176d0caaeSpatrick // -*- C++ -*- 276d0caaeSpatrick //===----------------------------------------------------------------------===// 376d0caaeSpatrick // 476d0caaeSpatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 576d0caaeSpatrick // See https://llvm.org/LICENSE.txt for license information. 676d0caaeSpatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 776d0caaeSpatrick // 876d0caaeSpatrick //===----------------------------------------------------------------------===// 976d0caaeSpatrick 1076d0caaeSpatrick #ifndef _LIBCPP___VARIANT_MONOSTATE_H 1176d0caaeSpatrick #define _LIBCPP___VARIANT_MONOSTATE_H 1276d0caaeSpatrick 13*4bdff4beSrobert #include <__compare/ordering.h> 1476d0caaeSpatrick #include <__config> 1576d0caaeSpatrick #include <__functional/hash.h> 1676d0caaeSpatrick #include <cstddef> 1776d0caaeSpatrick 1876d0caaeSpatrick #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 1976d0caaeSpatrick # pragma GCC system_header 2076d0caaeSpatrick #endif 2176d0caaeSpatrick 2276d0caaeSpatrick _LIBCPP_BEGIN_NAMESPACE_STD 2376d0caaeSpatrick 2476d0caaeSpatrick #if _LIBCPP_STD_VER > 14 2576d0caaeSpatrick 2676d0caaeSpatrick struct _LIBCPP_TEMPLATE_VIS monostate {}; 2776d0caaeSpatrick 28*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator==(monostate, monostate) noexcept { return true; } 2976d0caaeSpatrick 30*4bdff4beSrobert # if _LIBCPP_STD_VER > 17 3176d0caaeSpatrick 32*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr strong_ordering operator<=>(monostate, monostate) noexcept { 33*4bdff4beSrobert return strong_ordering::equal; 34*4bdff4beSrobert } 3576d0caaeSpatrick 36*4bdff4beSrobert # else // _LIBCPP_STD_VER > 17 3776d0caaeSpatrick 38*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator!=(monostate, monostate) noexcept { return false; } 3976d0caaeSpatrick 40*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator<(monostate, monostate) noexcept { return false; } 41*4bdff4beSrobert 42*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator>(monostate, monostate) noexcept { return false; } 43*4bdff4beSrobert 44*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator<=(monostate, monostate) noexcept { return true; } 45*4bdff4beSrobert 46*4bdff4beSrobert _LIBCPP_HIDE_FROM_ABI constexpr bool operator>=(monostate, monostate) noexcept { return true; } 47*4bdff4beSrobert 48*4bdff4beSrobert # endif // _LIBCPP_STD_VER > 17 4976d0caaeSpatrick 5076d0caaeSpatrick template <> 5176d0caaeSpatrick struct _LIBCPP_TEMPLATE_VIS hash<monostate> { 5276d0caaeSpatrick using argument_type = monostate; 5376d0caaeSpatrick using result_type = size_t; 5476d0caaeSpatrick 55*4bdff4beSrobert inline _LIBCPP_HIDE_FROM_ABI result_type operator()(const argument_type&) const _NOEXCEPT { 5676d0caaeSpatrick return 66740831; // return a fundamentally attractive random value. 5776d0caaeSpatrick } 5876d0caaeSpatrick }; 5976d0caaeSpatrick 6076d0caaeSpatrick #endif // _LIBCPP_STD_VER > 14 6176d0caaeSpatrick 6276d0caaeSpatrick _LIBCPP_END_NAMESPACE_STD 6376d0caaeSpatrick 6476d0caaeSpatrick #endif // _LIBCPP___VARIANT_MONOSTATE_H 65