1349cc55cSDimitry Andric // -*- C++ -*- 2349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 3349cc55cSDimitry Andric // 4349cc55cSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5349cc55cSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 6349cc55cSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7349cc55cSDimitry Andric // 8349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 9349cc55cSDimitry Andric 10349cc55cSDimitry Andric #ifndef _LIBCPP___FUNCTIONAL_BIND_BACK_H 11349cc55cSDimitry Andric #define _LIBCPP___FUNCTIONAL_BIND_BACK_H 12349cc55cSDimitry Andric 13349cc55cSDimitry Andric #include <__config> 14349cc55cSDimitry Andric #include <__functional/invoke.h> 15349cc55cSDimitry Andric #include <__functional/perfect_forward.h> 16349cc55cSDimitry Andric #include <__utility/forward.h> 17349cc55cSDimitry Andric #include <__utility/integer_sequence.h> 18349cc55cSDimitry Andric #include <tuple> 19349cc55cSDimitry Andric #include <type_traits> 20349cc55cSDimitry Andric 21349cc55cSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 22349cc55cSDimitry Andric # pragma GCC system_header 23349cc55cSDimitry Andric #endif 24349cc55cSDimitry Andric 25349cc55cSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 26349cc55cSDimitry Andric 27349cc55cSDimitry Andric #if _LIBCPP_STD_VER > 17 28349cc55cSDimitry Andric 29349cc55cSDimitry Andric template <size_t _NBound, class = make_index_sequence<_NBound>> 30349cc55cSDimitry Andric struct __bind_back_op; 31349cc55cSDimitry Andric 32349cc55cSDimitry Andric template <size_t _NBound, size_t ..._Ip> 33349cc55cSDimitry Andric struct __bind_back_op<_NBound, index_sequence<_Ip...>> { 34*81ad6265SDimitry Andric template <class _Fn, class _BoundArgs, class... _Args> 35*81ad6265SDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Fn&& __f, _BoundArgs&& __bound_args, _Args&&... __args) const 36*81ad6265SDimitry Andric noexcept(noexcept(_VSTD::invoke(_VSTD::forward<_Fn>(__f), _VSTD::forward<_Args>(__args)..., _VSTD::get<_Ip>(_VSTD::forward<_BoundArgs>(__bound_args))...))) 37*81ad6265SDimitry Andric -> decltype( _VSTD::invoke(_VSTD::forward<_Fn>(__f), _VSTD::forward<_Args>(__args)..., _VSTD::get<_Ip>(_VSTD::forward<_BoundArgs>(__bound_args))...)) 38*81ad6265SDimitry Andric { return _VSTD::invoke(_VSTD::forward<_Fn>(__f), _VSTD::forward<_Args>(__args)..., _VSTD::get<_Ip>(_VSTD::forward<_BoundArgs>(__bound_args))...); } 39349cc55cSDimitry Andric }; 40349cc55cSDimitry Andric 41349cc55cSDimitry Andric template <class _Fn, class _BoundArgs> 42349cc55cSDimitry Andric struct __bind_back_t : __perfect_forward<__bind_back_op<tuple_size_v<_BoundArgs>>, _Fn, _BoundArgs> { 43349cc55cSDimitry Andric using __perfect_forward<__bind_back_op<tuple_size_v<_BoundArgs>>, _Fn, _BoundArgs>::__perfect_forward; 44349cc55cSDimitry Andric }; 45349cc55cSDimitry Andric 46349cc55cSDimitry Andric template <class _Fn, class ..._Args, class = enable_if_t< 47349cc55cSDimitry Andric _And< 48349cc55cSDimitry Andric is_constructible<decay_t<_Fn>, _Fn>, 49349cc55cSDimitry Andric is_move_constructible<decay_t<_Fn>>, 50349cc55cSDimitry Andric is_constructible<decay_t<_Args>, _Args>..., 51349cc55cSDimitry Andric is_move_constructible<decay_t<_Args>>... 52349cc55cSDimitry Andric >::value 53349cc55cSDimitry Andric >> 54349cc55cSDimitry Andric _LIBCPP_HIDE_FROM_ABI 55349cc55cSDimitry Andric constexpr auto __bind_back(_Fn&& __f, _Args&&... __args) 56349cc55cSDimitry Andric noexcept(noexcept(__bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(_VSTD::forward<_Fn>(__f), _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)))) 57349cc55cSDimitry Andric -> decltype( __bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(_VSTD::forward<_Fn>(__f), _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...))) 58349cc55cSDimitry Andric { return __bind_back_t<decay_t<_Fn>, tuple<decay_t<_Args>...>>(_VSTD::forward<_Fn>(__f), _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)); } 59349cc55cSDimitry Andric 60349cc55cSDimitry Andric #endif // _LIBCPP_STD_VER > 17 61349cc55cSDimitry Andric 62349cc55cSDimitry Andric _LIBCPP_END_NAMESPACE_STD 63349cc55cSDimitry Andric 64349cc55cSDimitry Andric #endif // _LIBCPP___FUNCTIONAL_BIND_BACK_H 65