335 lines
28 KiB
HTML
335 lines
28 KiB
HTML
<!DOCTYPE html>
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<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
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<head><meta http-equiv="x-ua-compatible" content="ie=edge">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<title>std::function</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_utility_functional_function skin-cppreference2 action-view cpp-navbar">
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<div id="cpp-content-base">
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>function</h1>
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-utility.html">utility</a>‎ | <a href="cpp-utility-functional.html">functional</a></span></div>
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<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
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<table class="t-dcl-begin">
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<div>定义于头文件 <code><a href="cpp-header-functional.html"><functional></a></code></div>
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</td>
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<td></td>
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<td></td>
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<tr class="t-dcl t-since-cxx11">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> <span class="sy1">></span><br />
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<span class="kw1">class</span> function<span class="sy4">;</span> <span class="coMULTI">/* 未定义 */</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> R, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw1">class</span> function<span class="sy1"><</span>R<span class="br0">(</span>Args...<span class="br0">)</span><span class="sy1">></span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<p>类模板 <code>std::function</code> 是通用多态函数包装器。 <code>std::function</code> 的实例能存储、复制及调用任何<a href="cpp-named_req-CopyConstructible.html"><span style="font-style:italic">可复制构造</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(CopyConstructible)</span></a> 的<a href="cpp-named_req-Callable.html"><span style="font-style:italic">可调用</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Callable)</span></a> <i>目标</i>——函数、 <a href="cpp-language-lambda.html">lambda 表达式</a>、 <a href="cpp-utility-functional-bind.html">bind 表达式</a>或其他函数对象，还有指向成员函数指针和指向数据成员指针。</p>
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<p>存储的可调用对象被称为 <code>std::function</code> 的<i>目标</i>。若 <code>std::function</code> 不含目标，则称它为<i>空</i>。调用<i>空</i> <code>std::function</code> 的<i>目标</i>导致抛出 <span class="t-lc"><a href="cpp-utility-functional-bad_function_call.html">std::bad_function_call</a></span> 异常。</p>
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<p><code>std::function</code> 满足<a href="cpp-named_req-CopyConstructible.html"><span style="font-style:italic">可复制构造</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(CopyConstructible)</span></a> 和<a href="cpp-named_req-CopyAssignable.html"><span style="font-style:italic">可复制赋值</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(CopyAssignable)</span></a> 。</p>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">成员类型</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc-hitem">
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<td>类型</td>
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<td>定义</td>
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</tr>
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<tr class="t-dsc">
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<td><code>result_type</code></td>
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<td><code>R</code></td>
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</tr>
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<tr class="t-dsc">
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<td><code>argument_type</code><span class="t-mark">(C++17 中弃用)</span><span class="t-mark-rev t-until-cxx20">(C++20 中移除)</span></td>
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<td>若 <span class="t-c"><span class="mw-geshi cpp source-cpp">sizeof...<span class="br0">(</span>Args<span class="br0">)</span><span class="sy1">==</span><span class="nu0">1</span></span></span> 且 <code>T</code> 是 <code>Args...</code> 中首个且唯一的类型，则为 <code>T</code></td>
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</tr>
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<tr class="t-dsc">
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<td><code>first_argument_type</code><span class="t-mark">(C++17 中弃用)</span><span class="t-mark-rev t-until-cxx20">(C++20 中移除)</span></td>
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<td>若 <span class="t-c"><span class="mw-geshi cpp source-cpp">sizeof...<span class="br0">(</span>Args<span class="br0">)</span><span class="sy1">==</span><span class="nu0">2</span></span></span> 且 <code>T1</code> 是 <code>Args...</code> 中二个类型的第一个，则为 <code>T1</code></td>
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</tr>
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<tr class="t-dsc">
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<td><code>second_argument_type</code><span class="t-mark">(C++17 中弃用)</span><span class="t-mark-rev t-until-cxx20">(C++20 中移除)</span></td>
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<td>若 <span class="t-c"><span class="mw-geshi cpp source-cpp">sizeof...<span class="br0">(</span>Args<span class="br0">)</span><span class="sy1">==</span><span class="nu0">2</span></span></span> 且 <code>T2</code> 是 <code>Args...</code> 中二个类型的第二个，则为 <code>T2</code></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">成员函数</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
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<div><a href="cpp-utility-functional-function-function.html"><span class="t-lines"><span>(构造函数)</span></span></a></div>
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</div>
