302 lines
30 KiB
HTML
302 lines
30 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>operator==,!=,<,<=,>,>=,<=>(std::unique_ptr)</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_memory_unique_ptr_operator_cmp skin-cppreference2 action-view cpp-navbar">
|
|
<div id="cpp-content-base">
|
|
<div id="content"><a id="top"></a>
|
|
<h1 id="firstHeading" class="firstHeading">operator==,!=,<,<=,>,>=,<=><small>(std::unique_ptr)</small></h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-memory.html">memory</a>‎ | <a href="cpp-memory-unique_ptr.html">unique ptr</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-memory.html"><memory></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">==</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(1)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy3">!</span><span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(2)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(3)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(4)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">></span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(5)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">>=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(6)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T1, <span class="kw1">class</span> D1, <span class="kw1">class</span> T2, <span class="kw1">class</span> D2<span class="sy1">></span><br /></span>
|
|
<p> requires std<span class="sy4">::</span><span class="me2">three_way_comparable_with</span><span class="sy1"><</span><br />
|
|
<span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span>,<br />
|
|
<span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><br />
|
|
std<span class="sy4">::</span><span class="me2">compare_three_way_result_t</span><span class="sy1"><</span><span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span>,<br />
|
|
<span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><br /></p>
|
|
operator<span class="sy1"><=></span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy3">&</span> x, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(7)</td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">==</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><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-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">==</span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x<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-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy3">!</span><span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><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-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11 t-until-cxx20">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy3">!</span><span class="sy1">=</span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x<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-cxx11">(C++11 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(12)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><</span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(13)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(14)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1"><=</span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(15)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">></span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(16)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">></span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(17)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">>=</span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(18)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx11">
|
|
<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> D<span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> operator<span class="sy1">>=</span><span class="br0">(</span><a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a>, <span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> y<span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td>(19)</td>
|
|
<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<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> D<span class="sy1">></span><br /></span>
|
|
<p> requires std<span class="sy4">::</span><span class="me2">three_way_comparable</span><span class="sy1"><</span><span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><br />
|
|
std<span class="sy4">::</span><span class="me2">compare_three_way_result_t</span><span class="sy1"><</span><span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><br /></p>
|
|
operator<span class="sy1"><=></span><span class="br0">(</span><span class="kw4">const</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy3">&</span> x, <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a><span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(20)</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>比较二个 <code>unique_ptr</code> 或 <code>unique_ptr</code> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr</span></span> 的指针值。</p>
|
|
<div class="t-li1"><span class="t-li">1-7)</span> 比较二个 <code>unique_ptr</code> 。</div>
|
|
<div class="t-li1"><span class="t-li">8-20)</span> 比较 <code>unique_ptr</code> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr</span></span> 。</div>
|
|
<table class="t-rev-begin">
|
|
<tr class="t-rev t-since-cxx20">
|
|
<td>
|
|
<p><code>!=</code> 运算符从 <code>operator==</code> <a href="cpp-language-operators.html#.E5.85.B3.E7.B3.BB.E8.BF.90.E7.AE.97.E7.AC.A6">合成</a>。</p>
|
|
</td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</table>
|
|
<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>x, y</td>
|
|
<td>-</td>
|
|
<td>要比较的 <code>unique_ptr</code></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)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> y.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">2)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> y.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">3)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-functional-less.html"><span class="kw1039">std::<span class="me2">less</span></span></a><span class="sy1"><</span>CT<span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>, y.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> ,其中 <code>CT</code> 是 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-common_type.html"><span class="kw635">std::<span class="me2">common_type</span></span></a><span class="sy1"><</span>unique_ptr<span class="sy1"><</span>T1, D1<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span>, unique_ptr<span class="sy1"><</span>T2, D2<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">4)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>y <span class="sy1"><</span> x<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">5)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">y <span class="sy1"><</span> x</span></span></div>
|
|
<div class="t-li1"><span class="t-li">6)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>x <span class="sy1"><</span> y<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">7)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">compare_three_way</span><span class="br0">{</span><span class="br0">}</span><span class="br0">(</span>x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>, y.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">8-9)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span>x</span></span></div>
|
|
<div class="t-li1"><span class="t-li">10-11)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">(</span><span class="kw4">bool</span><span class="br0">)</span>x</span></span></div>
|
|
<div class="t-li1"><span class="t-li">12)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-functional-less.html"><span class="kw1039">std::<span class="me2">less</span></span></a><span class="sy1"><</span>unique_ptr<span class="sy1"><</span>T,D<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>, nullptr<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">13)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-functional-less.html"><span class="kw1039">std::<span class="me2">less</span></span></a><span class="sy1"><</span>unique_ptr<span class="sy1"><</span>T,D<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>nullptr, y.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">14)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>nullptr <span class="sy1"><</span> x<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">15)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>y <span class="sy1"><</span> nullptr<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">16)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr <span class="sy1"><</span> x</span></span></div>
|
|
<div class="t-li1"><span class="t-li">17)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">y <span class="sy1"><</span> nullptr</span></span></div>
|
|
<div class="t-li1"><span class="t-li">18)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>x <span class="sy1"><</span> nullptr<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">19)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>nullptr <span class="sy1"><</span> y<span class="br0">)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">20)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">compare_three_way</span><span class="br0">{</span><span class="br0">}</span><span class="br0">(</span>x.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>, <span class="kw1">static_cast</span><span class="sy1"><</span><span class="kw1">typename</span> unique_ptr<span class="sy1"><</span>T, D<span class="sy1">></span><span class="sy4">::</span><span class="me2">pointer</span><span class="sy1">></span><span class="br0">(</span>nullptr<span class="br0">)</span><span class="br0">)</span></span></span></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 <memory></span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span> p1<span class="br0">(</span>new <span class="kw4">int</span><span class="br0">(</span><span class="nu0">42</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span> p2<span class="br0">(</span>new <span class="kw4">int</span><span class="br0">(</span><span class="nu0">42</span><span class="br0">)</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">"p1 == p1: "</span> <span class="sy1"><<</span> <span class="br0">(</span>p1 <span class="sy1">==</span> p1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// p1 与 p2 指向不同内存位置,故 p1 != p2</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">"p1 == p2: "</span> <span class="sy1"><<</span> <span class="br0">(</span>p1 <span class="sy1">==</span> p2<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">p1 == p1: 1
|
|
p1 == p2: 0</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/issue3426">LWG 3426</a></td>
|
|
<td>C++20</td>
|
|
<td><code>operator<=>(unique_ptr, nullptr_t)</code> 为谬构</td>
|
|
<td>修正约束与定义</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-memory-unique_ptr-get.html"><span class="t-lines"><span>get</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>返回指向被管理对象的指针<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|