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, c++20 10 11 // template <class I, class T> 12 // struct in_value_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_value_result<A, A>, std::ranges::in_value_result<int, int>>); 26 27 struct B { 28 B(int); 29 }; 30 // implicit conversion 31 static_assert(std::is_constructible_v<std::ranges::in_value_result<B, B>, std::ranges::in_value_result<int, int>>); 32 static_assert(std::is_constructible_v<std::ranges::in_value_result<B, B>, std::ranges::in_value_result<int, int>&>); 33 static_assert( 34 std::is_constructible_v<std::ranges::in_value_result<B, B>, const std::ranges::in_value_result<int, int>>); 35 static_assert( 36 std::is_constructible_v<std::ranges::in_value_result<B, B>, const std::ranges::in_value_result<int, int>&>); 37 38 struct C { 39 C(int&); 40 }; 41 static_assert(!std::is_constructible_v<std::ranges::in_value_result<C, C>, std::ranges::in_value_result<int, int>&>); 42 43 // has to be convertible via const& 44 static_assert(std::is_convertible_v<std::ranges::in_value_result<int, int>&, std::ranges::in_value_result<long, long>>); 45 static_assert( 46 std::is_convertible_v<const std::ranges::in_value_result<int, int>&, std::ranges::in_value_result<long, long>>); 47 static_assert( 48 std::is_convertible_v<std::ranges::in_value_result<int, int>&&, std::ranges::in_value_result<long, long>>); 49 static_assert( 50 std::is_convertible_v<const std::ranges::in_value_result<int, int>&&, std::ranges::in_value_result<long, long>>); 51 52 // should be move constructible 53 static_assert(std::is_move_constructible_v<std::ranges::in_value_result<MoveOnly, int>>); 54 static_assert(std::is_move_constructible_v<std::ranges::in_value_result<int, MoveOnly>>); 55 56 // should not copy constructible with move-only type 57 static_assert(!std::is_copy_constructible_v<std::ranges::in_value_result<MoveOnly, int>>); 58 static_assert(!std::is_copy_constructible_v<std::ranges::in_value_result<int, MoveOnly>>); 59 60 struct NotConvertible {}; 61 // conversions should not work if there is no conversion 62 static_assert( 63 !std::is_convertible_v<std::ranges::in_value_result<NotConvertible, int>, std::ranges::in_value_result<int, int>>); 64 static_assert( 65 !std::is_convertible_v<std::ranges::in_value_result<int, NotConvertible>, std::ranges::in_value_result<int, int>>); 66 67 template <class T> 68 struct ConvertibleFrom { 69 constexpr ConvertibleFrom(T c) : content{c} {} 70 T content; 71 }; 72 73 constexpr bool test() { 74 { 75 std::ranges::in_value_result<int, double> res{10, 0.}; 76 assert(res.in == 10); 77 assert(res.value == 0.); 78 std::ranges::in_value_result<ConvertibleFrom<int>, ConvertibleFrom<double>> res2 = res; 79 assert(res2.in.content == 10); 80 assert(res2.value.content == 0.); 81 } 82 { 83 std::ranges::in_value_result<MoveOnly, int> res{MoveOnly{}, 2}; 84 assert(res.in.get() == 1); 85 assert(res.value == 2); 86 auto res2 = static_cast<std::ranges::in_value_result<MoveOnly, int>>(std::move(res)); 87 assert(res.in.get() == 0); 88 assert(res2.in.get() == 1); 89 assert(res2.value == 2); 90 } 91 { 92 auto [in, value] = std::ranges::in_value_result<int, int>{1, 2}; 93 assert(in == 1); 94 assert(value == 2); 95 } 96 return true; 97 } 98 99 int main(int, char**) { 100 test(); 101 static_assert(test()); 102 103 return 0; 104 } 105