1050b064fSChristopher Di Bella // -*- C++ -*- 2050b064fSChristopher Di Bella //===----------------------------------------------------------------------===// 3050b064fSChristopher Di Bella // 4050b064fSChristopher Di Bella // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5050b064fSChristopher Di Bella // See https://llvm.org/LICENSE.txt for license information. 6050b064fSChristopher Di Bella // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7050b064fSChristopher Di Bella // 8050b064fSChristopher Di Bella //===----------------------------------------------------------------------===// 9050b064fSChristopher Di Bella 10050b064fSChristopher Di Bella #ifndef _LIBCPP___FUNCTIONAL_INVOKE_H 11050b064fSChristopher Di Bella #define _LIBCPP___FUNCTIONAL_INVOKE_H 12050b064fSChristopher Di Bella 13050b064fSChristopher Di Bella #include <__config> 14bea2ff65SMark de Wever #include <__type_traits/invoke.h> 15*09e3a360SLouis Dionne #include <__type_traits/is_void.h> 16050b064fSChristopher Di Bella #include <__utility/forward.h> 17050b064fSChristopher Di Bella 18050b064fSChristopher Di Bella #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19050b064fSChristopher Di Bella # pragma GCC system_header 20050b064fSChristopher Di Bella #endif 21050b064fSChristopher Di Bella 22050b064fSChristopher Di Bella _LIBCPP_BEGIN_NAMESPACE_STD 23050b064fSChristopher Di Bella 244f15267dSNikolas Klauser #if _LIBCPP_STD_VER >= 17 25050b064fSChristopher Di Bella 26050b064fSChristopher Di Bella template <class _Fn, class... _Args> 275146b57bSNikolas Klauser _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 invoke_result_t<_Fn, _Args...> 289783f28cSLouis Dionne invoke(_Fn&& __f, _Args&&... __args) noexcept(is_nothrow_invocable_v<_Fn, _Args...>) { 2977a00c0dSLouis Dionne return std::__invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...); 30050b064fSChristopher Di Bella } 31050b064fSChristopher Di Bella 324f15267dSNikolas Klauser #endif // _LIBCPP_STD_VER >= 17 33050b064fSChristopher Di Bella 3487cc95a9SLouis Dionne #if _LIBCPP_STD_VER >= 23 3587cc95a9SLouis Dionne template <class _Result, class _Fn, class... _Args> 3687cc95a9SLouis Dionne requires is_invocable_r_v<_Result, _Fn, _Args...> 3787cc95a9SLouis Dionne _LIBCPP_HIDE_FROM_ABI constexpr _Result 3887cc95a9SLouis Dionne invoke_r(_Fn&& __f, _Args&&... __args) noexcept(is_nothrow_invocable_r_v<_Result, _Fn, _Args...>) { 3987cc95a9SLouis Dionne if constexpr (is_void_v<_Result>) { 4087cc95a9SLouis Dionne static_cast<void>(std::invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...)); 4187cc95a9SLouis Dionne } else { 4287cc95a9SLouis Dionne // TODO: Use reference_converts_from_temporary_v once implemented 4387cc95a9SLouis Dionne // using _ImplicitInvokeResult = invoke_result_t<_Fn, _Args...>; 4487cc95a9SLouis Dionne // static_assert(!reference_converts_from_temporary_v<_Result, _ImplicitInvokeResult>, 4587cc95a9SLouis Dionne static_assert(true, 4687cc95a9SLouis Dionne "Returning from invoke_r would bind a temporary object to the reference return type, " 4787cc95a9SLouis Dionne "which would result in a dangling reference."); 4887cc95a9SLouis Dionne return std::invoke(std::forward<_Fn>(__f), std::forward<_Args>(__args)...); 4987cc95a9SLouis Dionne } 5087cc95a9SLouis Dionne } 5187cc95a9SLouis Dionne #endif 5287cc95a9SLouis Dionne 53050b064fSChristopher Di Bella _LIBCPP_END_NAMESPACE_STD 54050b064fSChristopher Di Bella 55050b064fSChristopher Di Bella #endif // _LIBCPP___FUNCTIONAL_INVOKE_H 56