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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::ranges::drop_view&lt;V&gt;::</span>drop_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>&lrm; | <a href="cpp-ranges-drop_view.html">drop view</a></span></div>
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<div><span class="mw-geshi cpp source-cpp">drop_view<span class="br0">(</span><span class="br0">)</span> requires std<span class="sy4">::</span><span class="me2">default_initializable</span><span class="sy1">&lt;</span>V<span class="sy1">&gt;</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span></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="kw4">constexpr</span> drop_view<span class="br0">(</span> V base, ranges<span class="sy4">::</span><span class="me2">range_difference_t</span><span class="sy1">&lt;</span>V<span class="sy1">&gt;</span> count <span class="br0">)</span><span class="sy4">;</span></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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<p>&#26500;&#36896; <code>drop_view</code> &#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#40664;&#35748;&#26500;&#36896;&#20989;&#25968;&#12290;<a href="cpp-language-value_initialization.html">&#20540;&#21021;&#22987;&#21270;</a>&#24213;&#23618;&#35270;&#22270;&#24182;&#21021;&#22987;&#21270;&#35745;&#25968;&#20026; 0 &#12290;&#26500;&#36896;&#21518; <a href="cpp-ranges-drop_view-base.html"><code>base()</code></a> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp">V<span class="br0">(</span><span class="br0">)</span></span></span> &#30340;&#21103;&#26412;&#32780; <a href="cpp-ranges-drop_view-size.html"><code>size()</code></a> &#31561;&#20110;&#24213;&#23618;&#35270;&#22270;&#30340;&#22823;&#23567;&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>base<span class="br0">)</span></span></span> &#21021;&#22987;&#21270;&#24213;&#23618;&#35270;&#22270;&#24182;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">count</span></span> &#21021;&#22987;&#21270;&#35745;&#25968;&#12290;&#26500;&#36896;&#21518; <a href="cpp-ranges-drop_view-base.html"><code>base()</code></a> &#36820;&#22238; <code>base</code> &#30340;&#21103;&#26412;&#32780; <a href="cpp-ranges-drop_view-size.html"><code>size()</code></a> &#33509; <code>base</code> &#30340;&#22823;&#23567;&#19981;&#23567;&#20110; <code>count</code> &#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">size</span><span class="br0">(</span>base<span class="br0">)</span> <span class="sy2">-</span> count</span></span> &#65292;&#21542;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp">&#8203;<span class="nu0">0</span>&#8203;</span></span> &#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>base</td>
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<td>&#24213;&#23618;&#35270;&#22270;</td>
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<td>&#35201;&#36339;&#36807;&#30340;&#20803;&#32032;&#25968;</td>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;algorithm&gt;</span>
<span class="co2">#include &lt;array&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;iterator&gt;</span>
<span class="co2">#include &lt;ranges&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">constexpr</span> <a href="cpp-container-array.html"><span class="kw1268">std::<span class="me2">array</span></span></a> hi<span class="br0">{</span> <span class="st0">&#39;H&#39;</span>,<span class="st0">&#39;e&#39;</span>,<span class="st0">&#39;l&#39;</span>,<span class="st0">&#39;l&#39;</span>,<span class="st0">&#39;o&#39;</span>,<span class="st0">&#39;,&#39;</span>,<span class="st0">&#39; &#39;</span>,<span class="st0">&#39;C&#39;</span>,<span class="st0">&#39;+&#39;</span>,<span class="st0">&#39;+&#39;</span>,<span class="st0">&#39;2&#39;</span>,<span class="st0">&#39;0&#39;</span> <span class="br0">}</span><span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">for_each</span><span class="br0">(</span>hi, <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span> c<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">&lt;&lt;</span> c<span class="sy4">;</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">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">auto</span> n <span class="sy1">=</span> <a href="cpp-iterator-distance.html"><span class="kw673">std::<span class="me2">distance</span></span></a><span class="br0">(</span>hi.<span class="me1">cbegin</span><span class="br0">(</span><span class="br0">)</span>, std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">find</span><span class="br0">(</span>hi, <span class="st0">&#39;C&#39;</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">auto</span> cxx <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">drop_view</span><span class="br0">{</span> hi, n <span class="br0">}</span><span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">for_each</span><span class="br0">(</span>cxx, <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span> c<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">&lt;&lt;</span> c<span class="sy4">;</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">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">Hello, C++20
C++20</pre></div>
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