1*4bdff4beSrobert //===----------------------------------------------------------------------===// 2*4bdff4beSrobert // 3*4bdff4beSrobert // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*4bdff4beSrobert // See https://llvm.org/LICENSE.txt for license information. 5*4bdff4beSrobert // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*4bdff4beSrobert // 7*4bdff4beSrobert //===----------------------------------------------------------------------===// 8*4bdff4beSrobert 9*4bdff4beSrobert #ifndef _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H 10*4bdff4beSrobert #define _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H 11*4bdff4beSrobert 12*4bdff4beSrobert #include <__concepts/boolean_testable.h> 13*4bdff4beSrobert #include <__concepts/common_reference_with.h> 14*4bdff4beSrobert #include <__config> 15*4bdff4beSrobert #include <__type_traits/common_reference.h> 16*4bdff4beSrobert #include <__type_traits/make_const_lvalue_ref.h> 17*4bdff4beSrobert 18*4bdff4beSrobert #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19*4bdff4beSrobert # pragma GCC system_header 20*4bdff4beSrobert #endif 21*4bdff4beSrobert 22*4bdff4beSrobert _LIBCPP_BEGIN_NAMESPACE_STD 23*4bdff4beSrobert 24*4bdff4beSrobert #if _LIBCPP_STD_VER > 17 25*4bdff4beSrobert 26*4bdff4beSrobert // [concept.equalitycomparable] 27*4bdff4beSrobert 28*4bdff4beSrobert template<class _Tp, class _Up> 29*4bdff4beSrobert concept __weakly_equality_comparable_with = requires(__make_const_lvalue_ref<_Tp> __t,__make_const_lvalue_ref<_Up> __u)30*4bdff4beSrobert requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) { 31*4bdff4beSrobert { __t == __u } -> __boolean_testable; 32*4bdff4beSrobert { __t != __u } -> __boolean_testable; 33*4bdff4beSrobert { __u == __t } -> __boolean_testable; 34*4bdff4beSrobert { __u != __t } -> __boolean_testable; 35*4bdff4beSrobert }; 36*4bdff4beSrobert 37*4bdff4beSrobert template<class _Tp> 38*4bdff4beSrobert concept equality_comparable = __weakly_equality_comparable_with<_Tp, _Tp>; 39*4bdff4beSrobert 40*4bdff4beSrobert template<class _Tp, class _Up> 41*4bdff4beSrobert concept equality_comparable_with = 42*4bdff4beSrobert equality_comparable<_Tp> && equality_comparable<_Up> && 43*4bdff4beSrobert common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> && 44*4bdff4beSrobert equality_comparable< 45*4bdff4beSrobert common_reference_t< 46*4bdff4beSrobert __make_const_lvalue_ref<_Tp>, 47*4bdff4beSrobert __make_const_lvalue_ref<_Up>>> && 48*4bdff4beSrobert __weakly_equality_comparable_with<_Tp, _Up>; 49*4bdff4beSrobert 50*4bdff4beSrobert #endif // _LIBCPP_STD_VER > 17 51*4bdff4beSrobert 52*4bdff4beSrobert _LIBCPP_END_NAMESPACE_STD 53*4bdff4beSrobert 54*4bdff4beSrobert #endif // _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H 55