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<h1>Functors</h1> </div>
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<p>Functors are copyable types that define operator()(). <a href="#_details">More...</a></p>
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Classes</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1functor__base.html">sigc::functor_base</a></td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">A hint to the compiler. <a href="structsigc_1_1functor__base.html#_details">More...</a><br/></td></tr>
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Modules</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__slot.html">Slots</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p>Slots are type-safe representations of callback methods and functions. </p>
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<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__ptr__fun.html">ptr_fun()</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p><a class="elRef" doxygen="libstdc++.tag:http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a01196.html#gac7139c6dea6421abef136a026f6c071b">ptr_fun()</a> is used to convert a pointer to a function to a functor. </p>
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<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__mem__fun.html">mem_fun()</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p><a class="elRef" doxygen="libstdc++.tag:http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a01197.html#ga58aa3b67eba2b8219e7aec7d4cdebcdb">mem_fun()</a> is used to convert a pointer to a method to a functor. </p>
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Defines</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__sigcfunctors.html#ga93b6ee8815d90adccfdceed72bcda577">SIGC_FUNCTORS_HAVE_RESULT_TYPE</a></td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">If you want to mix functors from a different library with libsigc++ and these functors define <code>result_type</code> simply use this macro inside namespace sigc like so: <a href="#ga93b6ee8815d90adccfdceed72bcda577"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__sigcfunctors.html#ga7a6f5575dc0b0ea896889c782721f6be">SIGC_FUNCTOR_TRAIT</a>(T_functor, T_return)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">If you want to mix functors from a different library with libsigc++ and these functors don't define <code>result_type</code> use this macro inside namespace sigc to expose the return type of the functors like so: <a href="#ga7a6f5575dc0b0ea896889c782721f6be"></a><br/></td></tr>
<tr><td colspan="2"><h2><a name="func-members"></a>
Functions</h2></td></tr>
<tr><td class="memTemplParams" colspan="2">template<class T_action , class T_functor > </td></tr>
<tr><td class="memTemplItemLeft" align="right" valign="top">void </td><td class="memTemplItemRight" valign="bottom"><a class="el" href="group__sigcfunctors.html#gadab29aed05524743da16319da4430541">sigc::visit_each</a> (const T_action& _A_action, const T_functor& _A_functor)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">This function performs a functor on each of the targets of a functor. <a href="#gadab29aed05524743da16319da4430541"></a><br/></td></tr>
<tr><td class="memTemplParams" colspan="2"><a class="anchor" id="ga5c455eda401dee43de931c24ad45d445"></a><!-- doxytag: member="sigcfunctors::visit_each_type" ref="ga5c455eda401dee43de931c24ad45d445" args="(const T_action &_A_action, const T_functor &_A_functor)" -->
template <class T_type , class T_action , class T_functor > </td></tr>
<tr><td class="memTemplItemLeft" align="right" valign="top">void </td><td class="memTemplItemRight" valign="bottom"><a class="el" href="group__sigcfunctors.html#ga5c455eda401dee43de931c24ad45d445">sigc::visit_each_type</a> (const T_action& _A_action, const T_functor& _A_functor)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">This function performs a functor on each of the targets of a functor limited to a restricted type. <br/></td></tr>
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<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Functors are copyable types that define operator()(). </p>
<p>Types that define operator()() overloads with different return types are referred to as multi-type functors. Multi-type functors are only partially supported in libsigc++.</p>
<p>Closures are functors that store all information needed to invoke a callback from operator()().</p>
<p>Adaptors are functors that alter the signature of a functor's operator()().</p>
<p>libsigc++ defines numerous functors, closures and adaptors. Since libsigc++ is a callback libaray, most functors are also closures. The documentation doesn't distinguish between functors and closures.</p>
<p>The basic functor types libsigc++ provides are created with <a class="elRef" doxygen="libstdc++.tag:http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a01196.html#gac7139c6dea6421abef136a026f6c071b">ptr_fun()</a> and <a class="elRef" doxygen="libstdc++.tag:http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a01197.html#ga58aa3b67eba2b8219e7aec7d4cdebcdb">mem_fun()</a> and can be converted into slots implicitly. The set of adaptors that ships with libsigc++ is documented in the <a class="el" href="group__adaptors.html">Adaptors</a> module. </p>
