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 I1, class O1>
12 // struct in_out_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_out_result<A, A>, std::ranges::in_out_result<int, int>>);
25
26 struct B {
27 B(int);
28 };
29 // implicit conversion
30 static_assert(std::is_constructible_v<std::ranges::in_out_result<B, B>, std::ranges::in_out_result<int, int>>);
31 static_assert(std::is_constructible_v<std::ranges::in_out_result<B, B>, std::ranges::in_out_result<int, int>&>);
32 static_assert(std::is_constructible_v<std::ranges::in_out_result<B, B>, const std::ranges::in_out_result<int, int>>);
33 static_assert(std::is_constructible_v<std::ranges::in_out_result<B, B>, const std::ranges::in_out_result<int, int>&>);
34
35 struct C {
36 C(int&);
37 };
38 static_assert(!std::is_constructible_v<std::ranges::in_out_result<C, C>, std::ranges::in_out_result<int, int>&>);
39
40 // has to be convertible via const&
41 static_assert(std::is_convertible_v<std::ranges::in_out_result<int, int>&, std::ranges::in_out_result<long, long>>);
42 static_assert(std::is_convertible_v<const std::ranges::in_out_result<int, int>&, std::ranges::in_out_result<long, long>>);
43 static_assert(std::is_convertible_v<std::ranges::in_out_result<int, int>&&, std::ranges::in_out_result<long, long>>);
44 static_assert(std::is_convertible_v<const std::ranges::in_out_result<int, int>&&, std::ranges::in_out_result<long, long>>);
45
46 // should be move constructible
47 static_assert(std::is_move_constructible_v<std::ranges::in_out_result<MoveOnly, int>>);
48 static_assert(std::is_move_constructible_v<std::ranges::in_out_result<int, MoveOnly>>);
49
50 struct NotConvertible {};
51 // conversions should not work if there is no conversion
52 static_assert(!std::is_convertible_v<std::ranges::in_out_result<NotConvertible, int>, std::ranges::in_out_result<int, NotConvertible>>);
53 static_assert(!std::is_convertible_v<std::ranges::in_out_result<int, NotConvertible>, std::ranges::in_out_result<NotConvertible, int>>);
54
55 template <class T>
56 struct ConvertibleFrom {
ConvertibleFromConvertibleFrom57 constexpr ConvertibleFrom(T c) : content{c} {}
58 T content;
59 };
60
test()61 constexpr bool test() {
62 // Checks that conversion operations are correct.
63 {
64 std::ranges::in_out_result<double, int> res{10, 1};
65 assert(res.in == 10);
66 assert(res.out == 1);
67 std::ranges::in_out_result<ConvertibleFrom<double>, ConvertibleFrom<int>> res2 = res;
68 assert(res2.in.content == 10);
69 assert(res2.out.content == 1);
70 }
71
72 // Checks that conversions are possible when one of the types is move-only.
73 {
74 std::ranges::in_out_result<MoveOnly, int> res{MoveOnly{}, 10};
75 assert(res.in.get() == 1);
76 assert(res.out == 10);
77 auto res2 = std::move(res);
78 assert(res.in.get() == 0);
79 assert(res.out == 10);
80 assert(res2.in.get() == 1);
81 assert(res2.out == 10);
82 }
83
84 // Checks that structured bindings get the correct values.
85 {
86 auto [min, max] = std::ranges::in_out_result<int, int>{1, 2};
87 assert(min == 1);
88 assert(max == 2);
89 }
90
91 return true;
92 }
93
main(int,char **)94 int main(int, char**) {
95 test();
96 static_assert(test());
97
98 return 0;
99 }
100