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 // template<class E2> friend constexpr bool operator==(const expected& x, const unexpected<E2>& e);
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 struct Data {
22   int i;
23   constexpr Data(int ii) : i(ii) {}
24 
25   friend constexpr bool operator==(const Data& data, int ii) { return data.i == ii; }
26 };
27 
28 constexpr bool test() {
29   // x.has_value()
30   {
31     const std::expected<Data, Data> e1(std::in_place, 5);
32     std::unexpected<int> un2(10);
33     std::unexpected<int> un3(5);
34     assert(e1 != un2);
35     assert(e1 != un3);
36   }
37 
38   // !x.has_value()
39   {
40     const std::expected<Data, Data> e1(std::unexpect, 5);
41     std::unexpected<int> un2(10);
42     std::unexpected<int> un3(5);
43     assert(e1 != un2);
44     assert(e1 == un3);
45   }
46 
47   return true;
48 }
49 
50 int main(int, char**) {
51   test();
52   static_assert(test());
53   return 0;
54 }
55