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</td>
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<td>构造新的 <span class="t-lc"><strong class="selflink">std::function</strong></span> 实例<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
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<div><a href="cpp-utility-functional-function-~function.html"><span class="t-lines"><span>(析构函数)</span></span></a></div>
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</div>
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</td>
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<td>析构 <span class="t-lc"><strong class="selflink">std::function</strong></span> 实例<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-operator=.html"><span class="t-lines"><span>operator=</span></span></a></div>
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</div>
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</td>
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<td>为内容赋值<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-swap.html"><span class="t-lines"><span>swap</span></span></a></div>
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</div>
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</td>
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<td>交换内容<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-assign.html"><span class="t-lines"><span>assign</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-until-cxx17">(C++17 中移除)</span></span></span></div>
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</div>
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</td>
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<td>为内容赋值一个新的目标<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-operator_bool.html"><span class="t-lines"><span>operator bool</span></span></a></div>
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</div>
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</td>
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<td>检查是否包含了有效的目标<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-operator().html"><span class="t-lines"><span>operator()</span></span></a></div>
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</div>
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</td>
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<td>调用其目标<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr>
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<td colspan="2">
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<h5><span class="mw-headline" id=".E7.9B.AE.E6.A0.87.E8.AE.BF.E9.97.AE">目标访问</span></h5>
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</td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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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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</div>
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</td>
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<td>获得 <span class="t-lc"><strong class="selflink">std::function</strong></span> 所存储的目标的<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">typeid</span></span></span><br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-target.html"><span class="t-lines"><span>target</span></span></a></div>
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</div>
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</td>
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<td>获得指向 <span class="t-lc"><strong class="selflink">std::function</strong></span> 所存储的目标的指针<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E9.9D.9E.E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">非成员函数</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-swap2.html"><span class="t-lines"><span>std::swap<span class="t-dsc-small">(std::function)</span></span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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</div>
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</td>
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<td>特化 <span class="t-lc"><a href="cpp-algorithm-swap.html">std::swap</a></span> 算法<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-operator_cmp.html"><span class="t-lines"><span>operator==</span><span>operator!=</span></span></a></div>
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<div><span class="t-lines"><span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 中移除)</span></span></span></div>
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</div>
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</td>
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<td>比较 <span class="t-lc"><strong class="selflink">std::function</strong></span> 和 <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr</span></span><br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E8.BE.85.E5.8A.A9.E7.B1.BB">辅助类</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-utility-functional-function-uses_allocator.html"><span class="t-lines"><span>std::uses_allocator<span class="t-dsc-small"><std::function></span></span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span> <span class="t-mark-rev t-until-cxx17">(C++17 前)</span></span></span></div>
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</div>
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</td>
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<td>特化 <span class="t-lc"><a href="cpp-memory-uses_allocator.html">std::uses_allocator</a></span> 类型特性<br />
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<span class="t-mark">(类模板特化)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E6.8E.A8.E5.AF.BC.E6.8C.87.E5.BC.95.28C.2B.2B17_.E8.B5.B7.29"><a href="cpp-utility-functional-function-deduction_guides.html">推导指引</a><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></span></h3>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">注解</span></h3>
