| 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 | // constexpr V base() const & requires copy_constructible<V> { return base_; } |
| 12 | // constexpr V base() && { return std::move(base_); } |
| 13 | |
| 14 | #include <cassert> |
| 15 | #include <ranges> |
| 16 | #include <utility> |
| 17 | |
| 18 | #include "MoveOnly.h" |
| 19 | |
| 20 | struct SimpleView : std::ranges::view_base { |
| 21 | int i; |
| 22 | int* begin() const; |
| 23 | int* end() const; |
| 24 | }; |
| 25 | |
| 26 | struct MoveOnlyView : SimpleView { |
| 27 | MoveOnly m; |
| 28 | }; |
| 29 | |
| 30 | template <class T> |
| 31 | concept HasBase = requires(T&& t) { std::forward<T>(t).base(); }; |
| 32 | |
| 33 | static_assert(HasBase<std::ranges::as_rvalue_view<SimpleView> const&>); |
| 34 | static_assert(HasBase<std::ranges::as_rvalue_view<SimpleView>&&>); |
| 35 | |
| 36 | static_assert(!HasBase<std::ranges::as_rvalue_view<MoveOnlyView> const&>); |
| 37 | static_assert(HasBase<std::ranges::as_rvalue_view<MoveOnlyView>&&>); |
| 38 | |
| 39 | constexpr bool test() { |
| 40 | { // const & |
| 41 | const std::ranges::as_rvalue_view<SimpleView> view(SimpleView{{}, 5}); |
| 42 | std::same_as<SimpleView> decltype(auto) v = view.base(); |
| 43 | assert(v.i == 5); |
| 44 | } |
| 45 | |
| 46 | { // & |
| 47 | std::ranges::as_rvalue_view<SimpleView> view(SimpleView{{}, 5}); |
| 48 | std::same_as<SimpleView> decltype(auto) v = view.base(); |
| 49 | assert(v.i == 5); |
| 50 | } |
| 51 | |
| 52 | { // && |
| 53 | std::ranges::as_rvalue_view<SimpleView> view(SimpleView{{}, 5}); |
| 54 | std::same_as<SimpleView> decltype(auto) v = std::move(view).base(); |
| 55 | assert(v.i == 5); |
| 56 | } |
| 57 | |
| 58 | { // const && |
| 59 | const std::ranges::as_rvalue_view<SimpleView> view(SimpleView{{}, 5}); |
| 60 | std::same_as<SimpleView> decltype(auto) v = std::move(view).base(); |
| 61 | assert(v.i == 5); |
| 62 | } |
| 63 | |
| 64 | { // move only |
| 65 | std::ranges::as_rvalue_view<MoveOnlyView> view(MoveOnlyView{{}, 5}); |
| 66 | std::same_as<MoveOnlyView> decltype(auto) v = std::move(view).base(); |
| 67 | assert(v.m.get() == 5); |
| 68 | } |
| 69 | |
| 70 | return true; |
| 71 | } |
| 72 | |
| 73 | int main(int, char**) { |
| 74 | test(); |
| 75 | static_assert(test()); |
| 76 | |
| 77 | return 0; |
| 78 | } |
| 79 | |