chromium/third_party/libc++/src/include/__memory/compressed_pair.h

// -*- 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___MEMORY_COMPRESSED_PAIR_H
#define _LIBCPP___MEMORY_COMPRESSED_PAIR_H

#include <__config>
#include <__fwd/tuple.h>
#include <__tuple/tuple_indices.h>
#include <__type_traits/decay.h>
#include <__type_traits/dependent_type.h>
#include <__type_traits/enable_if.h>
#include <__type_traits/is_constructible.h>
#include <__type_traits/is_empty.h>
#include <__type_traits/is_final.h>
#include <__type_traits/is_same.h>
#include <__type_traits/is_swappable.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <__utility/piecewise_construct.h>
#include <cstddef>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

_LIBCPP_BEGIN_NAMESPACE_STD

// Tag used to default initialize one or both of the pair's elements.
struct __default_init_tag { … };
struct __value_init_tag { … };

template <class _Tp, int _Idx, bool _CanBeEmptyBase = is_empty<_Tp>::value && !__libcpp_is_final<_Tp>::value>
struct __compressed_pair_elem { … };

__compressed_pair_elem<_Tp, _Idx, true>;

template <class _T1, class _T2>
class __compressed_pair : private __compressed_pair_elem<_T1, 0>, private __compressed_pair_elem<_T2, 1> { … };

template <class _T1, class _T2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
    _NOEXCEPT_(__is_nothrow_swappable_v<_T1>&& __is_nothrow_swappable_v<_T2>) { … }

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS

#endif // _LIBCPP___MEMORY_COMPRESSED_PAIR_H