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<p>当结果类型为引用的 <code>std::function</code> 从无尾随返回类型的 lambda 表达式初始化时需要留心。由于 auto 推导的起效方式，这种 lambda 表达式将始终返回纯右值。故而结果引用将始终绑定到生命期在 <code>std::function::operator()</code> 返回时结束的临时量。</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1">std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">const</span> <span class="kw4">int</span><span class="sy3">&</span><span class="br0">(</span><span class="br0">)</span><span class="sy1">></span> F<span class="br0">(</span><span class="br0">[</span><span class="br0">]</span><span class="br0">{</span> <span class="kw1">return</span> <span class="nu0">42</span><span class="sy4">;</span> <span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw4">int</span> x <span class="sy1">=</span> F<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// 未定义行为： F() 的结果是悬垂引用</span></pre></div>
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</div>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
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<div class="t-example">
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<div class="t-example-live-link"></div>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="co2">#include <functional></span>
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<span class="co2">#include <iostream></span>
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<span class="kw1">struct</span> Foo <span class="br0">{</span>
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Foo<span class="br0">(</span><span class="kw4">int</span> num<span class="br0">)</span> <span class="sy4">:</span> num_<span class="br0">(</span>num<span class="br0">)</span> <span class="br0">{</span><span class="br0">}</span>
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<span class="kw4">void</span> print_add<span class="br0">(</span><span class="kw4">int</span> i<span class="br0">)</span> <span class="kw4">const</span> <span class="br0">{</span> <a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> num_<span class="sy2">+</span>i <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="br0">}</span>
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<span class="kw4">int</span> num_<span class="sy4">;</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="kw4">void</span> print_num<span class="br0">(</span><span class="kw4">int</span> i<span class="br0">)</span>
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<span class="br0">{</span>
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<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="kw1">struct</span> PrintNum <span class="br0">{</span>
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<span class="kw4">void</span> operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span><span class="kw4">int</span> i<span class="br0">)</span> <span class="kw4">const</span>
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<span class="br0">{</span>
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<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
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<span class="br0">{</span>
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<span class="co1">// 存储自由函数</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> f_display <span class="sy1">=</span> print_num<span class="sy4">;</span>
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f_display<span class="br0">(</span><span class="sy2">-</span><span class="nu0">9</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储 lambda</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="br0">)</span><span class="sy1">></span> f_display_42 <span class="sy1">=</span> <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span> print_num<span class="br0">(</span><span class="nu0">42</span><span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span><span class="sy4">;</span>
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f_display_42<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储到 std::bind 调用的结果</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="br0">)</span><span class="sy1">></span> f_display_31337 <span class="sy1">=</span> <a href="cpp-utility-functional-bind.html"><span class="kw1052">std::<span class="me2">bind</span></span></a><span class="br0">(</span>print_num, <span class="nu0">31337</span><span class="br0">)</span><span class="sy4">;</span>
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f_display_31337<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储到成员函数的调用</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="kw4">const</span> Foo<span class="sy3">&</span>, <span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> f_add_display <span class="sy1">=</span> <span class="sy3">&</span>Foo<span class="sy4">::</span><span class="me2">print_add</span><span class="sy4">;</span>
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<span class="kw4">const</span> Foo foo<span class="br0">(</span><span class="nu0">314159</span><span class="br0">)</span><span class="sy4">;</span>
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f_add_display<span class="br0">(</span>foo, <span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span>
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f_add_display<span class="br0">(</span><span class="nu0">314159</span>, <span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储到数据成员访问器的调用</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">int</span><span class="br0">(</span>Foo <span class="kw4">const</span><span class="sy3">&</span><span class="br0">)</span><span class="sy1">></span> f_num <span class="sy1">=</span> <span class="sy3">&</span>Foo<span class="sy4">::</span><span class="me2">num_</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"num_: "</span> <span class="sy1"><<</span> f_num<span class="br0">(</span>foo<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
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<span class="co1">// 存储到成员函数及对象的调用</span>
