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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::function&lt;R(Args...)&gt;::</span>target</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-utility.html">utility</a>&lrm; | <a href="cpp-utility-functional.html">functional</a>&lrm; | <a href="cpp-utility-functional-function.html">function</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T <span class="sy1">&gt;</span><br />
T<span class="sy2">*</span> target<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T <span class="sy1">&gt;</span><br />
<span class="kw4">const</span> T<span class="sy2">*</span> target<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#36820;&#22238;&#25351;&#21521;&#23384;&#20648;&#30340;&#21487;&#35843;&#29992;&#20989;&#25968;&#30446;&#26631;&#30340;&#25351;&#38024;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<p>&#65288;&#26080;&#65289;</p>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">target_type<span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> <span class="kw1">typeid</span><span class="br0">(</span>T<span class="br0">)</span></span></span> &#21017;&#20026;&#25351;&#21521;&#23384;&#20648;&#30340;&#20989;&#25968;&#30340;&#25351;&#38024;&#65292;&#21542;&#21017;&#20026;&#31354;&#25351;&#38024;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;functional&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw4">int</span> f<span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> <span class="nu0">1</span><span class="sy4">;</span> <span class="br0">}</span>
<span class="kw4">int</span> g<span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> <span class="nu0">2</span><span class="sy4">;</span> <span class="br0">}</span>
<span class="kw4">void</span> test<span class="br0">(</span><a href="cpp-utility-functional-function.html"><span class="kw1059">std::<span class="me2">function</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span> <span class="kw4">const</span><span class="sy3">&amp;</span> arg<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;test function: &quot;</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>arg.<span class="me1">target</span><span class="sy1">&lt;</span><a href="cpp-utility-functional-plus.html"><span class="kw1029">std::<span class="me2">plus</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;&gt;</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;it is plus<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>arg.<span class="me1">target</span><span class="sy1">&lt;</span><a href="cpp-utility-functional-minus.html"><span class="kw1030">std::<span class="me2">minus</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;&gt;</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;it is minus<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="kw4">int</span> <span class="br0">(</span><span class="sy2">*</span><span class="kw4">const</span><span class="sy2">*</span> ptr<span class="br0">)</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span> <span class="sy1">=</span> arg.<span class="me1">target</span><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="sy2">*</span><span class="br0">)</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>ptr <span class="sy3">&amp;&amp;</span> <span class="sy2">*</span>ptr <span class="sy1">==</span> f<span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;it is the function f<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>ptr <span class="sy3">&amp;&amp;</span> <span class="sy2">*</span>ptr <span class="sy1">==</span> g<span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;it is the function g<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
test<span class="br0">(</span><a href="cpp-utility-functional-function.html"><span class="kw1059">std::<span class="me2">function</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span><span class="br0">(</span><a href="cpp-utility-functional-plus.html"><span class="kw1029">std::<span class="me2">plus</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
test<span class="br0">(</span><a href="cpp-utility-functional-function.html"><span class="kw1059">std::<span class="me2">function</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span><span class="br0">(</span><a href="cpp-utility-functional-minus.html"><span class="kw1030">std::<span class="me2">minus</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
test<span class="br0">(</span><a href="cpp-utility-functional-function.html"><span class="kw1059">std::<span class="me2">function</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span><span class="br0">(</span>f<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
test<span class="br0">(</span><a href="cpp-utility-functional-function.html"><span class="kw1059">std::<span class="me2">function</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">&gt;</span><span class="br0">(</span>g<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">test function: it is plus
test function: it is minus
test function: it is the function f
test function: it is the function g</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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<div><a href="cpp-utility-functional-function-target_type.html"><span class="t-lines"><span>target_type</span></span></a></div>
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<td>&#33719;&#24471; <span class="t-lc"><a href="cpp-utility-functional-function.html">std::function</a></span> &#25152;&#23384;&#20648;&#30340;&#30446;&#26631;&#30340;<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">typeid</span></span></span><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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