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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___FUNCTIONAL_NOT_FN_H11#define _LIBCPP___FUNCTIONAL_NOT_FN_H12 13#include <__config>14#include <__functional/invoke.h>15#include <__functional/perfect_forward.h>16#include <__type_traits/decay.h>17#include <__type_traits/enable_if.h>18#include <__type_traits/is_constructible.h>19#include <__type_traits/is_member_pointer.h>20#include <__type_traits/is_pointer.h>21#include <__utility/forward.h>22 23#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)24# pragma GCC system_header25#endif26 27_LIBCPP_BEGIN_NAMESPACE_STD28 29#if _LIBCPP_STD_VER >= 1730 31struct __not_fn_op {32 template <class... _Args>33 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto operator()(_Args&&... __args) const34 noexcept(noexcept(!std::invoke(std::forward<_Args>(__args)...)))35 -> decltype(!std::invoke(std::forward<_Args>(__args)...)) {36 return !std::invoke(std::forward<_Args>(__args)...);37 }38};39 40template <class _Fn>41struct __not_fn_t : __perfect_forward<__not_fn_op, _Fn> {42 using __perfect_forward<__not_fn_op, _Fn>::__perfect_forward;43};44 45template <class _Fn,46 class = enable_if_t< is_constructible_v<decay_t<_Fn>, _Fn> && is_move_constructible_v<decay_t<_Fn>> >>47_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 auto not_fn(_Fn&& __f) {48 return __not_fn_t<decay_t<_Fn>>(std::forward<_Fn>(__f));49}50 51#endif // _LIBCPP_STD_VER >= 1752 53#if _LIBCPP_STD_VER >= 2654 55template <auto _Fn>56struct __nttp_not_fn_t {57 template <class... _Args>58 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Args&&... __args) const59 noexcept(noexcept(!std::invoke(_Fn, std::forward<_Args>(__args)...)))60 -> decltype(!std::invoke(_Fn, std::forward<_Args>(__args)...)) {61 return !std::invoke(_Fn, std::forward<_Args>(__args)...);62 }63};64 65template <auto _Fn>66[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI constexpr auto not_fn() noexcept {67 if constexpr (using _Ty = decltype(_Fn); is_pointer_v<_Ty> || is_member_pointer_v<_Ty>)68 static_assert(_Fn != nullptr, "f cannot be equal to nullptr");69 return __nttp_not_fn_t<_Fn>();70}71 72#endif // _LIBCPP_STD_VER >= 2673 74_LIBCPP_END_NAMESPACE_STD75 76#endif // _LIBCPP___FUNCTIONAL_NOT_FN_H77