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<title>Class template reference_wrapper</title>
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<div class="refentry">
<a name="boost.reference_wrapper"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle">Class template reference_wrapper</span></h2>
<p>boost::reference_wrapper &#8212; Contains a reference to an object of type <code class="computeroutput">T</code>. </p>
</div>
<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../core/ref.html#header.boost.core.ref_hpp" title="Header &lt;boost/core/ref.hpp&gt;">boost/core/ref.hpp</a>&gt;

</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> 
<span class="keyword">class</span> <a class="link" href="reference_wrapper.html" title="Class template reference_wrapper">reference_wrapper</a> <span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
  <span class="comment">// <a class="link" href="reference_wrapper.html#boost.reference_wrappertypes">types</a></span>
  <span class="keyword">typedef</span> <span class="identifier">T</span> <a class="link" href="reference_wrapper.html#boost.reference_wrapper.type"><span class="identifier">type</span></a><span class="special">;</span>

  <span class="comment">// <a class="link" href="reference_wrapper.html#boost.reference_wrapperconstruct-copy-destruct">construct/copy/destruct</a></span>
  <span class="keyword">explicit</span> <a class="link" href="reference_wrapper.html#idp27519712-bb"><span class="identifier">reference_wrapper</span></a><span class="special">(</span><span class="identifier">T</span> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <a class="link" href="reference_wrapper.html#idp27523232-bb"><span class="identifier">reference_wrapper</span></a><span class="special">(</span><span class="identifier">T</span> <span class="special">&amp;&amp;</span><span class="special">)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span>

  <span class="comment">// <a class="link" href="reference_wrapper.html#idp27511824-bb">public member functions</a></span>
  <a class="link" href="reference_wrapper.html#idp27512384-bb"><span class="keyword">operator</span> <span class="identifier">T</span> <span class="special">&amp;</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">T</span> <span class="special">&amp;</span> <a class="link" href="reference_wrapper.html#idp27514784-bb"><span class="identifier">get</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">T</span> <span class="special">*</span> <a class="link" href="reference_wrapper.html#idp27517184-bb"><span class="identifier">get_pointer</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="idp87219712"></a><h2>Description</h2>
<p><code class="computeroutput"><a class="link" href="reference_wrapper.html" title="Class template reference_wrapper">reference_wrapper</a></code> is primarily used to "feed" references to function templates (algorithms) that take their parameter by value. It provides an implicit conversion to <code class="computeroutput">T&amp;</code>, which usually allows the function templates to work on references unmodified. </p>
<div class="refsect2">
<a name="idp87222304"></a><h3>
<a name="boost.reference_wrappertypes"></a><code class="computeroutput">reference_wrapper</code> 
        public
       types</h3>
<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
<p>
<span class="keyword">typedef</span> <span class="identifier">T</span> <a name="boost.reference_wrapper.type"></a><span class="identifier">type</span><span class="special">;</span></p>
<p>Type <code class="computeroutput">T</code>. </p>
</li></ol></div>
</div>
<div class="refsect2">
<a name="idp87229184"></a><h3>
<a name="boost.reference_wrapperconstruct-copy-destruct"></a><code class="computeroutput">reference_wrapper</code> 
        public
       construct/copy/destruct</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
<pre class="literallayout"><span class="keyword">explicit</span> <a name="idp27519712-bb"></a><span class="identifier">reference_wrapper</span><span class="special">(</span><span class="identifier">T</span> <span class="special">&amp;</span> t<span class="special">)</span><span class="special">;</span></pre>
<p>Constructs a <code class="computeroutput"><code class="computeroutput"><a class="link" href="reference_wrapper.html" title="Class template reference_wrapper">reference_wrapper</a></code></code> object that stores a reference to <code class="computeroutput">t</code>.</p>
<p>Does not throw. </p>
<p>
</p>
</li>
<li class="listitem">
<pre class="literallayout"><a name="idp27523232-bb"></a><span class="identifier">reference_wrapper</span><span class="special">(</span><span class="identifier">T</span> <span class="special">&amp;&amp;</span> t<span class="special">)</span> <span class="special">=</span> <span class="keyword">delete</span><span class="special">;</span></pre>
<p>Construction from a temporary object is disabled. </p>
<p>
</p>
</li>
</ol></div>
</div>
<div class="refsect2">
<a name="idp87247120"></a><h3>
<a name="idp27511824-bb"></a><code class="computeroutput">reference_wrapper</code> public member functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
<pre class="literallayout"><a name="idp27512384-bb"></a><span class="keyword">operator</span> <span class="identifier">T</span> <span class="special">&amp;</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>
</p>
<p>Does not throw. </p>
<p>
</p>
<div class="variablelist"><table border="0" class="variablelist compact">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term">Returns:</span></p></td>
<td><p>The stored reference. </p></td>
</tr></tbody>
</table></div>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">T</span> <span class="special">&amp;</span> <a name="idp27514784-bb"></a><span class="identifier">get</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>
</p>
<p>Does not throw. </p>
<p>
</p>
<div class="variablelist"><table border="0" class="variablelist compact">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term">Returns:</span></p></td>
<td><p>The stored reference. </p></td>
</tr></tbody>
</table></div>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">T</span> <span class="special">*</span> <a name="idp27517184-bb"></a><span class="identifier">get_pointer</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>
</p>
<p>Does not throw. </p>
<p>
</p>
<div class="variablelist"><table border="0" class="variablelist compact">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term">Returns:</span></p></td>
<td><p>A pointer to the object referenced by the stored reference. </p></td>
</tr></tbody>
</table></div>
</li>
</ol></div>
</div>
</div>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2014 Peter Dimov<br>Copyright &#169; 2014 Glen Fernandes<br>Copyright &#169; 2014 Andrey Semashev<p>
        Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost
        Software License, Version 1.0</a>.
      </p>
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