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
21struct A {
22 explicit A(int);
23};
24// no implicit conversion
25static_assert(!std::is_constructible_v<std::ranges::in_fun_result<A, A>, std::ranges::in_fun_result<int, int>>);
26
27struct B {
28 B(int);
29};
30// implicit conversion
31static_assert(std::is_constructible_v<std::ranges::in_fun_result<B, B>, std::ranges::in_fun_result<int, int>>);
32static_assert(std::is_constructible_v<std::ranges::in_fun_result<B, B>, std::ranges::in_fun_result<int, int>&>);
33static_assert(std::is_constructible_v<std::ranges::in_fun_result<B, B>, const std::ranges::in_fun_result<int, int>>);
34static_assert(std::is_constructible_v<std::ranges::in_fun_result<B, B>, const std::ranges::in_fun_result<int, int>&>);
35
36struct C {
37 C(int&);
38};
39static_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&
42static_assert(std::is_convertible_v<std::ranges::in_fun_result<int, int>&, std::ranges::in_fun_result<long, long>>);
43static_assert(std::is_convertible_v<const std::ranges::in_fun_result<int, int>&, std::ranges::in_fun_result<long, long>>);
44static_assert(std::is_convertible_v<std::ranges::in_fun_result<int, int>&&, std::ranges::in_fun_result<long, long>>);
45static_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
48static_assert(std::is_move_constructible_v<std::ranges::in_fun_result<MoveOnly, int>>);
49static_assert(std::is_move_constructible_v<std::ranges::in_fun_result<int, MoveOnly>>);
50
51// should not be copy constructible with move-only type
52static_assert(!std::is_copy_constructible_v<std::ranges::in_fun_result<MoveOnly, int>>);
53static_assert(!std::is_copy_constructible_v<std::ranges::in_fun_result<int, MoveOnly>>);
54
55struct NotConvertible {};
56// conversions should not work if there is no conversion
57static_assert(!std::is_convertible_v<std::ranges::in_fun_result<NotConvertible, int>, std::ranges::in_fun_result<int, int>>);
58static_assert(!std::is_convertible_v<std::ranges::in_fun_result<int, NotConvertible>, std::ranges::in_fun_result<int, int>>);
59
60template <class T>
61struct ConvertibleFrom {
62 constexpr ConvertibleFrom(T c) : content{c} {}
63 T content;
64};
65
66constexpr 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
97int main(int, char**) {
98 test();
99 static_assert(test());
100
101 return 0;
102}
103

source code of libcxx/test/std/algorithms/algorithms.results/in_fun_result.pass.cpp