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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::regex_traits&lt;CharT&gt;::</span>lookup_classname</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-regex.html">regex</a>&lrm; | <a href="cpp-regex-regex_traits.html">regex traits</a></span></div>
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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> ForwardIt <span class="sy1">&gt;</span><br /></span>
<p>char_class_type lookup_classname<span class="br0">(</span> ForwardIt first,<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ForwardIt last,<br /></p>
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span class="kw4">bool</span> icase <span class="sy1">=</span> <span class="kw2">false</span> <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></div>
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<p>&#33509;&#23383;&#31526;&#24207;&#21015; <code>[first, last)</code> &#34920;&#31034;&#24403;&#21069;&#24863;&#26579;&#30340; locale &#20013;&#21512;&#27861;&#30340;&#23383;&#31526;&#31867;&#21517;&#31216;&#65288;&#21363;&#27491;&#21017;&#34920;&#36798;&#24335;&#20013; <code>[:</code> &#19982; <code>:]</code> &#20043;&#38388;&#30340;&#23383;&#31526;&#20018;&#65289;&#65292;&#21017;&#36820;&#22238;&#34920;&#31034;&#27492;&#23383;&#31526;&#31867;&#30340;&#23454;&#29616;&#23450;&#20041;&#20540;&#12290;&#21542;&#21017;&#65292;&#36820;&#22238;&#38646;&#12290;</p>
<p>&#33509;&#21442;&#25968; <code>icase</code> &#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#65292;&#21017;&#23383;&#31526;&#31867;&#24573;&#30053;&#23383;&#31526;&#22823;&#23567;&#20889;&#65292;&#20363;&#22914;&#24102; <span class="t-lc"><a href="cpp-regex-syntax_option_type.html">std::regex_constants::icase</a></span> &#30340;&#27491;&#21017;&#34920;&#36798;&#24335; <code>[:lower:]</code> &#29983;&#25104;&#20197; <code>[first, last)</code> &#25351;&#31034;&#23383;&#31526;&#20018; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;lower&quot;</span></span></span> &#65292;&#19988; <span class="t-c"><span class="mw-geshi cpp source-cpp">icase <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#30340; <code>regex_traits&lt;&gt;::lookup_classname()</code> &#35843;&#29992;&#12290;&#27492;&#35843;&#29992;&#36820;&#22238;&#19982;&#24102; <span class="t-c"><span class="mw-geshi cpp source-cpp">icase <span class="sy1">==</span> <span class="kw2">false</span></span></span> &#30340;&#27491;&#21017;&#34920;&#36798;&#24335; <code>[:alpha:]</code> &#25152;&#29983;&#25104;&#32773;&#30456;&#21516;&#20301;&#25513;&#30721;&#12290;</p>
<p>&#22987;&#32456;&#20197;&#31364;&#21644;&#23485;&#23383;&#31526;&#24418;&#24335;&#36776;&#35748;&#19979;&#21015;&#23383;&#31526;&#31867;&#65292;&#24182;&#36820;&#22238;&#22914;&#19979;&#30340;&#65292;&#24863;&#26579;&#30340; locale &#30340; <span class="t-lc"><a href="cpp-locale-ctype.html">std::ctype</a></span> &#24179;&#38754;&#25152;&#33719;&#24471;&#30340;&#21305;&#37197;&#20998;&#31867;&#25152;&#23545;&#24212;&#30340;&#20998;&#31867;&#65288;&#26377; <span class="t-c"><span class="mw-geshi cpp source-cpp">icase <span class="sy1">==</span> <span class="kw2">false</span></span></span> &#65289;&#65306;</p>
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<td>&#23383;&#31526;&#31867;</td>
<td><span class="t-lc"><a href="cpp-locale-ctype.html">std::ctype</a></span> &#20998;&#31867;</td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;alnum&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::alnum</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;alpha&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::alpha</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;blank&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::blank</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;cntrl&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::cntrl</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;digit&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::digit</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;graph&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::graph</a></span></td>
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<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;lower&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::lower</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;print&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::print</a></span></td>
