text: //===----------------------------------------------------------------------===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  
  // <regex>
  
  // template <class charT> struct regex_traits;
  
  // template <class ForwardIterator>
  //   char_class_type
  //   lookup_classname(ForwardIterator first, ForwardIterator last,
  //                    bool icase = false) const;
  
  #include <regex.hxx>
  #include <cassert.hxx>
  #include "test_macros.h"
  #include "test_iterators.h"
  
  template <class char_type>
  void
  test(const char_type* A,
       typename std::regex_traits<char_type>::char_class_type expected,
       bool icase = false)
  {
      typedef typename std::regex_traits<char_type>::char_class_type char_class_type;
      std::regex_traits<char_type> t;
      typedef forward_iterator<const char_type*> F;
      char_class_type result = t.lookup_classname(F(A), F(A + t.length(A)), icase);
      assert(result == expected);
  }
  
  template <class char_type>
  void
  test_w(const char_type* A,
         typename std::regex_traits<char_type>::char_class_type expected,
          bool icase = false)
  {
      typedef typename std::regex_traits<char_type>::char_class_type char_class_type;
      std::regex_traits<char_type> t;
      typedef forward_iterator<const char_type*> F;
      char_class_type result = t.lookup_classname(F(A), F(A + t.length(A)), icase);
      assert((result & expected) == expected);
      LIBCPP_ASSERT((expected | std::regex_traits<char_type>::__regex_word) == result);
  
      const bool matches_underscore = t.isctype('_', result);
      if (result != expected)
        assert(matches_underscore && "expected to match underscore");
      else
        assert(!matches_underscore && "should not match underscore");
  }
  
  int main(int, char**)
  {
  //  if __regex_word is not distinct from all the classes, bad things happen
  //  See https://bugs.llvm.org/show_bug.cgi?id=26476 for an example.
      LIBCPP_ASSERT((std::ctype_base::space  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::print  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::cntrl  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::upper  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::lower  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::alpha  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::digit  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::punct  & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::xdigit & std::regex_traits<char>::__regex_word) == 0);
      LIBCPP_ASSERT((std::ctype_base::blank  & std::regex_traits<char>::__regex_word) == 0);
  
      test("d", std::ctype_base::digit);
      test("D", std::ctype_base::digit);
      test("d", std::ctype_base::digit, true);
      test("D", std::ctype_base::digit, true);
  
      test_w("w", std::ctype_base::alnum
                | std::ctype_base::upper | std::ctype_base::lower);
      test_w("W", std::ctype_base::alnum
                | std::ctype_base::upper | std::ctype_base::lower);
      test_w("w", std::ctype_base::alnum
                | std::ctype_base::upper | std::ctype_base::lower, true);
      test_w("W", std::ctype_base::alnum
                | std::ctype_base::upper | std::ctype_base::lower, true);
  
      test("s", std::ctype_base::space);
      test("S", std::ctype_base::space);
      test("s", std::ctype_base::space, true);
      test("S", std::ctype_base::space, true);
  
      test("alnum", std::ctype_base::alnum);
      test("AlNum", std::ctype_base::alnum);
      test("alnum", std::ctype_base::alnum, true);
      test("AlNum", std::ctype_base::alnum, true);
  
      test("alpha", std::ctype_base::alpha);
      test("Alpha", std::ctype_base::alpha);
      test("alpha", std::ctype_base::alpha, true);
      test("Alpha", std::ctype_base::alpha, true);
  
      test("blank", std::ctype_base::blank);
      test("Blank", std::ctype_base::blank);
      test("blank", std::ctype_base::blank, true);
      test("Blank", std::ctype_base::blank, true);
  
      test("cntrl", std::ctype_base::cntrl);
      test("Cntrl", std::ctype_base::cntrl);
      test("cntrl", std::ctype_base::cntrl, true);
      test("Cntrl", std::ctype_base::cntrl, true);
  
      test("digit", std::ctype_base::digit);
      test("Digit", std::ctype_base::digit);
      test("digit", std::ctype_base::digit, true);
      test("Digit", std::ctype_base::digit, true);
  
      test("digit", std::ctype_base::digit);
      test("DIGIT", std::ctype_base::digit);
      test("digit", std::ctype_base::digit, true);
      test("Digit", std::ctype_base::digit, true);
  
      test("graph", std::ctype_base::graph);
      test("GRAPH", std::ctype_base::graph);
      test("graph", std::ctype_base::graph, true);
      test("Graph", std::ctype_base::graph, true);
  
      test("lower", std::ctype_base::lower);
      test("LOWER", std::ctype_base::lower);
      test("lower", std::ctype_base::lower | std::ctype_base::alpha, true);
      test("Lower", std::ctype_base::lower | std::ctype_base::alpha, true);
  
      test("print", std::ctype_base::print);
      test("PRINT", std::ctype_base::print);
      test("print", std::ctype_base::print, true);
      test("Print", std::ctype_base::print, true);
  
      test("punct", std::ctype_base::punct);
      test("PUNCT", std::ctype_base::punct);
      test("punct", std::ctype_base::punct, true);
      test("Punct", std::ctype_base::punct, true);
  
