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