| 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 iterator(iterator<!Const> i) |
| 12 | // requires Const && (convertible_to<iterator_t<Views>, |
| 13 | // iterator_t<maybe-const<Const, Views>>> && ...); |
| 14 | |
| 15 | #include <ranges> |
| 16 | |
| 17 | #include <cassert> |
| 18 | #include <tuple> |
| 19 | |
| 20 | #include "../types.h" |
| 21 | |
| 22 | using ConstIterIncompatibleView = BasicView<forward_iterator<int*>, forward_iterator<int*>, |
| 23 | random_access_iterator<const int*>, random_access_iterator<const int*>>; |
| 24 | static_assert(!std::convertible_to<std::ranges::iterator_t<ConstIterIncompatibleView>, |
| 25 | std::ranges::iterator_t<const ConstIterIncompatibleView>>); |
| 26 | |
| 27 | constexpr bool test() { |
| 28 | int buffer[3] = {1, 2, 3}; |
| 29 | |
| 30 | { |
| 31 | std::ranges::zip_view v(NonSimpleCommon{buffer}); |
| 32 | auto iter1 = v.begin(); |
| 33 | std::ranges::iterator_t<const decltype(v)> iter2 = iter1; |
| 34 | assert(iter1 == iter2); |
| 35 | |
| 36 | static_assert(!std::is_same_v<decltype(iter1), decltype(iter2)>); |
| 37 | |
| 38 | // We cannot create a non-const iterator from a const iterator. |
| 39 | static_assert(!std::constructible_from<decltype(iter1), decltype(iter2)>); |
| 40 | } |
| 41 | |
| 42 | { |
| 43 | // underlying non-const to const not convertible |
| 44 | std::ranges::zip_view v(ConstIterIncompatibleView{buffer}); |
| 45 | auto iter1 = v.begin(); |
| 46 | auto iter2 = std::as_const(v).begin(); |
| 47 | |
| 48 | static_assert(!std::is_same_v<decltype(iter1), decltype(iter2)>); |
| 49 | |
| 50 | static_assert(!std::constructible_from<decltype(iter1), decltype(iter2)>); |
| 51 | static_assert(!std::constructible_from<decltype(iter2), decltype(iter1)>); |
| 52 | } |
| 53 | |
| 54 | return true; |
| 55 | } |
| 56 | |
| 57 | int main(int, char**) { |
| 58 | test(); |
| 59 | static_assert(test()); |
| 60 | |
| 61 | return 0; |
| 62 | } |
| 63 | |