<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>Class function_base</title> <link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> <link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> <link rel="up" href="../function/reference.html#header.boost.function_hpp" title="Header <boost/function.hpp>"> <link rel="prev" href="bad_function_call.html" title="Class bad_function_call"> <link rel="next" href="functionN.html" title="Class template functionN"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr> <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> <td align="center"><a href="../../../index.html">Home</a></td> <td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> <td align="center"><a href="../../../more/index.htm">More</a></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="bad_function_call.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../function/reference.html#header.boost.function_hpp"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="functionN.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> </div> <div class="refentry"> <a name="boost.function_base"></a><div class="titlepage"></div> <div class="refnamediv"> <h2><span class="refentrytitle">Class function_base</span></h2> <p>boost::function_base — The common base class for all Boost.Function objects. Objects of type function_base may not be created directly.</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: <<a class="link" href="../function/reference.html#header.boost.function_hpp" title="Header <boost/function.hpp>">boost/function.hpp</a>> </span> <span class="keyword">class</span> <a class="link" href="function_base.html" title="Class function_base">function_base</a> <span class="special">{</span> <span class="keyword">public</span><span class="special">:</span> <span class="comment">// <a class="link" href="function_base.html#idm45507091539808-bb">capacity</a></span> <span class="keyword">bool</span> <a class="link" href="function_base.html#idm45507135880240-bb"><span class="identifier">empty</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> <span class="comment">// <a class="link" href="function_base.html#idm45507108869776-bb">target access</a></span> <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="identifier">Functor</span><span class="special">*</span> <a class="link" href="function_base.html#idm45507098780240-bb"><span class="identifier">target</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="keyword">const</span> <span class="identifier">Functor</span><span class="special">*</span> <a class="link" href="function_base.html#idm45507105418272-bb"><span class="identifier">target</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="keyword">bool</span> <a class="link" href="function_base.html#idm45507163510272-bb"><span class="identifier">contains</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Functor</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">type_info</span><span class="special">&</span> <a class="link" href="function_base.html#idm45507157042800-bb"><span class="identifier">target_type</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="idm45555352239344"></a><h2>Description</h2> <div class="refsect2"> <a name="idm45555352238928"></a><h3> <a name="idm45507091539808-bb"></a><code class="computeroutput">function_base</code> capacity</h3> <div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> <pre class="literallayout"><span class="keyword">bool</span> <a name="idm45507135880240-bb"></a><span class="identifier">empty</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> <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> <code class="computeroutput">false</code> if <code class="computeroutput">this</code> has a target, and <code class="computeroutput">true</code> otherwise.</td> </tr> <tr> <td><p><span class="term">Throws:</span></p></td> <td>Will not throw.</td> </tr> </tbody> </table></div> </li></ol></div> </div> <div class="refsect2"> <a name="idm45555352227536"></a><h3> <a name="idm45507108869776-bb"></a><code class="computeroutput">function_base</code> target access</h3> <div class="orderedlist"><ol class="orderedlist" type="1"> <li class="listitem"> <pre class="literallayout"><a name="idm45507094120720-bb"></a><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="identifier">Functor</span><span class="special">*</span> <a name="idm45507098780240-bb"></a><span class="identifier">target</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="keyword">const</span> <span class="identifier">Functor</span><span class="special">*</span> <a name="idm45507105418272-bb"></a><span class="identifier">target</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> <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>If <code class="computeroutput">this</code> stores a target of type <code class="computeroutput">Functor</code>, returns the address of the target. Otherwise, returns the NULL pointer.</td> </tr> <tr> <td><p><span class="term">Throws:</span></p></td> <td>Will not throw.</td> </tr> </tbody> </table></div> </li> <li class="listitem"> <pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Functor<span class="special">></span> <span class="keyword">bool</span> <a name="idm45507163510272-bb"></a><span class="identifier">contains</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Functor</span><span class="special">&</span> f<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> <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> <code class="computeroutput">true</code> if <code class="computeroutput">this-><a class="link" href="function_base.html#idm45507094120720-bb">target</a><Functor>()</code> is non-NULL and <code class="computeroutput"><a class="link" href="function_equal.html" title="Function template function_equal">function_equal</a>(*(this->target<Functor>()), f)</code> </td> </tr></tbody> </table></div> </li> <li class="listitem"> <pre class="literallayout"><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">type_info</span><span class="special">&</span> <a name="idm45507157042800-bb"></a><span class="identifier">target_type</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> <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> <code class="computeroutput">typeid</code> of the target function object, or <code class="computeroutput">typeid(void)</code> if <code class="computeroutput">this-><a class="link" href="function_base.html#idm45507135880240-bb">empty</a>()</code>.</td> </tr> <tr> <td><p><span class="term">Throws:</span></p></td> <td>Will not throw.</td> </tr> </tbody> </table></div> </li> </ol></div> </div> </div> </div> <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> <td align="left"></td> <td align="right"><div class="copyright-footer">Copyright © 2001-2004 Douglas Gregor<p>Use, modification and distribution is subject to the Boost Software License, Version 1.0. (See accompanying file <code class="filename">LICENSE_1_0.txt</code> 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> </div></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="bad_function_call.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../function/reference.html#header.boost.function_hpp"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="functionN.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> </div> </body> </html>