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1//===---------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===---------------------------------------------------------------------===//8 9#ifndef _LIBCPP___FWD_VARIANT_H10#define _LIBCPP___FWD_VARIANT_H11 12#include <__config>13#include <__cstddef/size_t.h>14 15#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)16# pragma GCC system_header17#endif18 19_LIBCPP_BEGIN_NAMESPACE_STD20 21#if _LIBCPP_STD_VER >= 1722 23template <class... _Types>24class variant;25 26template <class _Tp>27struct variant_size;28 29template <class _Tp>30inline constexpr size_t variant_size_v = variant_size<_Tp>::value;31 32template <size_t _Ip, class _Tp>33struct variant_alternative;34 35template <size_t _Ip, class _Tp>36using variant_alternative_t = typename variant_alternative<_Ip, _Tp>::type;37 38inline constexpr size_t variant_npos = static_cast<size_t>(-1);39 40template <size_t _Ip, class... _Types>41_LIBCPP_HIDE_FROM_ABI constexpr variant_alternative_t<_Ip, variant<_Types...>>& get(variant<_Types...>&);42 43template <size_t _Ip, class... _Types>44_LIBCPP_HIDE_FROM_ABI constexpr variant_alternative_t<_Ip, variant<_Types...>>&& get(variant<_Types...>&&);45 46template <size_t _Ip, class... _Types>47_LIBCPP_HIDE_FROM_ABI constexpr const variant_alternative_t<_Ip, variant<_Types...>>& get(const variant<_Types...>&);48 49template <size_t _Ip, class... _Types>50_LIBCPP_HIDE_FROM_ABI constexpr const variant_alternative_t<_Ip, variant<_Types...>>&& get(const variant<_Types...>&&);51 52template <class _Tp, class... _Types>53_LIBCPP_HIDE_FROM_ABI constexpr _Tp& get(variant<_Types...>&);54 55template <class _Tp, class... _Types>56_LIBCPP_HIDE_FROM_ABI constexpr _Tp&& get(variant<_Types...>&&);57 58template <class _Tp, class... _Types>59_LIBCPP_HIDE_FROM_ABI constexpr const _Tp& get(const variant<_Types...>&);60 61template <class _Tp, class... _Types>62_LIBCPP_HIDE_FROM_ABI constexpr const _Tp&& get(const variant<_Types...>&&);63 64#endif // _LIBCPP_STD_VER >= 1765 66_LIBCPP_END_NAMESPACE_STD67 68#endif // _LIBCPP___FWD_VARIANT_H69