| // -*- 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___FUNCTIONAL_PERFECT_FORWARD_H |
| #define _LIBCPP___FUNCTIONAL_PERFECT_FORWARD_H |
| |
| #include <__config> |
| #include <tuple> |
| #include <type_traits> |
| #include <utility> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if _LIBCPP_STD_VER > 14 |
| |
| template<class _Op, class _Tuple, |
| class _Idxs = typename __make_tuple_indices<tuple_size<_Tuple>::value>::type> |
| struct __perfect_forward_impl; |
| |
| template<class _Op, class... _Bound, size_t... _Idxs> |
| struct __perfect_forward_impl<_Op, __tuple_types<_Bound...>, __tuple_indices<_Idxs...>> |
| { |
| tuple<_Bound...> __bound_; |
| |
| template<class... _Args> |
| _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) & |
| noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...))) |
| -> decltype( _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...)) |
| {return _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...);} |
| |
| template<class... _Args> |
| _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) const& |
| noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...))) |
| -> decltype( _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...)) |
| {return _Op::__call(_VSTD::get<_Idxs>(__bound_)..., _VSTD::forward<_Args>(__args)...);} |
| |
| template<class... _Args> |
| _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) && |
| noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...))) |
| -> decltype( _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...)) |
| {return _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...);} |
| |
| template<class... _Args> |
| _LIBCPP_INLINE_VISIBILITY constexpr auto operator()(_Args&&... __args) const&& |
| noexcept(noexcept(_Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...))) |
| -> decltype( _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...)) |
| {return _Op::__call(_VSTD::get<_Idxs>(_VSTD::move(__bound_))..., |
| _VSTD::forward<_Args>(__args)...);} |
| |
| template<class _Fn = typename tuple_element<0, tuple<_Bound...>>::type, |
| class = _EnableIf<is_copy_constructible_v<_Fn>>> |
| constexpr __perfect_forward_impl(__perfect_forward_impl const& __other) |
| : __bound_(__other.__bound_) {} |
| |
| template<class _Fn = typename tuple_element<0, tuple<_Bound...>>::type, |
| class = _EnableIf<is_move_constructible_v<_Fn>>> |
| constexpr __perfect_forward_impl(__perfect_forward_impl && __other) |
| : __bound_(_VSTD::move(__other.__bound_)) {} |
| |
| template<class... _BoundArgs> |
| explicit constexpr __perfect_forward_impl(_BoundArgs&&... __bound) : |
| __bound_(_VSTD::forward<_BoundArgs>(__bound)...) { } |
| }; |
| |
| template<class _Op, class... _Args> |
| using __perfect_forward = |
| __perfect_forward_impl<_Op, __tuple_types<decay_t<_Args>...>>; |
| |
| #endif // _LIBCPP_STD_VER > 14 |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___FUNCTIONAL_PERFECT_FORWARD_H |