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//===----------------------------------------------------------------------===//
//
// 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___TYPE_TRAITS_CONDITIONAL_H
#define _LIBCPP___TYPE_TRAITS_CONDITIONAL_H
#include <__config>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
template <bool>
struct _IfImpl;
template <>
struct _IfImpl<true> {
template <class _IfRes, class _ElseRes>
using _Select _LIBCPP_NODEBUG = _IfRes;
};
template <>
struct _IfImpl<false> {
template <class _IfRes, class _ElseRes>
using _Select _LIBCPP_NODEBUG = _ElseRes;
};
template <bool _Cond, class _IfRes, class _ElseRes>
using _If _LIBCPP_NODEBUG = typename _IfImpl<_Cond>::template _Select<_IfRes, _ElseRes>;
template <bool _Bp, class _If, class _Then>
struct _LIBCPP_NO_SPECIALIZATIONS conditional {
using type _LIBCPP_NODEBUG = _If;
};
_LIBCPP_DIAGNOSTIC_PUSH
#if __has_warning("-Winvalid-specialization")
_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Winvalid-specialization")
#endif
template <class _If, class _Then>
struct conditional<false, _If, _Then> {
using type _LIBCPP_NODEBUG = _Then;
};
_LIBCPP_DIAGNOSTIC_POP
#if _LIBCPP_STD_VER >= 14
template <bool _Bp, class _IfRes, class _ElseRes>
using conditional_t _LIBCPP_NODEBUG = typename conditional<_Bp, _IfRes, _ElseRes>::type;
#endif
// Helper so we can use "conditional_t" in all language versions.
template <bool _Bp, class _If, class _Then>
using __conditional_t _LIBCPP_NODEBUG = typename conditional<_Bp, _If, _Then>::type;
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___TYPE_TRAITS_CONDITIONAL_H
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