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-exception 6 // 7 //===---------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___FWD_VARIANT_H 10 #define _LIBCPP___FWD_VARIANT_H 11 12 #include <__config> 13 #include <__cstddef/size_t.h> 14 15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 16 # pragma GCC system_header 17 #endif 18 19 _LIBCPP_BEGIN_NAMESPACE_STD 20 21 #if _LIBCPP_STD_VER >= 17 22 23 template <class... _Types> 24 class _LIBCPP_TEMPLATE_VIS variant; 25 26 template <class _Tp> 27 struct _LIBCPP_TEMPLATE_VIS variant_size; 28 29 template <class _Tp> 30 inline constexpr size_t variant_size_v = variant_size<_Tp>::value; 31 32 template <size_t _Ip, class _Tp> 33 struct _LIBCPP_TEMPLATE_VIS variant_alternative; 34 35 template <size_t _Ip, class _Tp> 36 using variant_alternative_t = typename variant_alternative<_Ip, _Tp>::type; 37 38 inline constexpr size_t variant_npos = static_cast<size_t>(-1); 39 40 template <size_t _Ip, class... _Types> 41 _LIBCPP_HIDE_FROM_ABI 42 _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr variant_alternative_t<_Ip, variant<_Types...>>& 43 get(variant<_Types...>&); 44 45 template <size_t _Ip, class... _Types> 46 _LIBCPP_HIDE_FROM_ABI 47 _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr variant_alternative_t<_Ip, variant<_Types...>>&& 48 get(variant<_Types...>&&); 49 50 template <size_t _Ip, class... _Types> 51 _LIBCPP_HIDE_FROM_ABI 52 _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const variant_alternative_t<_Ip, variant<_Types...>>& 53 get(const variant<_Types...>&); 54 55 template <size_t _Ip, class... _Types> 56 _LIBCPP_HIDE_FROM_ABI 57 _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const variant_alternative_t<_Ip, variant<_Types...>>&& 58 get(const variant<_Types...>&&); 59 60 template <class _Tp, class... _Types> 61 _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Tp& get(variant<_Types...>&); 62 63 template <class _Tp, class... _Types> 64 _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr _Tp&& get(variant<_Types...>&&); 65 66 template <class _Tp, class... _Types> 67 _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const _Tp& get(const variant<_Types...>&); 68 69 template <class _Tp, class... _Types> 70 _LIBCPP_HIDE_FROM_ABI _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS constexpr const _Tp&& 71 get(const variant<_Types...>&&); 72 73 #endif // _LIBCPP_STD_VER >= 17 74 75 _LIBCPP_END_NAMESPACE_STD 76 77 #endif // _LIBCPP___FWD_VARIANT_H 78