data</span></code></a><span class="special"><</span><span class="identifier">I</span><span class="special">>::</span><span class="identifier">type</span></code>
</p>
<p>
<span class="bold"><strong>Semantics</strong></span>: Dereferences 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.functions.deref_data.header"></a><h6>
<a name="id897965"></a>
<a class="link" href="deref_data.html#fusion.iterator.functions.deref_data.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">iterator</span><span class="special">/</span><span class="identifier">deref_data</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">deref_data</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
</pre>
<a name="fusion.iterator.functions.deref_data.example"></a><h6>
<a name="id898073"></a>
<a class="link" href="deref_data.html#fusion.iterator.functions.deref_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"><</span><a class="link" href="../../support/pair.html" title="pair"><code class="computeroutput"><span class="identifier">pair</span></code></a><span class="special"><</span><span class="keyword">float</span><span class="special">,</span><span class="keyword">int</span><span class="special">&></span> <span class="special">></span> <span class="identifier">map</span><span class="special">;</span>
<span class="keyword">int</span> <span class="identifier">i</span><span class="special">(</span><span class="number">0</span><span class="special">);</span>
<span class="identifier">map</span> <span class="identifier">m</span><span class="special">(</span><span class="number">1.0f</span><span class="special">,</span><span class="identifier">i</span><span class="special">);</span>
<span class="identifier">assert</span><span class="special">(</span><a class="link" href="deref_data.html" title="deref_data"><code class="computeroutput"><span class="identifier">deref_data</span></code></a><span class="special">(</span><a class="link" href="../../sequence/intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">m</span><span class="special">))</span> <span class="special">==</span> <span class="number">0</span><span class="special">);</span>
<span class="identifier">assert</span><span class="special">(&(</span><a class="link" href="deref_data.html" title="deref_data"><code class="computeroutput"><span class="identifier">deref_data</span></code></a><span class="special">(</span><a class="link" href="../../sequence/intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">m</span><span class="special">)))</span> <span class="special">==</span> <span class="special">&</span><span class="identifier">i</span><span class="special">);</span>
</pre>
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