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<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;punct&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::punct</a></span></td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;space&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::space</a></span></td>
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<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;upper&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::upper</a></span></td>
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<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;xdigit&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::xdigit</a></span></td>
</tr>
<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;d&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::digit</a></span></td>
</tr>
<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;s&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::space</a></span></td>
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<tr class="t-dsc">
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;w&quot;</span></span></span></td>
<td><span class="t-lc"><a href="cpp-locale-ctype_base.html">std::ctype_base::alnum</a></span> &#21487;&#36873;&#22320;&#21152;&#19978;&#24102; &#39;_&#39;</td>
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<p>&#23545;&#23383;&#31526;&#20018; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;w&quot;</span></span></span> &#36820;&#22238;&#30340;&#20998;&#31867;&#21487;&#20197;&#20934;&#30830;&#22320;&#19982; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;alnum&quot;</span></span></span> &#30456;&#21516;&#65292;&#35813;&#24773;&#20917;&#19979; <span class="t-lc"><a href="cpp-regex-regex_traits-isctype.html">isctype()</a></span> &#26174;&#24335;&#21152;&#19978; &#39;_&#39; &#12290;</p>
<p>&#31995;&#32479;&#25552;&#20379;&#30340;&#26412;&#22320;&#29615;&#22659;&#21487;&#25552;&#20379;&#39069;&#22806;&#20998;&#31867;&#65292;&#22914; <span class="t-lc">&quot;jdigit&quot;</span> &#25110; <span class="t-lc">&quot;jkanji&quot;</span> &#65288;&#35813;&#24773;&#20917;&#19979;&#23427;&#20204;&#20134;&#21487;&#36890;&#36807; <span class="t-lc"><a href="cpp-string-wide-wctype.html">std::wctype</a></span> &#35775;&#38382;&#65289;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<table class="t-par-begin">
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<td>first, last</td>
<td>-</td>
<td>&#19968;&#23545;&#36845;&#20195;&#22120;&#65292;&#30830;&#23450;&#34920;&#31034;&#23383;&#31526;&#31867;&#21517;&#30340;&#23383;&#31526;&#24207;&#21015;</td>
</tr>
<tr class="t-par">
<td>icase</td>
<td>-</td>
<td>&#33509;&#20026; true &#65292;&#21017;&#24573;&#30053;&#23383;&#31526;&#20998;&#31867;&#20013;&#30340;&#22823;&#23567;&#20889;&#21306;&#21035;</td>
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<tr class="t-par-hitem">
<td colspan="3">&#31867;&#22411;&#35201;&#27714;</td>
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<tr class="t-par-req">
<td colspan="3">-
<div class="spacer"></div>
<code>ForwardIt</code> &#24517;&#39035;&#28385;&#36275;<a href="cpp-named_req-ForwardIterator.html"><span style="font-style:italic">&#32769;&#24335;&#21521;&#21069;&#36845;&#20195;&#22120;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(LegacyForwardIterator)</span></a> &#30340;&#35201;&#27714;&#12290;</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>
<p>&#20197;&#32473;&#23450;&#30340;&#23383;&#31526;&#31867;&#30830;&#23450;&#30340;&#34920;&#31034;&#23383;&#31526;&#20998;&#31867;&#30340;&#20301;&#25513;&#30721;&#65292;&#25110;&#33509;&#31867;&#26410;&#30693;&#21017;&#20026; <code>char_class_type()</code> &#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<p>&#28436;&#31034;&#23450;&#21046; regex_traits &#30340; lookup_classname/isctype &#23454;&#29616;</p>
<div class="t-example-live-link"></div>
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<div class="cpp source-cpp">
<pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;locale&gt;</span>
<span class="co2">#include &lt;regex&gt;</span>
<span class="co2">#include &lt;cwctype&gt;</span>
<span class="co1">// &#27492;&#23450;&#21046;&#27491;&#21017;&#34920;&#36798;&#24335;&#29305;&#24615;&#20197; wctype/iswctype &#23454;&#29616; lookup_classname/isctype</span>
<span class="kw1">struct</span> wctype_traits <span class="sy4">:</span> <a href="cpp-regex-regex_traits.html"><span class="kw2026">std::<span class="me2">regex_traits</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span><span class="sy1">&gt;</span>
