llvm-project/libcxx/include/__concepts/equality_comparable.h
Louis Dionne 5aa03b648b [libc++][NFC] Apply clang-format on large parts of the code base
This commit does a pass of clang-format over files in libc++ that
don't require major changes to conform to our style guide, or for
which we're not overly concerned about conflicting with in-flight
patches or hindering the git blame.

This roughly covers:
- benchmarks
- range algorithms
- concepts
- type traits

I did a manual verification of all the changes, and in particular I
applied clang-format on/off annotations in a few places where the
result was less readable after than before. This was not necessary
in a lot of places, however I did find that clang-format had pretty
bad taste when it comes to formatting concepts.

Differential Revision: https://reviews.llvm.org/D153140
2023-06-19 11:19:51 -04:00

57 lines
1.8 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H
#define _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H
#include <__concepts/boolean_testable.h>
#include <__concepts/common_reference_with.h>
#include <__config>
#include <__type_traits/common_reference.h>
#include <__type_traits/make_const_lvalue_ref.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER >= 20
// [concept.equalitycomparable]
template <class _Tp, class _Up>
concept __weakly_equality_comparable_with =
requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) {
{ __t == __u } -> __boolean_testable;
{ __t != __u } -> __boolean_testable;
{ __u == __t } -> __boolean_testable;
{ __u != __t } -> __boolean_testable;
};
template <class _Tp>
concept equality_comparable = __weakly_equality_comparable_with<_Tp, _Tp>;
// clang-format off
template <class _Tp, class _Up>
concept equality_comparable_with =
equality_comparable<_Tp> && equality_comparable<_Up> &&
common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> &&
equality_comparable<
common_reference_t<
__make_const_lvalue_ref<_Tp>,
__make_const_lvalue_ref<_Up>>> &&
__weakly_equality_comparable_with<_Tp, _Up>;
// clang-format on
#endif // _LIBCPP_STD_VER >= 20
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___CONCEPTS_EQUALITY_COMPARABLE_H