450 lines
29 KiB
HTML
450 lines
29 KiB
HTML
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<title>std::ranges::ref_view</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_ranges_ref_view skin-cppreference2 action-view cpp-navbar">
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::ranges::</span>ref_view</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-ranges.html">ranges</a></span></div>
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<div>定义于头文件 <code><a href="cpp-header-ranges.html"><ranges></a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span>ranges<span class="sy4">::</span><span class="me2">range</span> R<span class="sy1">></span><br /></span>
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<p> requires <a href="cpp-types-is_object.html"><span class="kw487">std::<span class="me2">is_object_v</span></span></a><span class="sy1"><</span>R<span class="sy1">></span><br /></p>
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<span class="kw1">class</span> ref_view <span class="sy4">:</span> <span class="kw1">public</span> ranges<span class="sy4">::</span><span class="me2">view_interface</span><span class="sy1"><</span>ref_view<span class="sy1"><</span>R<span class="sy1">>></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<p><code>ref_view</code> 是某个其他 <a href="cpp-ranges-range.html"><code>range</code></a> 的元素的 <a href="cpp-ranges-view.html"><code>view</code></a> 。它包装到该 <code>range</code> 的引用。</p>
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<h3><span class="mw-headline" id=".E6.95.B0.E6.8D.AE.E6.88.90.E5.91.98">数据成员</span></h3>
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<p><code>ref_view</code> 表现如同它仅存储一个指向被引用范围的 <span class="t-c"><span class="mw-geshi cpp source-cpp">R<span class="sy2">*</span></span></span> 成员子对象。此处显示该成员为 <code><i>r_</i></code> （名称仅用于阐释）。</p>
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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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<div class="t-dsc-member-div t-dsc-member-nobold-div">
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<div><span class="t-lines"><span>(构造函数)</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>构造引用给定范围的 <code>ref_view</code><br />
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<span class="t-mark">(公开成员函数)</span></td>
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<tr class="t-dsc">
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<div class="t-dsc-member-div">
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<div><span class="t-lines"><span>base</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>返回到被引用范围的引用<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<td>
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<div class="t-dsc-member-div">
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<div><span class="t-lines"><span>begin</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>返回被引用范围的起始迭代器<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<td>
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<div class="t-dsc-member-div">
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<div><span class="t-lines"><span>end</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>返回被引用范围的哨位<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<div><span class="t-lines"><span>empty</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>检查被引用范围是否为空<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<div class="t-dsc-member-div">
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<div><span class="t-lines"><span>size</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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<td>返回被引用 <a href="cpp-ranges-sized_range.html"><code>sized_range</code></a> 的大小<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<td>
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<div class="t-dsc-member-div">
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<div><span class="t-lines"><span>data</span></span></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</td>
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<td>返回指向被引用 <a href="cpp-ranges-contiguous_range.html"><code>contiguous_range</code></a> 起始的指针<br />
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<span class="t-mark">(公开成员函数)</span></td>
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<h5><span class="mw-headline" id=".E7.BB.A7.E6.89.BF.E8.87.AA_std::ranges::view_interface">继承自 <span class="t-lc">std::ranges::view_interface</span></span></h5>
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<div><a href="cpp-ranges-view_interface-operator_bool.html"><span class="t-lines"><span>operator bool</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>返回派生视图是否为非空。若 <span class="t-lc">ranges::empty</span> 可应用于它则提供。<br />
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<span class="t-mark">(<code>std::ranges::view_interface<D></code> 的公开成员函数)</span></td>
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<div><a href="cpp-ranges-view_interface-front.html"><span class="t-lines"><span>front</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>返回派生视图中的首元素。若视图满足 <a href="cpp-ranges-forward_range.html"><code>forward_range</code></a> 则提供。<br />
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<span class="t-mark">(<code>std::ranges::view_interface<D></code> 的公开成员函数)</span></td>
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<tr class="t-dsc">
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<div><a href="cpp-ranges-view_interface-back.html"><span class="t-lines"><span>back</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>返回派生视图中的末元素。若视图满足 <a href="cpp-ranges-bidirectional_range.html"><code>bidirectional_range</code></a> 与 <a href="cpp-ranges-common_range.html"><code>common_range</code></a> 则提供。<br />
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<span class="t-mark">(<code>std::ranges::view_interface<D></code> 的公开成员函数)</span></td>
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<div><a href="cpp-ranges-view_interface-operator_at.html"><span class="t-lines"><span>operator[]</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>返回派生视图中的第 n 个元素。若视图满足 <a href="cpp-ranges-random_access_range.html"><code>random_access_range</code></a> 则提供。<br />
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<span class="t-mark">(<code>std::ranges::view_interface<D></code> 的公开成员函数)</span></td>
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</tr>
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</table>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::ref_view"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>ref_view</span></h2>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="coMULTI">/*different-from*/</span><span class="sy1"><</span>ref_view<span class="sy1">></span> T<span class="sy1">></span><br /></span>
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<p> requires std<span class="sy4">::</span><span class="me2">convertible_to</span><span class="sy1"><</span>T, R<span class="sy3">&</span><span class="sy1">></span> <span class="sy3">&&</span> requires <span class="br0">{</span> _FUN<span class="br0">(</span><a href="cpp-utility-declval.html"><span class="kw1120">std::<span class="me2">declval</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span><br /></p>
