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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::slice_array&lt;T&gt;::</span>operator=</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-numeric.html">numeric</a>&lrm; | <a href="cpp-numeric-valarray.html">valarray</a>&lrm; | <a href="cpp-numeric-valarray-slice_array.html">slice array</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&amp;</span> value <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td>(1)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy3">&amp;</span> val_arr <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> slice_array<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> slice_array<span class="sy3">&amp;</span> sl_arr<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td>(3)</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#23558;&#20540;&#36171;&#20540;&#32473;&#25152;&#26377;&#34987;&#24341;&#29992;&#20803;&#32032;&#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#23558; <code>value</code> &#36171;&#20540;&#32473;&#25152;&#26377;&#20803;&#32032;&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#23558; <code>val_arr</code> &#30340;&#20803;&#32032;&#36171;&#20540;&#32473; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#25152;&#24341;&#29992;&#30340;&#20803;&#32032;&#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#23558;&#33258; <code>sl_arr</code> &#36873;&#25321;&#30340;&#20803;&#32032;&#36171;&#20540;&#32473; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#25152;&#24341;&#29992;&#30340;&#20803;&#32032;&#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>value</td>
<td>-</td>
<td>&#36171;&#20540;&#32473;&#25152;&#26377;&#34987;&#24341;&#29992;&#20803;&#32032;&#30340;&#20540;</td>
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<td>val_arr</td>
<td>-</td>
<td>&#29992;&#20197;&#36171;&#20540;&#30340; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a></span></span></td>
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<td>sl_arr</td>
<td>-</td>
<td>&#29992;&#20197;&#36171;&#20540;&#30340; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-numeric-valarray-slice_array.html"><span class="kw1476">std::<span class="me2">slice_array</span></span></a></span></span></td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<div class="t-li1"><span class="t-li">1-2)</span> &#65288;&#26080;&#65289;</div>
<div class="t-li1"><span class="t-li">3)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span></div>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<p>&#21487;&#33021;&#25243;&#20986;&#23454;&#29616;&#23450;&#20041;&#30340;&#24322;&#24120;&#12290;</p>
<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;valarray&gt;</span>
<span class="kw4">void</span> print<span class="br0">(</span><span class="kw4">char</span> <span class="kw4">const</span><span class="sy2">*</span> remark, <a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> <span class="kw4">const</span><span class="sy3">&amp;</span> v <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><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> remark<span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>v.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> <span class="nu0">0</span><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> <span class="st0">&quot;:&quot;</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> e <span class="sy4">:</span> v<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> <span class="st0">&#39; &#39;</span> <span class="sy1">&lt;&lt;</span> e<span class="sy4">;</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> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> v1<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="nu0">6</span>,<span class="nu0">7</span>,<span class="nu0">8</span><span class="br0">}</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray-slice_array.html"><span class="kw1476">std::<span class="me2">slice_array</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> s1 <span class="sy1">=</span> v1<span class="br0">[</span><a href="cpp-numeric-valarray-slice.html"><span class="kw1474">std::<span class="me2">slice</span></span></a><span class="br0">(</span><span class="nu0">1</span>, <span class="nu0">4</span>, <span class="nu0">2</span><span class="br0">)</span><span class="br0">]</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v1&quot;</span>, v1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s1&quot;</span>, s1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>(1) operator=( const T&amp; )&quot;</span><span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s1 = 42&quot;</span><span class="br0">)</span><span class="sy4">;</span>
s1 <span class="sy1">=</span> <span class="nu0">42</span><span class="sy4">;</span> <span class="co1">// (1)</span>
print<span class="br0">(</span><span class="st0">&quot;s1&quot;</span>, s1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v1&quot;</span>, v1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>(2) operator=( const std::valarray&lt;T&gt;&amp; )&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> v2<span class="br0">{</span><span class="nu0">10</span>,<span class="nu0">11</span>,<span class="nu0">12</span>,<span class="nu0">13</span>,<span class="nu0">14</span>,<span class="nu0">15</span><span class="br0">}</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v2&quot;</span>, v2<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s1 = v2&quot;</span><span class="br0">)</span><span class="sy4">;</span>
s1 <span class="sy1">=</span> v2<span class="sy4">;</span> <span class="co1">// (2)</span>
print<span class="br0">(</span><span class="st0">&quot;s1&quot;</span>, s1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v1&quot;</span>, v1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>(3) operator=( const slice_array&amp; )&quot;</span><span class="br0">)</span><span class="sy4">;</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="nu0">6</span>,<span class="nu0">7</span>,<span class="nu0">8</span><span class="br0">}</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray-slice_array.html"><span class="kw1476">std::<span class="me2">slice_array</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> s2 <span class="sy1">=</span> v1<span class="br0">[</span><a href="cpp-numeric-valarray-slice.html"><span class="kw1474">std::<span class="me2">slice</span></span></a><span class="br0">(</span><span class="nu0">0</span>, <span class="nu0">4</span>, <span class="nu0">1</span><span class="br0">)</span><span class="br0">]</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray-slice_array.html"><span class="kw1476">std::<span class="me2">slice_array</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> s3 <span class="sy1">=</span> v2<span class="br0">[</span><a href="cpp-numeric-valarray-slice.html"><span class="kw1474">std::<span class="me2">slice</span></span></a><span class="br0">(</span><span class="nu0">1</span>, <span class="nu0">4</span>, <span class="nu0">1</span><span class="br0">)</span><span class="br0">]</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v1&quot;</span>, v1<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v2&quot;</span>, v2<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s2&quot;</span>, s2<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s3&quot;</span>, s3<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;s2 = s3&quot;</span><span class="br0">)</span><span class="sy4">;</span>
s2 <span class="sy1">=</span> s3<span class="sy4">;</span> <span class="co1">// (3) &#27880;&#65306; LHS &#19982; RHS &#24517;&#39035;&#25317;&#26377;&#30456;&#21516;&#22823;&#23567;</span>
print<span class="br0">(</span><span class="st0">&quot;s2&quot;</span>, s2<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="st0">&quot;v1&quot;</span>, v1<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">v1: 1 2 3 4 5 6 7 8
s1: 2 4 6 8
(1) operator=( const T&amp; )
s1 = 42
s1: 42 42 42 42
v1: 1 42 3 42 5 42 7 42
(2) operator=( const std::valarray&lt;T&gt;&amp; )
v2: 10 11 12 13 14 15
s1 = v2
s1: 10 11 12 13
v1: 1 10 3 11 5 12 7 13
(3) operator=( const slice_array&amp; )
v1: 1 2 3 4 5 6 7 8
v2: 10 11 12 13 14 15
s2: 1 2 3 4
s3: 11 12 13 14
s2 = s3
s2: 11 12 13 14
v1: 11 12 13 14 5 6 7 8</pre></div>
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