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<title>std::istream_iterator&lt;T,CharT,Traits,Distance&gt;::istream_iterator</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::istream_iterator&lt;T,CharT,Traits,Distance&gt;::</span>istream_iterator</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-iterator.html">iterator</a>&lrm; | <a href="cpp-iterator-istream_iterator.html">istream iterator</a></span></div>
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp">istream_iterator<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-until-cxx11">(C++11 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> istream_iterator<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> istream_iterator<span class="br0">(</span> std<span class="sy4">::</span><span class="me2">default_sentinel_t</span> <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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<div><span class="mw-geshi cpp source-cpp">istream_iterator<span class="br0">(</span> istream_type<span class="sy3">&amp;</span> stream <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(3)</td>
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<td rowspan="142">(4)</td>
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<div><span class="mw-geshi cpp source-cpp">istream_iterator<span class="br0">(</span> <span class="kw4">const</span> istream_iterator<span class="sy3">&amp;</span> other <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
<td><span class="t-mark-rev t-until-cxx11">(C++11 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp">istream_iterator<span class="br0">(</span> <span class="kw4">const</span> istream_iterator<span class="sy3">&amp;</span> other <span class="br0">)</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<div class="t-li1"><span class="t-li">1)</span> &#26500;&#36896;&#27969;&#23614;&#36845;&#20195;&#22120;<span class="t-rev-inl t-since-cxx11"><span>&#65292;&#20540;&#21021;&#22987;&#21270;&#23384;&#20648;&#30340;&#20540;&#12290;&#33509;&#23450;&#20041; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">auto</span> x <span class="sy1">=</span> T<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></span> &#20013;&#30340;&#21021;&#22987;&#21270;&#22120;&#26159;&#24120;&#37327;&#21021;&#22987;&#21270;&#22120;&#65292;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#20026; constexpr</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></span></span>&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#21021;&#22987;&#21270;&#36845;&#20195;&#22120;&#24182;&#20110;&#25968;&#25454;&#25104;&#21592;&#20013;&#23384;&#20648; <code>stream</code> &#30340;&#22320;&#22336;&#12290;&#20877;&#20174;&#36755;&#20837;&#27969;&#36827;&#34892;&#39318;&#27425;&#35835;&#21462;&#20197;&#21021;&#22987;&#21270;&#32531;&#20914;&#25968;&#25454;&#25104;&#21592;&#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#26500;&#36896; <code>other</code> &#30340;&#21103;&#26412;&#12290;<span class="t-rev-inl t-since-cxx11"><span>&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_copy_constructible.html"><span class="kw534">std::<span class="me2">is_trivially_copy_constructible</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy4">::</span><span class="me2">value</span></span></span> &#20026; <code>true</code> &#65292;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#20026;&#24179;&#20961;&#22797;&#21046;&#26500;&#36896;&#20989;&#25968;&#12290;</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></span></span></div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>stream</td>
<td>-</td>
<td>&#29992;&#20110;&#21021;&#22987;&#21270; istream_iterator &#30340;&#27969;</td>
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<td>other</td>
<td>-</td>
<td>&#21516;&#31867;&#22411;&#30340;&#21478;&#19968; istream_iterator</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;iostream&gt;</span>
<span class="co2">#include &lt;iterator&gt;</span>
<span class="co2">#include &lt;algorithm&gt;</span>
<span class="co2">#include &lt;sstream&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-basic_istringstream.html"><span class="kw1735">std::<span class="me2">istringstream</span></span></a> stream<span class="br0">(</span><span class="st0">&quot;1 2 3 4 5&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-algorithm-copy.html"><span class="kw1582">std::<span class="me2">copy</span></span></a><span class="br0">(</span>
<a href="cpp-iterator-istream_iterator.html"><span class="kw668">std::<span class="me2">istream_iterator</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span><span class="br0">(</span>stream<span class="br0">)</span>,
<a href="cpp-iterator-istream_iterator.html"><span class="kw668">std::<span class="me2">istream_iterator</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span><span class="br0">(</span><span class="br0">)</span>,
<a href="cpp-iterator-ostream_iterator.html"><span class="kw670">std::<span class="me2">ostream_iterator</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span><span class="br0">(</span><a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a>, <span class="st0">&quot; &quot;</span><span class="br0">)</span>
<span class="br0">)</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">1 2 3 4 5</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>
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<th>DR</th>
<th>&#24212;&#29992;&#20110;</th>
<th>&#20986;&#29256;&#26102;&#30340;&#34892;&#20026;</th>
<th>&#27491;&#30830;&#34892;&#20026;</th>
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<td><a rel="nofollow" class="external text" href="https://wg21.link/P0738R2">P0738R2</a></td>
<td>C++98</td>
<td>&#39318;&#27425;&#35835;&#21462;&#21487;&#20197;&#24310;&#36831;&#21040;&#39318;&#27425;&#35299;&#24341;&#29992;</td>
<td>&#39318;&#27425;&#35835;&#21462;&#22312;&#26500;&#36896;&#20989;&#25968;&#20013;&#36827;&#34892;</td>
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