240 lines
26 KiB
HTML
240 lines
26 KiB
HTML
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<title>std::experimental::is_detected, std::experimental::detected_t, std::experimental::detected_or</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_experimental_is_detected 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::experimental::</span>is_detected, <span style="font-size:0.7em; line-height:130%">std::experimental::</span>detected_t, <span style="font-size:0.7em; line-height:130%">std::experimental::</span>detected_or</h1>
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-experimental.html">experimental</a></span></div>
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<div>定义于头文件 <code><a href="https://zh.cppreference.com/mwiki/index.php?title=cpp/header/experimental/type_traits&action=edit&redlink=1" class="new" title="cpp/header/experimental/type traits（页面不存在）"><experimental/type_traits></a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw1">using</span> is_detected <span class="sy1">=</span> <span class="coMULTI">/* see below */</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw1">using</span> detected_t <span class="sy1">=</span> <span class="coMULTI">/* see below */</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<tr class="t-dcl t-since-libfund_ts_2">
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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> Default, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw1">using</span> detected_or <span class="sy1">=</span> <span class="coMULTI">/* see below */</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<p>别名模板 <code>detected_or</code> 是拥有二个公开成员 typedef <code>value_t</code> 和 <code>type</code> 的未指定类类型的别名，它们定义如下：</p>
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<ul>
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<li>若<i>模板 id</i> <span class="t-c"><span class="mw-geshi cpp source-cpp">Op<span class="sy1"><</span>Args...<span class="sy1">></span></span></span> 代表合法类型，则 <code>value_t</code> 是 <span class="t-lc"><a href="cpp-types-integral_constant.html">std::true_type</a></span> 的别名，而 <code>type</code> 是 <span class="t-c"><span class="mw-geshi cpp source-cpp">Op<span class="sy1"><</span>Args...<span class="sy1">></span></span></span> 的别名；</li>
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<li>否则， <code>value_t</code> 是 <span class="t-lc"><a href="cpp-types-integral_constant.html">std::false_type</a></span> 的别名而 <code>type</code> 是 <code>Default</code> 的别名。</li>
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</ul>
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<p><br />
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别名模板 <code>is_detected</code> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">typename</span> detected_or<span class="sy1"><</span><a href="cpp-experimental-nonesuch.html"><span class="kw2414">std::<span class="me2">experimental</span><span class="sy4">::</span><span class="me2">nonesuch</span></span></a>, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_t</span></span></span> 。若<i>模板 id</i> <span class="t-c"><span class="mw-geshi cpp source-cpp">Op<span class="sy1"><</span>Args...<span class="sy1">></span></span></span> 代表合法类型，则它是 <span class="t-lc"><a href="cpp-types-integral_constant.html">std::true_type</a></span> 的别名；否则它是 <span class="t-lc"><a href="cpp-types-integral_constant.html">std::false_type</a></span> 的别名。</p>
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<p><br />
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别名模版 <code>detected_t</code> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">typename</span> detected_or<span class="sy1"><</span><a href="cpp-experimental-nonesuch.html"><span class="kw2414">std::<span class="me2">experimental</span><span class="sy4">::</span><span class="me2">nonesuch</span></span></a>, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span></span></span> 。若<i>模板 id</i> <span class="t-c"><span class="mw-geshi cpp source-cpp">Op<span class="sy1"><</span>Args...<span class="sy1">></span></span></span> 代表合法类型，则它是 <span class="t-c"><span class="mw-geshi cpp source-cpp">Op<span class="sy1"><</span>Args...<span class="sy1">></span></span></span> 的别名；否则它是类 <a href="cpp-experimental-nonesuch.html"><tt>std::experimental::nonesuch</tt></a> 的别名。</p>
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<h3><span class="mw-headline" id=".E9.A2.9D.E5.A4.96.E5.B7.A5.E5.85.B7">额外工具</span></h3>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> <span class="kw4">bool</span> is_detected_v <span class="sy1">=</span> is_detected<span class="sy1"><</span>Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<tr class="t-dcl t-since-libfund_ts_3">
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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">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> <span class="kw1">inline</span> <span class="kw4">bool</span> is_detected_v <span class="sy1">=</span> is_detected<span class="sy1"><</span>Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</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-libfund-ts-3 t-mark-ts">(库基础 TS v3)</span></td>
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</tr>
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</tbody>
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<tbody>
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<tr class="t-dcl t-since-libfund_ts_2">
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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> Default, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span> <span class="sy1">></span><br />
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<span class="kw1">using</span> detected_or_t <span class="sy1">=</span> <span class="kw1">typename</span> detected_or<span class="sy1"><</span>Default, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">type</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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<tr class="t-dcl t-since-libfund_ts_2">
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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> Expected, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br />
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<span class="kw1">using</span> is_detected_exact <span class="sy1">=</span> <a href="cpp-types-is_same.html"><span class="kw588">std::<span class="me2">is_same</span></span></a><span class="sy1"><</span>Expected, detected_t<span class="sy1"><</span>Op, Args...<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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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</tbody>
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<tbody class="t-dcl-rev">
