139 lines
10 KiB
HTML
139 lines
10 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::ranges::not_equal_to</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_functional_ranges_not_equal_to 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::ranges::</span>not_equal_to</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-functional.html">functional</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-functional.html"><functional></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">struct</span> not_equal_to<span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>进行比较的函数对象。从实参推导函数调用运算符的形参类型（但非返回类型）。</p>
|
|
<h3><span class="mw-headline" id=".E5.AE.9E.E7.8E.B0.E5.AE.9A.E4.B9.89.E7.9A.84.E6.8C.87.E9.92.88.E4.B8.8A.E7.9A.84.E4.B8.A5.E6.A0.BC.E5.85.A8.E5.BA.8F">实现定义的指针上的严格全序</span></h3>
|
|
<p>若参数间的 <code>=</code> 运算符调用指针的内建比较运算符，则函数调用运算符产生实现定义的指针上的严格全序，即使内建的 <code>=</code> 运算符不如此。</p>
|
|
<p>实现定义的严格全序与比较运算符（ <code><=></code>、 <code><</code>、 <code>></code>、 <code><=</code> 及 <code>>=</code> ）所施加的偏序一致，并在下列标准函数对象间一致：</p>
|
|
<ul>
|
|
<li><span class="t-lc"><a href="cpp-utility-functional-less.html">std::less</a></span>、 <span class="t-lc"><a href="cpp-utility-functional-greater.html">std::greater</a></span>、 <span class="t-lc"><a href="cpp-utility-functional-less_equal.html">std::less_equal</a></span> 及 <span class="t-lc"><a href="cpp-utility-functional-greater_equal.html">std::greater_equal</a></span> ，当模板实参为指针类型或 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span></span></span> 时</li>
|
|
</ul>
|
|
<ul>
|
|
<li><a href="cpp-utility-functional-ranges-equal_to.html"><tt>std::ranges::equal_to</tt></a>、 <strong class="selflink"><tt>std::ranges::not_equal_to</tt></strong>、 <a href="cpp-utility-functional-ranges-less.html"><tt>std::ranges::less</tt></a>、 <a href="cpp-utility-functional-ranges-greater.html"><tt>std::ranges::greater</tt></a>、 <a href="cpp-utility-functional-ranges-less_equal.html"><tt>std::ranges::less_equal</tt></a>、 <a href="cpp-utility-functional-ranges-greater_equal.html"><tt>std::ranges::greater_equal</tt></a> 及 <span class="t-lc">std::compare_three_way</span></li>
|
|
</ul>
|
|
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">成员类型</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc-hitem">
|
|
<td>成员类型</td>
|
|
<td>定义</td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>is_transparent</code></td>
|
|
<td>/* 未指定 */</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">成员函数</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><span class="t-lines"><span>operator()</span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>检查参数是否<i>不相等</i><br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
<div class="t-member">
|
|
<h2><span class="mw-headline" id="std::ranges::not_equal_to::operator.28.29"><span style="font-size:0.7em; line-height:130%">std::ranges::not_equal_to::</span>operator()</span></h2>
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dcl">
|
|
<td class="t-dcl-nopad">
|
|
<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> requires std<span class="sy4">::</span><span class="me2">equality_comparable_with</span><span class="sy1"><</span>T, U<span class="sy1">></span> <span class="co1">// 有不同的语义要求</span><br /></p>
|
|
<span class="kw4">constexpr</span> <span class="kw4">bool</span> operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>T<span class="sy3">&&</span> t, U<span class="sy3">&&</span> u<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td class="t-dcl-nopad"></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>比较 <code>t</code> 与 <code>u</code> 。等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> <span class="sy3">!</span>ranges<span class="sy4">::</span><span class="me2">equal_to</span><span class="br0">{</span><span class="br0">}</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></span></span> 。</p>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">注解</span></h3>
|
|
<p>不同于 <span class="t-lc"><a href="cpp-utility-functional-not_equal_to.html">std::not_equal_to</a></span> ， <code>std::ranges::not_equal_to</code> 要求 <code>==</code> 与 <code>!=</code> 均合法（经由 <a href="cpp-concepts-equality_comparable.html"><code>equality_comparable_with</code></a> 约束），并且完全以 <span class="t-lc">std::ranges::equal_to</span> 定义。然而，实现有直接使用 <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy3">!</span><span class="sy1">=</span></span></span> 的自由，因为那些概念要求 <code>==</code> 与 <code>!=</code> 的结果一致。</p>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<table class="metadata plainlinks ambox mbox-small-left ambox-notice" style="">
|
|
<tr>
|
|
<td class="mbox-empty-cell"></td>
|
|
<td class="mbox-text" style="">本节未完成<br />
|
|
原因：暂无示例</td>
|
|
</tr>
|
|
</table>
|
|
<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/issue3530">LWG 3530</a></td>
|
|
<td>C++20</td>
|
|
<td>在比较指针时放松了语法检查</td>
|
|
<td>仅放松语义要求</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>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-not_equal_to.html"><span class="t-lines"><span>not_equal_to</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>实现 <span class="t-c"><span class="mw-geshi cpp source-cpp">x <span class="sy3">!</span><span class="sy1">=</span> y</span></span> 的函数对象<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|