301 lines
25 KiB
HTML
301 lines
25 KiB
HTML
<!DOCTYPE html>
|
|
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
|
|
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<title>std::get(std::pair)</title>
|
|
<link rel="stylesheet" href="ext.css" />
|
|
<link rel="stylesheet" href="site_modules.css" />
|
|
</head>
|
|
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_utility_pair_get skin-cppreference2 action-view cpp-navbar">
|
|
<div id="cpp-content-base">
|
|
<div id="content"><a id="top"></a>
|
|
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>get<small>(std::pair)</small></h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-utility.html">utility</a>‎ | <a href="cpp-utility-pair.html">pair</a></span></div>
|
|
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dsc-header">
|
|
<td>
|
|
<div>定义于头文件 <code><a href="cpp-header-utility.html"><utility></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(1)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw1">typename</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1099">std::<span class="me2">tuple_element</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span><span class="sy3">&</span><br /></p>
|
|
get<span class="br0">(</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1, T2<span class="sy1">></span><span class="sy3">&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1100">std::<span class="me2">tuple_element_t</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy3">&</span><br /></p>
|
|
get<span class="br0">(</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1, T2<span class="sy1">></span><span class="sy3">&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(2)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">const</span> <span class="kw1">typename</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1099">std::<span class="me2">tuple_element</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span><span class="sy3">&</span><br /></p>
|
|
get<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> <span class="kw4">const</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1100">std::<span class="me2">tuple_element_t</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy3">&</span><br /></p>
|
|
get<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(3)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw1">typename</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1099">std::<span class="me2">tuple_element</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span><span class="sy3">&&</span><br /></p>
|
|
get<span class="br0">(</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1100">std::<span class="me2">tuple_element_t</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy3">&&</span><br /></p>
|
|
get<span class="br0">(</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody></tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(4)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">const</span> <span class="kw1">typename</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1099">std::<span class="me2">tuple_element</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span><span class="sy3">&&</span><br /></p>
|
|
get<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> I, <span class="kw1">class</span> T1, <span class="kw1">class</span> T2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> <span class="kw4">const</span> <a href="cpp-utility-tuple-tuple_element.html"><span class="kw1100">std::<span class="me2">tuple_element_t</span></span></a><span class="sy1"><</span>I, <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span> <span class="sy1">></span><span class="sy3">&&</span><br /></p>
|
|
get<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T1,T2<span class="sy1">></span><span class="sy3">&&</span> p <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> T<span class="sy3">&</span> get<span class="br0">(</span><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, U<span class="sy1">></span><span class="sy3">&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(5)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> <span class="kw4">const</span> T<span class="sy3">&</span> get<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, U<span class="sy1">></span><span class="sy3">&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(6)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> T<span class="sy3">&&</span> get<span class="br0">(</span><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, U<span class="sy1">></span><span class="sy3">&&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(7)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> <span class="kw4">const</span> T<span class="sy3">&&</span> get<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, U<span class="sy1">></span><span class="sy3">&&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(8)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> T<span class="sy3">&</span> get<span class="br0">(</span><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>U, T<span class="sy1">></span><span class="sy3">&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(9)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> <span class="kw4">const</span> T<span class="sy3">&</span> get<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>U, T<span class="sy1">></span><span class="sy3">&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(10)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> T<span class="sy3">&&</span> get<span class="br0">(</span><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>U, T<span class="sy1">></span><span class="sy3">&&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(11)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> U<span class="sy1">></span><br />
|
|
<span class="kw4">constexpr</span> <span class="kw4">const</span> T<span class="sy3">&&</span> get<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>U, T<span class="sy1">></span><span class="sy3">&&</span> p<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(12)</td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>用仿 tuple 的接口从 pair 提取元素。</p>
|
|
<p>若序号 <code>I</code> 不是 0 或 1 则基于范围的重载 <span class="t-v">(1-4)</span> 无法编译。</p>
|
|
<p>若类型 <code>T</code> 与 <code>U</code> 相同则基于类型的重载 <span class="t-v">(5-12)</span> 无法编译。</p>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>p</td>
|
|
<td>-</td>
|
|
<td>要提取内容的 pair</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
|
|
<div class="t-li1"><span class="t-li">1-4)</span> 若 <code>I==0</code> 则返回到 <code>p.first</code> 的引用,若 <code>I==1</code> 则返回到 <code>p.second</code> 的引用。</div>
|
|
<div class="t-li1"><span class="t-li">5-8)</span> 返回到 <code>p.first</code> 的引用。</div>
|
|
<div class="t-li1"><span class="t-li">9-12)</span> 返回到 <code>p.second</code> 的引用。</div>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<div class="t-example">
|
|
<div class="t-example-live-link"></div>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="co2">#include <iostream></span>
|
|
<span class="co2">#include <utility></span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw4">auto</span> p <span class="sy1">=</span> <a href="cpp-utility-pair-make_pair.html"><span class="kw1097">std::<span class="me2">make_pair</span></span></a><span class="br0">(</span><span class="nu0">1</span>, <span class="nu16">3.14</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">'('</span> <span class="sy1"><<</span> std<span class="sy4">::</span><span class="me2">get</span><span class="sy1"><</span><span class="nu0">0</span><span class="sy1">></span><span class="br0">(</span>p<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">", "</span> <span class="sy1"><<</span> std<span class="sy4">::</span><span class="me2">get</span><span class="sy1"><</span><span class="nu0">1</span><span class="sy1">></span><span class="br0">(</span>p<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">")<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">'('</span> <span class="sy1"><<</span> std<span class="sy4">::</span><span class="me2">get</span><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span><span class="br0">(</span>p<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">", "</span> <span class="sy1"><<</span> std<span class="sy4">::</span><span class="me2">get</span><span class="sy1"><</span><span class="kw4">double</span><span class="sy1">></span><span class="br0">(</span>p<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">")<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>输出:</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">(1, 3.14)
|
|
(1, 3.14)</pre></div>
|
|
</div>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
|
|
<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
|
|
<table class="dsctable" style="font-size:0.8em">
|
|
<tr>
|
|
<th>DR</th>
|
|
<th>应用于</th>
|
|
<th>出版时的行为</th>
|
|
<th>正确行为</th>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2485">LWG 2485</a></td>
|
|
<td>C++11 (按索引)<br />
|
|
C++14 (按类型)</td>
|
|
<td>无对于 const pair&& 的重载</td>
|
|
<td>添加重载</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td><a href="cpp-language-structured_binding.html">结构化绑定</a> <span class="t-mark-rev t-since-cxx17">(C++17)</span></td>
|
|
<td>绑定指定的名字到初始化器的子对象或元组元素</td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-tuple-get.html"><span class="t-lines"><span>std::get<span class="t-dsc-small">(std::tuple)</span></span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>元组式访问指定的元素<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-container-array-get.html"><span class="t-lines"><span>std::get<span class="t-dsc-small">(std::array)</span></span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>访问 <code>array</code> 的一个元素<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-variant-get.html"><span class="t-lines"><span>std::get<span class="t-dsc-small">(std::variant)</span></span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>以给定索引或类型(若类型唯一)读取 <code>variant</code> 的值,错误时抛出异常<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|