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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::ranges::</span><span style="font-size:0.7em; line-height:130%">views::</span>common, <span style="font-size:0.7em; line-height:130%">std::ranges::</span>common_view</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-ranges.html">ranges</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-ranges.html">&lt;ranges&gt;</a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> ranges<span class="sy4">::</span><span class="me2">view</span> V <span class="sy1">&gt;</span><br /></span>
<p>&nbsp; &nbsp; requires <span class="br0">(</span><span class="sy3">!</span>ranges<span class="sy4">::</span><span class="me2">common_range</span><span class="sy1">&lt;</span>V<span class="sy1">&gt;</span> <span class="sy3">&amp;&amp;</span> std<span class="sy4">::</span><span class="me2">copyable</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>V<span class="sy1">&gt;&gt;</span><span class="br0">)</span><br /></p>
<span class="kw1">class</span> common_view <span class="sy4">:</span> <span class="kw1">public</span> ranges<span class="sy4">::</span><span class="me2">view_interface</span><span class="sy1">&lt;</span>common_view<span class="sy1">&lt;</span>V<span class="sy1">&gt;&gt;</span></div>
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<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">namespace</span> views <span class="br0">{</span><br /></span>
<p>&nbsp; &nbsp; <span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="coMULTI">/*unspecified*/</span> common <span class="sy1">=</span> <span class="coMULTI">/*unspecified*/</span><span class="sy4">;</span><br /></p>
<span class="br0">}</span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<div class="t-li1"><span class="t-li">1)</span> &#23558;&#32473;&#23450;&#30340;&#25317;&#26377;&#30456;&#24322;&#36845;&#20195;&#22120;/&#21736;&#20301;&#31867;&#22411;&#30340; <a href="cpp-ranges-view.html"><code>view</code></a> &#36866;&#37197;&#25104;&#20134;&#20026; <a href="cpp-ranges-common_range.html"><code>common_range</code></a> &#30340; <a href="cpp-ranges-view.html"><code>view</code></a> &#12290; <code>common_view</code> &#22987;&#32456;&#25317;&#26377;&#30456;&#21516;&#30340;&#36845;&#20195;&#22120;/&#21736;&#20301;&#31867;&#22411;&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> <a href="cpp-ranges.html#.E8.8C.83.E5.9B.B4.E9.80.82.E9.85.8D.E5.99.A8.E5.AF.B9.E8.B1.A1">&#33539;&#22260;&#36866;&#37197;&#22120;&#23545;&#35937;</a>&#12290;&#20196; <span class="t-c"><span class="mw-geshi cpp source-cpp">e</span></span> &#20026;&#23376;&#34920;&#36798;&#24335;&#12290;&#21017;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp">views&#8203;<span class="sy4">::</span>&#8203;common<span class="br0">(</span>e<span class="br0">)</span></span></span> <i>&#34920;&#36798;&#24335;&#31561;&#20215;</i>&#20110;&#65306;
<ul>
<li><span class="t-c"><span class="mw-geshi cpp source-cpp">views&#8203;<span class="sy4">::</span>&#8203;all<span class="br0">(</span>e<span class="br0">)</span></span></span> &#65292;&#33509;&#23427;&#20026;<i>&#33391;&#26500;</i>&#34920;&#36798;&#24335;&#19988; <span class="t-c"><span class="mw-geshi cpp source-cpp">decltype<span class="br0">(</span><span class="br0">(</span>e<span class="br0">)</span><span class="br0">)</span></span></span> &#23454;&#29616; <a href="cpp-ranges-common_range.html"><code>common_range</code></a> &#65307;</li>
<li>&#21542;&#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp">common_view<span class="br0">{</span>e<span class="br0">}</span></span></span> &#12290;</li>
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<h3><span class="mw-headline" id=".E8.A1.A8.E8.BE.BE.E5.BC.8F.E7.AD.89.E4.BB.B7">&#34920;&#36798;&#24335;&#31561;&#20215;</span></h3>
<p>&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp">e</span></span> <i>&#34920;&#36798;&#24335;&#31561;&#20215;</i>&#20110;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp">f</span></span> &#65292;&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">e</span></span> &#19982; <span class="t-c"><span class="mw-geshi cpp source-cpp">f</span></span> &#25317;&#26377;&#30456;&#21516;&#25928;&#26524;&#65292;&#22343;&#20026;<a href="cpp-language-noexcept_spec.html">&#28508;&#22312;&#25243;&#20986;</a>&#25110;&#22343;&#38750;&#28508;&#22312;&#25243;&#20986;&#65288;&#21363; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">noexcept</span><span class="br0">(</span>e<span class="br0">)</span> <span class="sy1">==</span> <span class="kw1">noexcept</span><span class="br0">(</span>f<span class="br0">)</span></span></span> &#65289;&#65292;&#19988;&#22343;&#20026;<a href="cpp-language-constant_expression.html">&#24120;&#37327;&#23376;&#34920;&#36798;&#24335;</a>&#25110;&#22343;&#38750;&#24120;&#37327;&#23376;&#34920;&#36798;&#24335;&#12290;</p>