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<span class="kw4">constexpr</span> ref_view<span class="br0">(</span>T<span class="sy3">&&</span> t<span class="br0">)</span><span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<p>以 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-addressof.html"><span class="kw757">std::<span class="me2">addressof</span></span></a><span class="br0">(</span><span class="kw1">static_cast</span><span class="sy1"><</span>R<span class="sy3">&</span><span class="sy1">></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><span class="br0">)</span><span class="br0">)</span></span></span> 初始化 <code><i>r_</i></code> 。</p>
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<p><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="coMULTI">/*different-from*/</span><span class="sy1"><</span>T, U<span class="sy1">></span></span></span> 当且仅当 <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">remove_cvref_t</span><span class="sy1"><</span>T<span class="sy1">></span></span></span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">remove_cvref_t</span><span class="sy1"><</span>U<span class="sy1">>></span></span></span> 不是同一类型才得到满足，而 <code><i>_FUN</i></code> 的重载声明为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> _FUN<span class="br0">(</span>R<span class="sy3">&</span><span class="br0">)</span><span class="sy4">;</span> <span class="kw4">void</span> _FUN<span class="br0">(</span>R<span class="sy3">&&</span><span class="br0">)</span> <span class="sy1">=</span> delete<span class="sy4">;</span></span></span> 。</p>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>t</td>
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<td>-</td>
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<td>要引用的范围</td>
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</div>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::rev_view::base"><span style="font-size:0.7em; line-height:130%">std::ranges::rev_view::</span>base</span></h2>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> R<span class="sy3">&</span> base<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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<p>等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> <span class="sy2">*</span>r_<span class="sy4">;</span></span></span></p>
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</div>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::begin"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>begin</span></h2>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1"><</span>R<span class="sy1">></span> begin<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</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-cxx20">(C++20 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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<p>等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">begin</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span></span></span></p>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::end"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>end</span></h2>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">sentinel_t</span><span class="sy1"><</span>R<span class="sy1">></span> end<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</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-cxx20">(C++20 起)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</table>
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<p>等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span></span></span></p>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::empty"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>empty</span></h2>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">bool</span> empty<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><br />
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requires requires <span class="br0">{</span> ranges<span class="sy4">::</span><span class="me2">empty</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<p>等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">empty</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span></span></span></p>
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</div>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::size"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>size</span></h2>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">auto</span> size<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><br /></span>
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<p> requires ranges<span class="sy4">::</span><span class="me2">sized_range</span><span class="sy1"><</span>R<span class="sy1">></span><br /></p>
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<span class="br0">{</span> <span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">size</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</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-cxx20">(C++20 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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</div>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::ranges::ref_view::data"><span style="font-size:0.7em; line-height:130%">std::ranges::ref_view::</span>data</span></h2>
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<table class="t-dcl-begin">
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">auto</span> data<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><br /></span>
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<p> requires ranges<span class="sy4">::</span><span class="me2">contiguous_range</span><span class="sy1"><</span>R<span class="sy1">></span><br /></p>
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<span class="br0">{</span> <span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">data</span><span class="br0">(</span><span class="sy2">*</span>r_<span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</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-cxx20">(C++20 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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</div>
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<h3><span class="mw-headline" id=".E6.8E.A8.E5.AF.BC.E6.8C.87.E5.BC.95">推导指引</span></h3>
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<table class="t-dcl-begin">
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<tr class="t-dcl t-since-cxx20">
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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="sy1">></span><br />
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ref_view<span class="br0">(</span>R<span class="sy3">&</span><span class="br0">)</span> <span class="sy2">-</span><span class="sy1">></span> ref_view<span class="sy1"><</span>R<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-cxx20">(C++20 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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<h3><span class="mw-headline" id=".E8.BE.85.E5.8A.A9.E6.A8.A1.E6.9D.BF">辅助模板</span></h3>
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<table class="t-dcl-begin">
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<tbody>
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<tr class="t-dcl t-since-cxx20">
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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> T<span class="sy1">></span><br />