      test("space", std::ctype_base::space);
      test("SPACE", std::ctype_base::space);
      test("space", std::ctype_base::space, true);
      test("Space", std::ctype_base::space, true);
  
      test("upper", std::ctype_base::upper);
      test("UPPER", std::ctype_base::upper);
      test("upper", std::ctype_base::upper | std::ctype_base::alpha, true);
      test("Upper", std::ctype_base::upper | std::ctype_base::alpha, true);
  
      test("xdigit", std::ctype_base::xdigit);
      test("XDIGIT", std::ctype_base::xdigit);
      test("xdigit", std::ctype_base::xdigit, true);
      test("Xdigit", std::ctype_base::xdigit, true);
  
      test("dig", std::ctype_base::mask());
      test("", std::ctype_base::mask());
      test("digits", std::ctype_base::mask());
  
      test(L"d", std::ctype_base::digit);
      test(L"D", std::ctype_base::digit);
      test(L"d", std::ctype_base::digit, true);
      test(L"D", std::ctype_base::digit, true);
  
      test_w(L"w", std::ctype_base::alnum
                        | std::ctype_base::upper | std::ctype_base::lower);
      test_w(L"W", std::ctype_base::alnum
                        | std::ctype_base::upper | std::ctype_base::lower);
      test_w(L"w", std::ctype_base::alnum
                        | std::ctype_base::upper | std::ctype_base::lower, true);
      test_w(L"W", std::ctype_base::alnum
                        | std::ctype_base::upper | std::ctype_base::lower, true);
  
      test(L"s", std::ctype_base::space);
      test(L"S", std::ctype_base::space);
      test(L"s", std::ctype_base::space, true);
      test(L"S", std::ctype_base::space, true);
  
      test(L"alnum", std::ctype_base::alnum);
      test(L"AlNum", std::ctype_base::alnum);
      test(L"alnum", std::ctype_base::alnum, true);
      test(L"AlNum", std::ctype_base::alnum, true);
  
      test(L"alpha", std::ctype_base::alpha);
      test(L"Alpha", std::ctype_base::alpha);
      test(L"alpha", std::ctype_base::alpha, true);
      test(L"Alpha", std::ctype_base::alpha, true);
  
      test(L"blank", std::ctype_base::blank);
      test(L"Blank", std::ctype_base::blank);
      test(L"blank", std::ctype_base::blank, true);
      test(L"Blank", std::ctype_base::blank, true);
  
      test(L"cntrl", std::ctype_base::cntrl);
      test(L"Cntrl", std::ctype_base::cntrl);
      test(L"cntrl", std::ctype_base::cntrl, true);
      test(L"Cntrl", std::ctype_base::cntrl, true);
  
      test(L"digit", std::ctype_base::digit);
      test(L"Digit", std::ctype_base::digit);
      test(L"digit", std::ctype_base::digit, true);
      test(L"Digit", std::ctype_base::digit, true);
  
      test(L"digit", std::ctype_base::digit);
      test(L"DIGIT", std::ctype_base::digit);
      test(L"digit", std::ctype_base::digit, true);
      test(L"Digit", std::ctype_base::digit, true);
  
      test(L"graph", std::ctype_base::graph);
      test(L"GRAPH", std::ctype_base::graph);
      test(L"graph", std::ctype_base::graph, true);
      test(L"Graph", std::ctype_base::graph, true);
  
      test(L"lower", std::ctype_base::lower);
      test(L"LOWER", std::ctype_base::lower);
      test(L"lower", std::ctype_base::lower | std::ctype_base::alpha, true);
      test(L"Lower", std::ctype_base::lower | std::ctype_base::alpha, true);
  
      test(L"print", std::ctype_base::print);
      test(L"PRINT", std::ctype_base::print);
      test(L"print", std::ctype_base::print, true);
      test(L"Print", std::ctype_base::print, true);
  
      test(L"punct", std::ctype_base::punct);
      test(L"PUNCT", std::ctype_base::punct);
      test(L"punct", std::ctype_base::punct, true);
      test(L"Punct", std::ctype_base::punct, true);
  
      test(L"space", std::ctype_base::space);
      test(L"SPACE", std::ctype_base::space);
      test(L"space", std::ctype_base::space, true);
      test(L"Space", std::ctype_base::space, true);
  
      test(L"upper", std::ctype_base::upper);
      test(L"UPPER", std::ctype_base::upper);
      test(L"upper", std::ctype_base::upper | std::ctype_base::alpha, true);
      test(L"Upper", std::ctype_base::upper | std::ctype_base::alpha, true);
  
      test(L"xdigit", std::ctype_base::xdigit);
      test(L"XDIGIT", std::ctype_base::xdigit);
      test(L"xdigit", std::ctype_base::xdigit, true);
      test(L"Xdigit", std::ctype_base::xdigit, true);
  
      test(L"dig", std::ctype_base::mask());
      test(L"", std::ctype_base::mask());
      test(L"digits", std::ctype_base::mask());
  
    return 0;
  }
  