<h3><span class="mw-headline" id=".E6.95.B0.E6.8D.AE.E6.88.90.E5.91.98">&#25968;&#25454;&#25104;&#21592;</span></h3>
<p><code>common_view</code> &#30340;&#20856;&#22411;&#23454;&#29616;&#20165;&#20445;&#26377;&#19968;&#20010;&#38750;&#38745;&#24577;&#25968;&#25454;&#25104;&#21592;&#65306; <code>V</code> &#31867;&#22411;&#30340;&#24213;&#23618;&#35270;&#22270;&#12290;</p>
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">&#25104;&#21592;&#20989;&#25968;</span></h3>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
<div><a href="cpp-ranges-common_view-common_view.html"><span class="t-lines"><span>(&#26500;&#36896;&#20989;&#25968;)</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
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<td>&#26500;&#36896; <code>common_view</code><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-common_view-base.html"><span class="t-lines"><span>base</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#24213;&#23618;&#65288;&#36866;&#37197;&#30340;&#65289;&#35270;&#22270;&#30340;&#21103;&#26412;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-common_view-begin.html"><span class="t-lines"><span>begin</span></span></a></div>
<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>&#36820;&#22238;&#25351;&#21521;&#36215;&#22987;&#30340;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-common_view-end.html"><span class="t-lines"><span>end</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
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<td>&#36820;&#22238;&#25351;&#21521;&#26411;&#23614;&#30340;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-common_view-size.html"><span class="t-lines"><span>size</span></span></a></div>
<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>&#36820;&#22238;&#20803;&#32032;&#25968;&#65292;&#21482;&#35201;&#24213;&#23618;&#65288;&#36866;&#37197;&#30340;&#65289;&#33539;&#22260;&#28385;&#36275; <a href="cpp-ranges-sized_range.html"><code>sized_range</code></a><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<td colspan="2">
<h5><span class="mw-headline" id=".E7.BB.A7.E6.89.BF.E8.87.AA_std::ranges::view_interface">&#32487;&#25215;&#33258; <span class="t-lc">std::ranges::view_interface</span></span></h5>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-empty.html"><span class="t-lines"><span>empty</span></span></a></div>
<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>&#36820;&#22238;&#35270;&#22270;&#26159;&#21542;&#20026;&#31354;&#12290;&#33509;&#35270;&#22270;&#28385;&#36275; <a href="cpp-ranges-forward_range.html"><code>forward_range</code></a> &#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-operator_bool.html"><span class="t-lines"><span>operator bool</span></span></a></div>
<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>&#36820;&#22238;&#27966;&#29983;&#35270;&#22270;&#26159;&#21542;&#20026;&#38750;&#31354;&#12290;&#33509; <span class="t-lc">ranges::empty</span> &#21487;&#24212;&#29992;&#20110;&#23427;&#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-data.html"><span class="t-lines"><span>data</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#27966;&#29983;&#35270;&#22270;&#30340;&#25968;&#25454;&#30340;&#22320;&#22336;&#12290;&#33509;&#35270;&#22270;&#30340;&#36845;&#20195;&#22120;&#31867;&#22411;&#28385;&#36275; <a href="cpp-iterator-contiguous_iterator.html"><code>contiguous_iterator</code></a> &#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-front.html"><span class="t-lines"><span>front</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
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<td>&#36820;&#22238;&#27966;&#29983;&#35270;&#22270;&#20013;&#30340;&#39318;&#20803;&#32032;&#12290;&#33509;&#35270;&#22270;&#28385;&#36275; <a href="cpp-ranges-forward_range.html"><code>forward_range</code></a> &#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-back.html"><span class="t-lines"><span>back</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
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<td>&#36820;&#22238;&#27966;&#29983;&#35270;&#22270;&#20013;&#30340;&#26411;&#20803;&#32032;&#12290;&#33509;&#35270;&#22270;&#28385;&#36275; <a href="cpp-ranges-bidirectional_range.html"><code>bidirectional_range</code></a> &#19982; <a href="cpp-ranges-common_range.html"><code>common_range</code></a> &#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-ranges-view_interface-operator_at.html"><span class="t-lines"><span>operator[]</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