<span class="br0">{</span>
<span class="kw1">using</span> char_class_type <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">wctype_t</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> It<span class="sy1">&gt;</span>
char_class_type lookup_classname<span class="br0">(</span>It first, It last, <span class="kw4">bool</span><span class="sy1">=</span><span class="kw2">false</span><span class="br0">)</span> <span class="kw4">const</span> <span class="br0">{</span>
<span class="kw1">return</span> <a href="cpp-string-wide-wctype.html"><span class="kw1193">std::<span class="me2">wctype</span></span></a><span class="br0">(</span><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="br0">(</span>first, last<span class="br0">)</span>.<span class="me1">c_str</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">bool</span> isctype<span class="br0">(</span><span class="kw4">wchar_t</span> c, char_class_type f<span class="br0">)</span> <span class="kw4">const</span> <span class="br0">{</span>
<span class="kw1">return</span> <a href="cpp-string-wide-iswctype.html"><span class="kw1192">std::<span class="me2">iswctype</span></span></a><span class="br0">(</span>c, f<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
std<span class="sy4">::</span><span class="me2">locale</span><span class="sy4">::</span><span class="me2">global</span><span class="br0">(</span><a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a><span class="br0">(</span><span class="st0">&quot;ja_JP.utf8&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a>.<span class="me1">sync_with_stdio</span><span class="br0">(</span><span class="kw2">false</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a>.<span class="me1">imbue</span><span class="br0">(</span><a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-regex-match_results.html"><span class="kw2011">std::<span class="me2">wsmatch</span></span></a> m<span class="sy4">;</span>
<a href="cpp-string-basic_string.html"><span class="kw1232">std::<span class="me2">wstring</span></span></a> in <span class="sy1">=</span> L<span class="st0">&quot;&#12369;&#12418;&#12398;&#12501;&#12524;&#12531;&#12474;&quot;</span><span class="sy4">;</span>
<span class="co1">// &#21305;&#37197;&#25152;&#26377;&#23383;&#31526;&#65288;&#23427;&#20204;&#34987;&#20998;&#31867;&#20026; alnum &#65289;</span>
<a href="cpp-regex-regex_search.html"><span class="kw2013">std::<span class="me2">regex_search</span></span></a><span class="br0">(</span>in, m, <a href="cpp-regex-basic_regex.html"><span class="kw2001">std::<span class="me2">wregex</span></span></a><span class="br0">(</span>L<span class="st0">&quot;([[:alnum:]]+)&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;alnums: &quot;</span> <span class="sy1">&lt;&lt;</span> m<span class="br0">[</span><span class="nu0">1</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">// &#25171;&#21360; &quot;&#12369;&#12418;&#12398;&#12501;&#12524;&#12531;&#12474;&quot;</span>
<span class="co1">// &#21482;&#21305;&#37197;&#29255;&#20551;&#21517;</span>
<a href="cpp-regex-regex_search.html"><span class="kw2013">std::<span class="me2">regex_search</span></span></a><span class="br0">(</span>in, m,
<a href="cpp-regex-basic_regex.html"><span class="kw1999">std::<span class="me2">basic_regex</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span>, wctype_traits<span class="sy1">&gt;</span><span class="br0">(</span>L<span class="st0">&quot;([[:jkata:]]+)&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;katakana: &quot;</span> <span class="sy1">&lt;&lt;</span> m<span class="br0">[</span><span class="nu0">1</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">// &#25171;&#21360; &quot;&#12501;&#12524;&#12531;&#12474;&quot;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">alnums: &#12369;&#12418;&#12398;&#12501;&#12524;&#12531;&#12474;
katakana: &#12501;&#12524;&#12531;&#12474;</pre></div>
</div>
</div>
<p><br /></p>
<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-regex-regex_traits-isctype.html"><span class="t-lines"><span>isctype</span></span></a></div>
</div>
</td>
<td>&#25351;&#31034;&#23383;&#31526;&#31867;&#20013;&#30340;&#25104;&#21592;&#20851;&#31995;&#25351;&#31034;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-string-wide-wctype.html"><span class="t-lines"><span>wctype</span></span></a></div>
</div>
</td>
<td>&#22312;&#24403;&#21069; C &#26412;&#22320;&#29615;&#22659;&#20013;&#26597;&#25214;&#23383;&#31526;&#20998;&#31867;&#31867;&#21035;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>