boost_1_45_0/doc/html/CallableTransform.html

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<a name="CallableTransform"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle">Concept CallableTransform</span></h2>
<p>CallableTransform</p>
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<div class="refsect1">
<a name="id2456049"></a><h2>Description</h2>
<p>
      A CallableTransform is a function type or a function
      pointer type where the return type Fn is a
      PolymorphicFunctionObject and the arguments are
      Transforms. is_callable&lt; Fn &gt;::value
      must be true. The CallableTransform, when applied,
      has the effect of invoking the polymorphic function
      object Fn, passing as arguments the result(s)
      of applying transform(s) Tn.
    </p>
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<div class="refsect1">
<a name="id2456060"></a><h2>Associated types</h2>
<div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem">
<p><span class="bold"><strong>result_type</strong></span></p>
<pre class="literallayout">boost::result_of&lt;Fn(Transform&lt;Tn, Expr, State, Data&gt;::result_type...)&gt;::type</pre>
<p>
      </p>
<p>The result of applying the CallableTransform.</p>
<p>
    </p>
</li></ul></div>
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<div class="refsect1">
<a name="id2456083"></a><h2>Notation</h2>
<div class="variablelist"><dl>
<dt><span class="term">Fn</span></dt>
<dd>A type playing the role of polymorphic-function-object-type in the <a class="link" href="CallableTransform.html" title="Concept CallableTransform">CallableTransform</a> concept.</dd>
<dt><span class="term">Tn</span></dt>
<dd>A type playing the role of transform-type in the <a class="link" href="CallableTransform.html" title="Concept CallableTransform">CallableTransform</a> concept.</dd>
<dt><span class="term">Expr</span></dt>
<dd>A type playing the role of expression-type in the <a class="link" href="CallableTransform.html" title="Concept CallableTransform">CallableTransform</a> concept.</dd>
<dt><span class="term">State</span></dt>
<dd>A type playing the role of state-type in the <a class="link" href="CallableTransform.html" title="Concept CallableTransform">CallableTransform</a> concept.</dd>
<dt><span class="term">Data</span></dt>
<dd>A type playing the role of data-type in the <a class="link" href="CallableTransform.html" title="Concept CallableTransform">CallableTransform</a> concept.</dd>
<dt><span class="term"><code class="varname">fn</code></span></dt>
<dd>Object of type Fn</dd>
<dt><span class="term"><code class="varname">expr</code></span></dt>
<dd>Object of type Expr</dd>
<dt><span class="term"><code class="varname">state</code></span></dt>
<dd>Object of type State</dd>
<dt><span class="term"><code class="varname">data</code></span></dt>
<dd>Object of type Data</dd>
</dl></div>
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<div class="refsect1">
<a name="id2456197"></a><h2>Valid expressions</h2>
<div class="informaltable"><table class="table">
<colgroup>
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<thead><tr>
<th>Name</th>
<th>Expression</th>
<th>Type</th>
<th>Semantics</th>
</tr></thead>
<tbody><tr>
<td><p>Apply Transform</p></td>
<td><p>when&lt; _, Fn(Tn...)&gt;()(expr, state, data)</p></td>
<td><p><span class="type">result_type</span></p></td>
<td><p>Applies the transform.</p></td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="id2456235"></a><h2>Models</h2>
<div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"><span class="simplelist"><span class="type">boost::proto::_child(boost::proto::_left)</span></span></li></ul></div>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2008 Eric Niebler<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>)
      </p>
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