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
10
11 // template <class I>
12 // struct in_found_result;
13
14 #include <algorithm>
15 #include <cassert>
16 #include <type_traits>
17
18 #include "MoveOnly.h"
19
20 struct A {
21 explicit A(int);
22 };
23 // no implicit conversion
24 static_assert(!std::is_constructible_v<std::ranges::in_found_result<A>, std::ranges::in_found_result<int>>);
25
26 struct B {
27 B(const int&);
28 B(int&&);
29 };
30 // implicit conversion
31 static_assert(std::is_constructible_v<std::ranges::in_found_result<B>, std::ranges::in_found_result<int>>);
32 static_assert(std::is_constructible_v<std::ranges::in_found_result<B>, std::ranges::in_found_result<int>&>);
33 static_assert(std::is_constructible_v<std::ranges::in_found_result<B>, const std::ranges::in_found_result<int>>);
34 static_assert(std::is_constructible_v<std::ranges::in_found_result<B>, const std::ranges::in_found_result<int>&>);
35
36 struct C {
37 C(int&);
38 };
39 static_assert(!std::is_constructible_v<std::ranges::in_found_result<C>, std::ranges::in_found_result<int>&>);
40
41 // has to be convertible via const&
42 static_assert(std::is_convertible_v<std::ranges::in_found_result<int>&, std::ranges::in_found_result<long>>);
43 static_assert(std::is_convertible_v<const std::ranges::in_found_result<int>&, std::ranges::in_found_result<long>>);
44 static_assert(std::is_convertible_v<std::ranges::in_found_result<int>&&, std::ranges::in_found_result<long>>);
45 static_assert(std::is_convertible_v<const std::ranges::in_found_result<int>&&, std::ranges::in_found_result<long>>);
46
47 // should be move constructible
48 static_assert(std::is_move_constructible_v<std::ranges::in_found_result<MoveOnly>>);
49
50 // should not be copy constructible
51 static_assert(!std::is_copy_constructible_v<std::ranges::in_found_result<MoveOnly>>);
52
53 struct NotConvertible {};
54 // conversions should not work if there is no conversion
55 static_assert(!std::is_convertible_v<std::ranges::in_found_result<NotConvertible>, std::ranges::in_found_result<int>>);
56
57 static_assert(std::is_same_v<decltype(std::ranges::in_found_result<int>::in), int>);
58 static_assert(std::is_same_v<decltype(std::ranges::in_found_result<int>::found), bool>);
59
60 template <class T>
61 struct ConvertibleFrom {
ConvertibleFromConvertibleFrom62 constexpr ConvertibleFrom(T c) : content{c} {}
63 T content;
64 };
65
test()66 constexpr bool test() {
67 // Checks that conversion operations are correct.
68 {
69 std::ranges::in_found_result<double> res{10, true};
70 assert(res.in == 10);
71 assert(res.found == true);
72 std::ranges::in_found_result<ConvertibleFrom<int>> res2 = res;
73 assert(res2.in.content == 10);
74 assert(res2.found == true);
75 }
76
77 // Checks that conversions are possible when one of the types is move-only.
78 {
79 std::ranges::in_found_result<MoveOnly> res{MoveOnly{}, false};
80 assert(res.in.get() == 1);
81 assert(!res.found);
82 auto res2 = std::move(res);
83 assert(res2.in.get() == 1);
84 assert(!res2.found);
85 assert(res.in.get() == 0);
86 assert(!res.found);
87 }
88
89 // Checks that structured bindings get the correct values.
90 {
91 auto [in, found] = std::ranges::in_found_result<int>{2, false};
92 assert(in == 2);
93 assert(!found);
94 }
95 return true;
96 }
97
main(int,char **)98 int main(int, char**) {
99 test();
100 static_assert(test());
101
102 return 0;
103 }
104