77 lines
9.5 KiB
HTML
77 lines
9.5 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::experimental::ranges::Swappable, std::experimental::ranges::SwappableWith</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_experimental_ranges_concepts_Swappable 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::experimental::ranges::</span>Swappable, <span style="font-size:0.7em; line-height:130%">std::experimental::ranges::</span>SwappableWith</h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-experimental.html">experimental</a>‎ | <a href="cpp-experimental-ranges.html">ranges</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-experimental-ranges-concepts.html"><experimental/ranges/concepts></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-ranges">
|
|
<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="sy1">></span><br /></span>
|
|
<p>concept <span class="kw4">bool</span> Swappable <span class="sy1">=</span><br />
|
|
requires<span class="br0">(</span>T<span class="sy3">&</span> a, T<span class="sy3">&</span> b<span class="br0">)</span> <span class="br0">{</span><br />
|
|
ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span>a, b<span class="br0">)</span><span class="sy4">;</span><br /></p>
|
|
<span class="br0">}</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(1)</td>
|
|
<td><span class="t-mark-rev t-since-ranges-ts t-mark-ts">(范围 TS)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-ranges">
|
|
<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>
|
|
<p>concept <span class="kw4">bool</span> SwappableWith <span class="sy1">=</span><br />
|
|
<a href="cpp-experimental-ranges-concepts-CommonReference.html"><span class="kw2533">ranges::<span class="me2">CommonReference</span></span></a><span class="sy1"><</span><br />
|
|
<span class="kw4">const</span> <a href="cpp-types-remove_reference.html"><span class="kw607">std::<span class="me2">remove_reference_t</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy3">&</span>,<br />
|
|
<span class="kw4">const</span> <a href="cpp-types-remove_reference.html"><span class="kw607">std::<span class="me2">remove_reference_t</span></span></a><span class="sy1"><</span>U<span class="sy1">></span><span class="sy3">&</span><span class="sy1">></span> <span class="sy3">&&</span><br />
|
|
requires<span class="br0">(</span>T<span class="sy3">&&</span> t, U<span class="sy3">&&</span> u<span class="br0">)</span> <span class="br0">{</span><br />
|
|
ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span><a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="br0">(</span>t<span class="br0">)</span>, <a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="br0">(</span>t<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span><br />
|
|
ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span><a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>U<span class="sy1">></span><span class="br0">(</span>u<span class="br0">)</span>, <a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>U<span class="sy1">></span><span class="br0">(</span>u<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span><br />
|
|
ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span><a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="br0">(</span>t<span class="br0">)</span>, <a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>U<span class="sy1">></span><span class="br0">(</span>u<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span><br />
|
|
ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span><a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>U<span class="sy1">></span><span class="br0">(</span>u<span class="br0">)</span>, <a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="br0">(</span>t<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span><br /></p>
|
|
<span class="br0">}</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(2)</td>
|
|
<td><span class="t-mark-rev t-since-ranges-ts t-mark-ts">(范围 TS)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>概念 <code>Swappable<T></code> 指定 <code>T</code> 类型左值可交换。</p>
|
|
<p>概念 <code>SwappableWith<T, U></code> 指定属于 <code>T</code> 和 <code>U</code> 所编码的类型和值类别的表达式彼此可交换。 <code>SwappableWith<T, U></code> 仅若调用 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span>t, u<span class="br0">)</span></span></span> 交换 <code>t</code> 与 <code>u</code> 的值，即给定等于 <code>t</code> 的独立对象 <code>t2</code> 和等于 <code>u</code> 的独立对象 <code>u2</code> ，求值 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span>t, u<span class="br0">)</span></span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">swap</span><span class="br0">(</span>u, t<span class="br0">)</span></span></span> 后 <code>t2</code> 等于 <code>u</code> 且 <code>u2</code> 等于 <code>t</code> ，才得到满足。</p>
|
|
<h3><span class="mw-headline" id=".E7.9B.B8.E7.AD.89.E6.80.A7.E4.BF.9D.E6.8C.81">相等性保持</span></h3>
|
|
<p>若表达式对给定的相等输入产生相等输出，则它<i>保持相等性</i>。</p>
|
|
<ul>
|
|
<li>表达式的输入由其运算数组成。</li>
|
|
<li>表达式的输出由其结果和表达式所修改的所有运算数（若存在）组成。</li>
|
|
</ul>
|
|
<p>进一步要求每个要求保持相等性的表达式都<i>稳定</i>：这种表达式带相同输入对象的二次求值必须拥有相等的输出，而无任何对这些输入对象的显式中间修改。</p>
|
|
<p>除非另外提醒，每个用于 <i>requires 表达式</i>中的表达式都要求保持相等性且稳定，而表达式的求值必须只修改其非常运算数。必须不修改常运算数。</p>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|