text: //===----------------------------------------------------------------------===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is dual licensed under the MIT and the University of Illinois Open
  // Source Licenses. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  
  // <functional>
  
  // bit_not
  
  #include <functional>
  #include <type_traits>
  #include <cassert>
  
  int main()
  {
  #if _LIBCPP_STD_VER > 11
      typedef std::bit_not<int> F;
      const F f = F();
      static_assert((std::is_base_of<std::unary_function<int, int>, F>::value), "");
      assert((f(0xEA95) & 0xFFFF ) == 0x156A);
      assert((f(0x58D3) & 0xFFFF ) == 0xA72C);
      assert((f(0)      & 0xFFFF ) == 0xFFFF);
      assert((f(0xFFFF) & 0xFFFF ) == 0);
  
      typedef std::bit_not<> F2;
      const F2 f2 = F2();
      assert((f2(0xEA95)  & 0xFFFF ) == 0x156A);
      assert((f2(0xEA95L) & 0xFFFF ) == 0x156A);
      assert((f2(0x58D3)  & 0xFFFF ) == 0xA72C);
      assert((f2(0x58D3L) & 0xFFFF ) == 0xA72C);
      assert((f2(0)       & 0xFFFF ) == 0xFFFF);
      assert((f2(0L)      & 0xFFFF ) == 0xFFFF);
      assert((f2(0xFFFF)  & 0xFFFF ) == 0);
      assert((f2(0xFFFFL)  & 0xFFFF ) == 0);
  
      constexpr int foo = std::bit_not<int> () (0xEA95) & 0xFFFF;
      static_assert ( foo == 0x156A, "" );
  
      constexpr int bar = std::bit_not<> () (0xEA95) & 0xFFFF;
      static_assert ( bar == 0x156A, "" );
  #endif
  }
  