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<td>&#36820;&#22238;&#27966;&#29983;&#35270;&#22270;&#20013;&#30340;&#31532; n &#20010;&#20803;&#32032;&#12290;&#33509;&#35270;&#22270;&#28385;&#36275; <a href="cpp-ranges-random_access_range.html"><code>random_access_range</code></a> &#21017;&#25552;&#20379;&#12290;<br />
<span class="t-mark">(<code>std::ranges::view_interface&lt;D&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h3><span class="mw-headline" id=".E6.8E.A8.E5.AF.BC.E6.8C.87.E5.BC.95"><a href="cpp-ranges-common_view-deduction_guides.html">&#25512;&#23548;&#25351;&#24341;</a></span></h3>
<h3><span class="mw-headline" id=".E8.BE.85.E5.8A.A9.E6.A8.A1.E6.9D.BF">&#36741;&#21161;&#27169;&#26495;</span></h3>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> T<span class="sy1">&gt;</span><br /></span>
<p><span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> enable_borrowed_range<span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">common_view</span><span class="sy1">&lt;</span>T<span class="sy1">&gt;&gt;</span> <span class="sy1">=</span><br /></p>
&nbsp; &nbsp; std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">enable_borrowed_range</span><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy4">;</span></div>
</td>
<td class="t-dcl-nopad"></td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<p><a href="cpp-ranges-borrowed_range.html"><tt>std::ranges::enable_borrowed_range</tt></a> &#30340;&#27492;&#29305;&#21270;&#20351;&#24471; <code>common_view</code> &#22312;&#24213;&#23618;&#31867;&#22411;&#23454;&#29616; <a href="cpp-ranges-borrowed_range.html"><code>borrowed_range</code></a> &#26102;&#23454;&#29616;&#23427;&#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p><code>common_view</code> &#23545;&#20110;&#20351;&#29992;&#26399;&#24453;&#36845;&#20195;&#22120;&#19982;&#21736;&#20301;&#20026;&#30456;&#21516;&#31867;&#22411;&#30340;&#20256;&#32479;&#31639;&#27861;&#26377;&#29992;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</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 &lt;iostream&gt;</span>
<span class="co2">#include &lt;iterator&gt;</span>
<span class="co2">#include &lt;numeric&gt;</span>
<span class="co2">#include &lt;ranges&gt;</span>
<span class="co2">#include &lt;list&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw4">auto</span> v1 <span class="sy1">=</span> <span class="br0">{</span> <span class="nu0">1</span>, <span class="nu0">2</span>, <span class="nu0">3</span>, <span class="nu0">4</span>, <span class="nu0">5</span> <span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> i1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">counted_iterator</span><span class="br0">{</span>v1.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, std<span class="sy4">::</span><span class="me2">ssize</span><span class="br0">(</span>v1<span class="br0">)</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> r1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">subrange</span><span class="br0">{</span>i1, std<span class="sy4">::</span><span class="me2">default_sentinel</span><span class="br0">}</span><span class="sy4">;</span>
<span class="co1">// auto e1 = std::accumulate(r1.begin(), r1.end(), 0); // &#38169;&#35823;&#65306;&#35201;&#27714;&ldquo;&#20849;&#21516;&#33539;&#22260;&rdquo;</span>
<span class="kw4">auto</span> c1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">common_view</span><span class="br0">{</span>r1<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">&lt;&lt;</span> <span class="st0">&quot;accumulate: &quot;</span> <span class="sy1">&lt;&lt;</span> <a href="cpp-algorithm-accumulate.html"><span class="kw1651">std::<span class="me2">accumulate</span></span></a><span class="br0">(</span>c1.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, c1.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, <span class="nu0">0</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="co1">// &#20174; ranges::view_interface &#32487;&#25215;&#65306;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;c1.front(): &quot;</span> <span class="sy1">&lt;&lt;</span> c1.<span class="me1">front</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</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">&lt;&lt;</span> <span class="st0">&quot;c1.back(): &quot;</span> <span class="sy1">&lt;&lt;</span> c1.<span class="me1">back</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</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">&lt;&lt;</span> <span class="st0">&quot;c1.data(): &quot;</span> <span class="sy1">&lt;&lt;</span> c1.