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<span class="kw1">using</span> std<span class="sy4">::</span><span class="me2">placeholders</span><span class="sy4">::</span>_1<span class="sy4">;</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> f_add_display2 <span class="sy1">=</span> <a href="cpp-utility-functional-bind.html"><span class="kw1052">std::<span class="me2">bind</span></span></a><span class="br0">(</span> <span class="sy3">&</span>Foo<span class="sy4">::</span><span class="me2">print_add</span>, foo, _1 <span class="br0">)</span><span class="sy4">;</span>
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f_add_display2<span class="br0">(</span><span class="nu0">2</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储到成员函数和对象指针的调用</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> f_add_display3 <span class="sy1">=</span> <a href="cpp-utility-functional-bind.html"><span class="kw1052">std::<span class="me2">bind</span></span></a><span class="br0">(</span> <span class="sy3">&</span>Foo<span class="sy4">::</span><span class="me2">print_add</span>, <span class="sy3">&</span>foo, _1 <span class="br0">)</span><span class="sy4">;</span>
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f_add_display3<span class="br0">(</span><span class="nu0">3</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 存储到函数对象的调用</span>
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|
std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">void</span><span class="br0">(</span><span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> f_display_obj <span class="sy1">=</span> PrintNum<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
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f_display_obj<span class="br0">(</span><span class="nu0">18</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw4">auto</span> factorial <span class="sy1">=</span> <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">int</span> n<span class="br0">)</span> <span class="br0">{</span>
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<span class="co1">// 存储 lambda 对象以模拟“递归 lambda ”，注意额外开销</span>
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std<span class="sy4">::</span><span class="me2">function</span><span class="sy1"><</span><span class="kw4">int</span><span class="br0">(</span><span class="kw4">int</span><span class="br0">)</span><span class="sy1">></span> fac <span class="sy1">=</span> <span class="br0">[</span><span class="sy3">&</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">int</span> n<span class="br0">)</span><span class="br0">{</span> <span class="kw1">return</span> <span class="br0">(</span>n <span class="sy1"><</span> <span class="nu0">2</span><span class="br0">)</span> <span class="sy4">?</span> <span class="nu0">1</span> <span class="sy4">:</span> n<span class="sy2">*</span>fac<span class="br0">(</span>n<span class="sy2">-</span><span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span><span class="sy4">;</span>
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<span class="co1">// note that "auto fac = [&](int n){...};" does not work in recursive calls</span>
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<span class="kw1">return</span> fac<span class="br0">(</span>n<span class="br0">)</span><span class="sy4">;</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> i<span class="br0">{</span><span class="nu0">5</span><span class="br0">}</span><span class="sy4">;</span> i <span class="sy3">!</span><span class="sy1">=</span> <span class="nu0">8</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span> <span class="br0">{</span> <a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i <span class="sy1"><<</span> <span class="st0">"! = "</span> <span class="sy1"><<</span> factorial<span class="br0">(</span>i<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">"; "</span><span class="sy4">;</span> <span class="br0">}</span>
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<span class="br0">}</span></pre></div>
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</div>
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<p>可能的输出：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
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<pre class="de1">-9
|
|
42
|
|
31337
|
|
314160
|
|
314160
|
|
num_: 314159
|
|
314161
|
|
314162
|
|
18
|
|
5! = 120; 6! = 720; 7! = 5040;</pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
|
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<td>
|
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<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-move_only_function.html"><span class="t-lines"><span>move_only_function</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx23">(C++23)</span></span></span></div>
|
|
</div>
|
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</td>
|
|
<td>包装具有指定函数调用签名的任意类型的可调用对象<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-bad_function_call.html"><span class="t-lines"><span>bad_function_call</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
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</div>
|
|
</td>
|
|
<td>调用空的 <span class="t-lc"><strong class="selflink">std::function</strong></span> 时抛出的异常<br />
|
|
<span class="t-mark">(类)</span></td>
|
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</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-mem_fn.html"><span class="t-lines"><span>mem_fn</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
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</div>
|
|
</td>
|
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<td>从成员指针创建出函数对象<br />
|
|
<span class="t-mark">(函数模板)</span></td>
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</tr>
|
|
</table>
|
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</div>
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<div class="visualClear"></div>
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</div>
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</div>
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</div>
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</body>
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</html>
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