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<span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> enable_borrowed_range<span class="sy1"><</span>ranges<span class="sy4">::</span><span class="me2">ref_view</span><span class="sy1"><</span>T<span class="sy1">>></span> <span class="sy1">=</span> <span class="kw2">true</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-cxx20">(C++20 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</table>
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<p><a href="cpp-ranges-borrowed_range.html"><tt>std::ranges::enable_borrowed_range</tt></a> 的此特化使得 <code>ref_view</code> 满足 <a href="cpp-ranges-borrowed_range.html"><code>borrowed_range</code></a> 。</p>
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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 <ranges></span>
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<span class="co2">#include <iostream></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="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s<span class="br0">{</span><span class="st0">"cosmos"</span><span class="br0">}</span><span class="sy4">;</span>
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<span class="kw4">const</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">take_view</span> tv<span class="br0">{</span>s, <span class="nu0">3</span><span class="br0">}</span><span class="sy4">;</span>
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<span class="kw4">const</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">ref_view</span> rv<span class="br0">{</span>tv<span class="br0">}</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a>
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<span class="sy1"><<</span> <a href="cpp-io-manip-boolalpha.html"><span class="kw1764">std::<span class="me2">boolalpha</span></span></a>
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<span class="sy1"><<</span> <span class="st0">"call empty() : "</span> <span class="sy1"><<</span> rv.<span class="me1">empty</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
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<span class="sy1"><<</span> <span class="st0">"call size() : "</span> <span class="sy1"><<</span> rv.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
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<span class="sy1"><<</span> <span class="st0">"call begin() : "</span> <span class="sy1"><<</span> <span class="sy2">*</span>rv.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
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<span class="sy1"><<</span> <span class="st0">"call end() : "</span> <span class="sy1"><<</span> <span class="sy2">*</span><span class="br0">(</span>rv.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="nu0">1</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
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<span class="sy1"><<</span> <span class="st0">"call data() : "</span> <span class="sy1"><<</span> rv.<span class="me1">data</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
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<span class="sy1"><<</span> <span class="st0">"call base() : "</span> <span class="sy1"><<</span> rv.<span class="me1">base</span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span> <span class="co1">// ~> tv.size()</span>
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<span class="sy1"><<</span> <span class="st0">"range-for : "</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">const</span> <span class="kw4">auto</span> c<span class="sy4">:</span> rv<span class="br0">)</span> <span class="br0">{</span> <a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> c<span class="sy4">;</span> <span class="br0">}</span>
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<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 class="es1">\n</span>'</span><span class="sy4">;</span>
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<span class="br0">}</span></pre></div>
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</div>
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<p>输出：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="text source-text">
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<pre class="de1">call empty() : false
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call size() : 3
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call begin() : c
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call end() : s
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call data() : cosmos
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call base() : 3
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range-for : cos</pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
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<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>
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<table class="dsctable" style="font-size:0.8em">
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<tr>
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<th>DR</th>
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<th>应用于</th>
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<th>出版时的行为</th>
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<th>正确行为</th>
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</tr>
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<tr>
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<td><a rel="nofollow" class="external text" href="https://wg21.link/P2325R3">P2325R3</a></td>
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<td>C++20</td>
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<td>由于 <a href="cpp-ranges-view.html"><code>view</code></a> 必须为 <a href="cpp-concepts-default_initializable.html"><code>default_initializable</code></a> 提供了默认构造函数</td>
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<td>与该要求一同移除</td>
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</tr>
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</table>
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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">
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<div><a href="cpp-utility-functional-reference_wrapper.html"><span class="t-lines"><span>reference_wrapper</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><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> 且<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> 的引用包装器<br />
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<span class="t-mark">(类模板)</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-ranges-owning_view.html"><span class="t-lines"><span>ranges::owning_view</span></span></a></div>
|
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>拥有某 <a href="cpp-ranges-range.html"><code>range</code></a> 的独占所有权的 <a href="cpp-ranges-view.html"><code>view</code></a><br />
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<span class="t-mark">(类模板)</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-ranges-all_view.html"><span class="t-lines"><span>views::all_t</span><span>views::all</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>包含 <a href="cpp-ranges-range.html"><code>range</code></a> 的所有元素的 <a href="cpp-ranges-view.html"><code>view</code></a><br />
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<span class="t-mark">(别名模板)</span> <span class="t-mark">(范围适配器对象)</span></td>
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</tr>
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</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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