<span class="me1">data</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</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">&lt;&lt;</span> <span class="st0">&quot;c1[0]: &quot;</span> <span class="sy1">&lt;&lt;</span> c1<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="kw4">auto</span> v2 <span class="sy1">=</span> <a href="cpp-container-list.html"><span class="kw1275">std::<span class="me2">list</span></span></a><span class="br0">{</span> <span class="nu0">1</span>, <span class="nu0">2</span>, <span class="nu0">3</span>, <span class="nu0">4</span>, <span class="nu0">5</span> <span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> i2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">counted_iterator</span><span class="br0">{</span>v2.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, std<span class="sy4">::</span><span class="me2">ssize</span><span class="br0">(</span>v2<span class="br0">)</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> r2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">subrange</span><span class="br0">{</span>i2, std<span class="sy4">::</span><span class="me2">default_sentinel</span><span class="br0">}</span><span class="sy4">;</span>
<span class="co1">// auto e2 = std::accumulate(r2.begin(), r2.end(), 0); // &#38169;&#35823;&#65306;&#35201;&#27714;&ldquo;&#20849;&#21516;&#33539;&#22260;&rdquo;</span>
<span class="kw4">auto</span> c2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">common_view</span><span class="br0">{</span>r2<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">&lt;&lt;</span> <span class="st0">&quot;accumulate: &quot;</span> <span class="sy1">&lt;&lt;</span> <a href="cpp-algorithm-accumulate.html"><span class="kw1651">std::<span class="me2">accumulate</span></span></a><span class="br0">(</span>c2.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, c2.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, <span class="nu0">0</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="co1">// inherited from ranges::view_interface:</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;c2.front(): &quot;</span> <span class="sy1">&lt;&lt;</span> c2.<span class="me1">front</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="co1">// auto e3 = c2.back(); // &#38169;&#35823;&#65306;&#35201;&#27714;&ldquo;&#36830;&#32493;&#33539;&#22260;&rdquo;</span>
<span class="co1">// auto e4 = c2.data(); // &#38169;&#35823;&#65306;&#35201;&#27714;&ldquo;&#36830;&#32493;&#33539;&#22260;&rdquo;</span>
<span class="co1">// auto e5 = c2[0]; // &#38169;&#35823;&#65306;&#35201;&#27714;&ldquo;&#36830;&#32493;&#33539;&#22260;&rdquo;</span>
<span class="br0">}</span></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<div class="text source-text">
<pre class="de1">accumulate: 15
c1.front(): 1
c1.back(): 5
c1.data(): 0x400ec0
c1[0]: 1
accumulate: 15
c2.front(): 1</pre></div>
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<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">&#32570;&#38519;&#25253;&#21578;</span></h3>
<p>&#19979;&#21015;&#26356;&#25913;&#34892;&#20026;&#30340;&#32570;&#38519;&#25253;&#21578;&#36861;&#28335;&#22320;&#24212;&#29992;&#20110;&#20197;&#21069;&#20986;&#29256;&#30340; C++ &#26631;&#20934;&#12290;</p>
<table class="dsctable" style="font-size:0.8em">
<tr>
<th>DR</th>
<th>&#24212;&#29992;&#20110;</th>
<th>&#20986;&#29256;&#26102;&#30340;&#34892;&#20026;</th>
<th>&#27491;&#30830;&#34892;&#20026;</th>
</tr>
<tr>
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue3494">LWG 3494</a></td>
<td>C++20</td>
<td><code>common_view</code> &#22987;&#32456;&#19981;&#26159; <code>borrowed_range</code></td>
<td>&#33509;&#24213;&#23618;&#35270;&#22270;&#26159; <code>borrowed_range</code> &#21017;&#23427;&#26159;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-ranges-common_range.html"><span class="t-lines"><span>ranges::common_range</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#25351;&#23450;&#33539;&#22260;&#25317;&#26377;&#30456;&#21516;&#30340;&#36845;&#20195;&#22120;&#21644;&#21736;&#20301;&#31867;&#22411;<br />
<span class="t-mark">(&#27010;&#24565;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-common_iterator.html"><span class="t-lines"><span>common_iterator</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#36866;&#37197;&#19968;&#20010;&#36845;&#20195;&#22120;&#31867;&#22411;&#21450;&#20854;&#21736;&#20301;&#20026;&#19968;&#20010;&#20844;&#20849;&#36845;&#20195;&#22120;&#31867;&#22411;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
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