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<tr class="t-dcl t-since-libfund_ts_2">
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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> Expected, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> <span class="kw4">bool</span> is_detected_exact_v <span class="sy1">=</span><br /></p>
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is_detected_exact<span class="sy1"><</span>Expected, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span><span class="sy4">;</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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<tr class="t-dcl t-since-libfund_ts_3">
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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> Expected, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> <span class="kw1">inline</span> <span class="kw4">bool</span> is_detected_exact_v <span class="sy1">=</span><br /></p>
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is_detected_exact<span class="sy1"><</span>Expected, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span><span class="sy4">;</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-libfund-ts-3 t-mark-ts">(库基础 TS v3)</span></td>
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</tr>
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</tbody>
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<tbody>
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<tr class="t-dcl t-since-libfund_ts_2">
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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> To, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br /></span>
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<p><span class="kw1">using</span> is_detected_convertible <span class="sy1">=</span><br /></p>
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<a href="cpp-types-is_convertible.html"><span class="kw592">std::<span class="me2">is_convertible</span></span></a><span class="sy1"><</span>detected_t<span class="sy1"><</span>Op, Args...<span class="sy1">></span>, To<span class="sy1">></span><span class="sy4">;</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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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</tbody>
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<tbody class="t-dcl-rev">
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<tr class="t-dcl t-since-libfund_ts_2">
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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> To, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> <span class="kw4">bool</span> is_detected_convertible_v <span class="sy1">=</span><br /></p>
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is_detected_convertible<span class="sy1"><</span>To, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span><span class="sy4">;</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-libfund-ts-2 t-mark-ts">(库基础 TS v2)</span></td>
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</tr>
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<tr class="t-dcl t-since-libfund_ts_3">
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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> To, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> <span class="kw1">inline</span> <span class="kw4">bool</span> is_detected_convertible_v <span class="sy1">=</span><br /></p>
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is_detected_convertible<span class="sy1"><</span>To, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span><span class="sy4">;</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-libfund-ts-3 t-mark-ts">(库基础 TS v3)</span></td>
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</tr>
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</tbody>
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<tbody>
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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>别名模版 <code>is_detected_exact</code> 检查 <span class="t-c"><span class="mw-geshi cpp source-cpp">detected_t<span class="sy1"><</span>Op, Args...<span class="sy1">></span></span></span> 是否为 <code>Expected</code> 。</p>
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<p>别名模板 <code>is_detected_convertible</code> 检查 <span class="t-c"><span class="mw-geshi cpp source-cpp">detected_t<span class="sy1"><</span>Op, Args...<span class="sy1">></span></span></span> 是否可转换为 <code>To</code> 。</p>
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<h3><span class="mw-headline" id=".E5.8F.AF.E8.83.BD.E7.9A.84.E5.AE.9E.E7.8E.B0">可能的实现</span></h3>
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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="kw1">namespace</span> detail <span class="br0">{</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> Default, <span class="kw1">class</span> AlwaysVoid,
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<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span>
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<span class="kw1">struct</span> detector <span class="br0">{</span>
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<span class="kw1">using</span> value_t <span class="sy1">=</span> <a href="cpp-types-integral_constant.html"><span class="kw650">std::<span class="me2">false_type</span></span></a><span class="sy4">;</span>
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<span class="kw1">using</span> type <span class="sy1">=</span> Default<span class="sy4">;</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> Default, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span>
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<span class="kw1">struct</span> detector<span class="sy1"><</span>Default, <a href="cpp-types-void_t.html"><span class="kw632">std::<span class="me2">void_t</span></span></a><span class="sy1"><</span>Op<span class="sy1"><</span>Args...<span class="sy1">>></span>, Op, Args...<span class="sy1">></span> <span class="br0">{</span>
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<span class="co1">// 注意 std::void_t 是 C++17 特性</span>
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<span class="kw1">using</span> value_t <span class="sy1">=</span> <a href="cpp-types-integral_constant.html"><span class="kw649">std::<span class="me2">true_type</span></span></a><span class="sy4">;</span>
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<span class="kw1">using</span> type <span class="sy1">=</span> Op<span class="sy1"><</span>Args...<span class="sy1">></span><span class="sy4">;</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="br0">}</span> <span class="co1">// namespace detail</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span>
