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 I2>
12 // struct in_in_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_in_result<A, A>, std::ranges::in_in_result<int, int>>);
25
26 struct B {
27 B(int);
28 };
29 // implicit conversion
30 static_assert(std::is_constructible_v<std::ranges::in_in_result<B, B>, std::ranges::in_in_result<int, int>>);
31 static_assert(std::is_constructible_v<std::ranges::in_in_result<B, B>, std::ranges::in_in_result<int, int>&>);
32 static_assert(std::is_constructible_v<std::ranges::in_in_result<B, B>, const std::ranges::in_in_result<int, int>>);
33 static_assert(std::is_constructible_v<std::ranges::in_in_result<B, B>, const std::ranges::in_in_result<int, int>&>);
34
35 struct C {
36 C(int&);
37 };
38 static_assert(!std::is_constructible_v<std::ranges::in_in_result<C, C>, std::ranges::in_in_result<int, int>&>);
39
40 // has to be convertible via const&
41 static_assert(std::is_convertible_v<std::ranges::in_in_result<int, int>&, std::ranges::in_in_result<long, long>>);
42 static_assert(std::is_convertible_v<const std::ranges::in_in_result<int, int>&, std::ranges::in_in_result<long, long>>);
43 static_assert(std::is_convertible_v<std::ranges::in_in_result<int, int>&&, std::ranges::in_in_result<long, long>>);
44 static_assert(std::is_convertible_v<const std::ranges::in_in_result<int, int>&&, std::ranges::in_in_result<long, long>>);
45
46 // should be move constructible
47 static_assert(std::is_move_constructible_v<std::ranges::in_in_result<MoveOnly, int>>);
48 static_assert(std::is_move_constructible_v<std::ranges::in_in_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_in_result<NotConvertible, int>, std::ranges::in_in_result<int, int>>);
53 static_assert(!std::is_convertible_v<std::ranges::in_in_result<int, NotConvertible>, std::ranges::in_in_result<int, int>>);
54
55 template <class T>
56 struct ConstructibleFrom {
ConstructibleFromConstructibleFrom57 constexpr ConstructibleFrom(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_in_result<int, double> res{10L, 0.};
65 assert(res.in1 == 10);
66 assert(res.in2 == 0.);
67 std::ranges::in_in_result<ConstructibleFrom<int>, ConstructibleFrom<double>> res2 = res;
68 assert(res2.in1.content == 10);
69 assert(res2.in2.content == 0.);
70 }
71
72 // Checks that conversions are possible when one of the types is move-only.
73 {
74 std::ranges::in_in_result<MoveOnly, int> res{MoveOnly{}, 0};
75 assert(res.in1.get() == 1);
76 [[maybe_unused]] auto res2 = static_cast<std::ranges::in_in_result<MoveOnly, int>>(std::move(res));
77 assert(res.in1.get() == 0);
78 }
79
80 // Checks that structured bindings get the correct values.
81 {
82 auto [in1, in2] = std::ranges::in_in_result<int, int>{1, 2};
83 assert(in1 == 1);
84 assert(in2 == 2);
85 }
86
87 return true;
88 }
89
main(int,char **)90 int main(int, char**) {
91 test();
92 static_assert(test());
93
94 return 0;
95 }
96