| 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 | // <ranges> |
| 12 | |
| 13 | // constexpr Pred const& pred() const; |
| 14 | |
| 15 | #include <ranges> |
| 16 | |
| 17 | #include <cassert> |
| 18 | #include <concepts> |
| 19 | |
| 20 | struct Range : std::ranges::view_base { |
| 21 | int* begin() const; |
| 22 | int* end() const; |
| 23 | }; |
| 24 | |
| 25 | struct Pred { |
| 26 | bool operator()(int, int) const; |
| 27 | int value; |
| 28 | }; |
| 29 | |
| 30 | constexpr bool test() { |
| 31 | { |
| 32 | Pred pred{.value: 42}; |
| 33 | std::ranges::chunk_by_view<Range, Pred> const view(Range{}, pred); |
| 34 | std::same_as<Pred const&> decltype(auto) result = view.pred(); |
| 35 | assert(result.value == 42); |
| 36 | |
| 37 | // Make sure we're really holding a reference to something inside the view |
| 38 | assert(&result == &view.pred()); |
| 39 | } |
| 40 | |
| 41 | // Same, but calling on a non-const view |
| 42 | { |
| 43 | Pred pred{.value: 42}; |
| 44 | std::ranges::chunk_by_view<Range, Pred> view(Range{}, pred); |
| 45 | std::same_as<Pred const&> decltype(auto) result = view.pred(); |
| 46 | assert(result.value == 42); |
| 47 | |
| 48 | // Make sure we're really holding a reference to something inside the view |
| 49 | assert(&result == &view.pred()); |
| 50 | } |
| 51 | |
| 52 | return true; |
| 53 | } |
| 54 | |
| 55 | int main(int, char**) { |
| 56 | test(); |
| 57 | static_assert(test()); |
| 58 | |
| 59 | return 0; |
| 60 | } |
| 61 |