<hr/><h2>Define Documentation</h2>
<a class="anchor" id="ga7a6f5575dc0b0ea896889c782721f6be"></a><!-- doxytag: member="functor_trait.h::SIGC_FUNCTOR_TRAIT" ref="ga7a6f5575dc0b0ea896889c782721f6be" args="(T_functor, T_return)" -->
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<td class="memname">#define SIGC_FUNCTOR_TRAIT</td>
<td>(</td>
<td class="paramtype"> </td>
<td class="paramname">T_functor, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"> </td>
<td class="paramname">T_return </td>
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<td>)</td>
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<p>If you want to mix functors from a different library with libsigc++ and these functors don't define <code>result_type</code> use this macro inside namespace sigc to expose the return type of the functors like so: </p>
<div class="fragment"><pre class="fragment"> <span class="keyword">namespace </span>sigc {
<a class="code" href="group__sigcfunctors.html#ga7a6f5575dc0b0ea896889c782721f6be" title="If you want to mix functors from a different library with libsigc++ and these functors don&#39;t defi...">SIGC_FUNCTOR_TRAIT</a>(first_functor_type, return_type_of_first_functor_type)
<a class="code" href="group__sigcfunctors.html#ga7a6f5575dc0b0ea896889c782721f6be" title="If you want to mix functors from a different library with libsigc++ and these functors don&#39;t defi...">SIGC_FUNCTOR_TRAIT</a>(second_functor_type, return_type_of_second_functor_type)
...
}
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<a class="anchor" id="ga93b6ee8815d90adccfdceed72bcda577"></a><!-- doxytag: member="functor_trait.h::SIGC_FUNCTORS_HAVE_RESULT_TYPE" ref="ga93b6ee8815d90adccfdceed72bcda577" args="" -->
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<td class="memname">#define SIGC_FUNCTORS_HAVE_RESULT_TYPE</td>
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<p>If you want to mix functors from a different library with libsigc++ and these functors define <code>result_type</code> simply use this macro inside namespace sigc like so: </p>
<div class="fragment"><pre class="fragment"> <span class="keyword">namespace </span>sigc { <a class="code" href="group__sigcfunctors.html#ga93b6ee8815d90adccfdceed72bcda577" title="If you want to mix functors from a different library with libsigc++ and these functors define result_...">SIGC_FUNCTORS_HAVE_RESULT_TYPE</a> }
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<hr/><h2>Function Documentation</h2>
<a class="anchor" id="gadab29aed05524743da16319da4430541"></a><!-- doxytag: member="sigc::visit_each" ref="gadab29aed05524743da16319da4430541" args="(const T_action &_A_action, const T_functor &_A_functor)" -->
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template <class T_action , class T_functor > </div>
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<td class="memname">void sigc::visit_each </td>
<td>(</td>
<td class="paramtype">const T_action & </td>
<td class="paramname"> <em>_A_action</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">const T_functor & </td>
<td class="paramname"> <em>_A_functor</em> </td>
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<p>This function performs a functor on each of the targets of a functor. </p>
<p>All unknown types just call <em>_A_action</em> on them. Add overloads that specialize the <em>T_functor</em> argument for your own functor types, so that subobjects get visited. This is needed to enable auto-disconnection support for your functor types.</p>
<dl class="user"><dt><b>Example:</b></dt><dd><div class="fragment"><pre class="fragment"> <span class="keyword">struct </span>some_functor
{
<span class="keywordtype">void</span> operator()() {}
some_possibly_sigc_trackable_derived_type some_data_member;
some_other_functor_type some_other_functor;
}
<span class="keyword">namespace </span>sigc
{
<span class="keyword">template</span> <<span class="keyword">class</span> T_action>
<span class="keywordtype">void</span> <a class="code" href="group__sigcfunctors.html#gadab29aed05524743da16319da4430541" title="This function performs a functor on each of the targets of a functor.">visit_each</a>(<span class="keyword">const</span> T_action& _A_action,
<span class="keyword">const</span> some_functor& _A_target)
{
<a class="code" href="group__sigcfunctors.html#gadab29aed05524743da16319da4430541" title="This function performs a functor on each of the targets of a functor.">visit_each</a>(_A_action, _A_target.some_data_member);
<a class="code" href="group__sigcfunctors.html#gadab29aed05524743da16319da4430541" title="This function performs a functor on each of the targets of a functor.">visit_each</a>(_A_action, _A_target.some_other_functor);
}
}
</pre></div> </dd></dl>
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