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<span class="kw1">using</span> is_detected <span class="sy1">=</span> <span class="kw1">typename</span> detail<span class="sy4">::</span><span class="me2">detector</span><span class="sy1"><</span>nonesuch, <span class="kw4">void</span>, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">value_t</span><span class="sy4">;</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span>
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<span class="kw1">using</span> detected_t <span class="sy1">=</span> <span class="kw1">typename</span> detail<span class="sy4">::</span><span class="me2">detector</span><span class="sy1"><</span>nonesuch, <span class="kw4">void</span>, Op, Args...<span class="sy1">></span><span class="sy4">::</span><span class="me2">type</span><span class="sy4">;</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> Default, <span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span>...<span class="sy1">></span> <span class="kw1">class</span> Op, <span class="kw1">class</span>... <span class="me1">Args</span><span class="sy1">></span>
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<span class="kw1">using</span> detected_or <span class="sy1">=</span> detail<span class="sy4">::</span><span class="me2">detector</span><span class="sy1"><</span>Default, <span class="kw4">void</span>, Op, Args...<span class="sy1">></span><span class="sy4">;</span></pre></div>
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</div>
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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 <experimental/type_traits></span>
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<span class="co2">#include <cstddef></span>
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<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span>
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<span class="kw1">using</span> copy_assign_t <span class="sy1">=</span> decltype<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="sy3">&</span><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">=</span> <a href="cpp-utility-declval.html"><span class="kw1120">std::<span class="me2">declval</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">struct</span> Meow <span class="br0">{</span> <span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">struct</span> Purr <span class="br0">{</span> <span class="kw4">void</span> operator<span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> Purr<span class="sy3">&</span><span class="br0">)</span> <span class="sy1">=</span> delete<span class="sy4">;</span> <span class="br0">}</span><span class="sy4">;</span>
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static_assert<span class="br0">(</span>std<span class="sy4">::</span><span class="me2">experimental</span><span class="sy4">::</span><span class="me2">is_detected</span><span class="sy1"><</span>copy_assign_t, Meow<span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span>,
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<span class="st0">"Meow should be copy assignable!"</span><span class="br0">)</span><span class="sy4">;</span>
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static_assert<span class="br0">(</span><span class="sy3">!</span>std<span class="sy4">::</span><span class="me2">experimental</span><span class="sy4">::</span><span class="me2">is_detected_v</span><span class="sy1"><</span>copy_assign_t, Purr<span class="sy1">></span>,
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<span class="st0">"Purr should not be copy assignable!"</span><span class="br0">)</span><span class="sy4">;</span>
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static_assert<span class="br0">(</span>std<span class="sy4">::</span><span class="me2">experimental</span><span class="sy4">::</span><span class="me2">is_detected_exact_v</span><span class="sy1"><</span>Meow<span class="sy3">&</span>, copy_assign_t, Meow<span class="sy1">></span>,
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<span class="st0">"Copy assignment of Meow should return Meow&!"</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span>
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<span class="kw1">using</span> diff_t <span class="sy1">=</span> <span class="kw1">typename</span> T<span class="sy4">::</span><span class="me2">difference_type</span><span class="sy4">;</span>
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<span class="kw1">template</span> <span class="sy1"><</span><span class="kw1">class</span> Ptr<span class="sy1">></span>
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<span class="kw1">using</span> difference_type <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">experimental</span><span class="sy4">::</span><span class="me2">detected_or_t</span><span class="sy1"><</span><a href="cpp-types-ptrdiff_t.html"><span class="kw101">std::<span class="me2">ptrdiff_t</span></span></a>, diff_t, Ptr<span class="sy1">></span><span class="sy4">;</span>
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<span class="kw1">struct</span> Woof <span class="br0">{</span> <span class="kw1">using</span> difference_type <span class="sy1">=</span> <span class="kw4">int</span><span class="sy4">;</span> <span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">struct</span> Bark <span class="br0">{</span><span class="br0">}</span><span class="sy4">;</span>
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static_assert<span class="br0">(</span><a href="cpp-types-is_same.html"><span class="kw588">std::<span class="me2">is_same</span></span></a><span class="sy1"><</span>difference_type<span class="sy1"><</span>Woof<span class="sy1">></span>, <span class="kw4">int</span><span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span>,
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<span class="st0">"Woof's difference_type should be int!"</span><span class="br0">)</span><span class="sy4">;</span>
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static_assert<span class="br0">(</span><a href="cpp-types-is_same.html"><span class="kw588">std::<span class="me2">is_same</span></span></a><span class="sy1"><</span>difference_type<span class="sy1"><</span>Bark<span class="sy1">></span>, <a href="cpp-types-ptrdiff_t.html"><span class="kw101">std::<span class="me2">ptrdiff_t</span></span></a><span class="sy1">></span><span class="sy4">::</span><span class="me2">value</span>,
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<span class="st0">"Bark's difference_type should be ptrdiff_t!"</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span><span class="br0">}</span></pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
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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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