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 // <functional> 10 // 11 // template <class T> 12 // struct unwrap_ref_decay; 13 // 14 // template <class T> 15 // using unwrap_ref_decay_t = typename unwrap_ref_decay<T>::type; 16 17 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17 18 19 #include <functional> 20 #include <type_traits> 21 22 #include "test_macros.h" 23 24 25 template <typename T, typename Result> 26 void check() { 27 static_assert(std::is_same_v<typename std::unwrap_ref_decay<T>::type, Result>); 28 static_assert(std::is_same_v<typename std::unwrap_ref_decay<T>::type, std::unwrap_ref_decay_t<T>>); 29 } 30 31 struct T { }; 32 33 int main(int, char**) { 34 check<T, T>(); 35 check<T&, T>(); 36 check<T const, T>(); 37 check<T const&, T>(); 38 check<T*, T*>(); 39 check<T const*, T const*>(); 40 check<T[3], T*>(); 41 check<T const [3], T const*>(); 42 check<T (), T (*)()>(); 43 check<T (int) const, T (int) const>(); 44 check<T (int) &, T (int) &>(); 45 check<T (int) &&, T (int) &&>(); 46 47 check<std::reference_wrapper<T>, T&>(); 48 check<std::reference_wrapper<T>&, T&>(); 49 check<std::reference_wrapper<T const>, T const&>(); 50 check<std::reference_wrapper<T const>&, T const&>(); 51 check<std::reference_wrapper<T*>, T*&>(); 52 check<std::reference_wrapper<T*>&, T*&>(); 53 check<std::reference_wrapper<T const*>, T const*&>(); 54 check<std::reference_wrapper<T const*>&, T const*&>(); 55 check<std::reference_wrapper<T[3]>, T (&)[3]>(); 56 check<std::reference_wrapper<T[3]>&, T (&)[3]>(); 57 check<std::reference_wrapper<T ()>, T (&)()>(); 58 check<std::reference_wrapper<T ()>&, T (&)()>(); 59 60 return 0; 61 } 62