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 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20 10 11 // constexpr void operator*() const & noexcept; 12 13 #include <cassert> 14 #include <concepts> 15 #include <expected> 16 #include <type_traits> 17 #include <utility> 18 19 #include "test_macros.h" 20 21 // Test noexcept 22 template <class T> 23 concept DerefNoexcept = 24 requires(T t) { 25 { std::forward<T>(t).operator*() } noexcept; 26 }; 27 28 static_assert(!DerefNoexcept<int>); 29 30 static_assert(DerefNoexcept<std::expected<void, int>>); 31 32 constexpr bool test() { 33 const std::expected<void, int> e; 34 *e; 35 static_assert(std::is_same_v<decltype(*e), void>); 36 37 return true; 38 } 39 40 int main(int, char**) { 41 test(); 42 static_assert(test()); 43 return 0; 44 } 45