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 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
11
12 // constexpr iterator(iterator<!Const> i)
13 // requires Const && (convertible_to<iterator_t<Views>,
14 // iterator_t<maybe-const<Const, Views>>> && ...);
15
16 #include <ranges>
17
18 #include <cassert>
19 #include <tuple>
20
21 #include "../types.h"
22
23 using ConstIterIncompatibleView = BasicView<forward_iterator<int*>, forward_iterator<int*>,
24 random_access_iterator<const int*>, random_access_iterator<const int*>>;
25 static_assert(!std::convertible_to<std::ranges::iterator_t<ConstIterIncompatibleView>,
26 std::ranges::iterator_t<const ConstIterIncompatibleView>>);
27
test()28 constexpr bool test() {
29 int buffer[3] = {1, 2, 3};
30
31 {
32 std::ranges::zip_view v(NonSimpleCommon{buffer});
33 auto iter1 = v.begin();
34 std::ranges::iterator_t<const decltype(v)> iter2 = iter1;
35 assert(iter1 == iter2);
36
37 static_assert(!std::is_same_v<decltype(iter1), decltype(iter2)>);
38
39 // We cannot create a non-const iterator from a const iterator.
40 static_assert(!std::constructible_from<decltype(iter1), decltype(iter2)>);
41 }
42
43 {
44 // underlying non-const to const not convertible
45 std::ranges::zip_view v(ConstIterIncompatibleView{buffer});
46 auto iter1 = v.begin();
47 auto iter2 = std::as_const(v).begin();
48
49 static_assert(!std::is_same_v<decltype(iter1), decltype(iter2)>);
50
51 static_assert(!std::constructible_from<decltype(iter1), decltype(iter2)>);
52 static_assert(!std::constructible_from<decltype(iter2), decltype(iter1)>);
53 }
54
55 return true;
56 }
57
main(int,char **)58 int main(int, char**) {
59 test();
60 static_assert(test());
61
62 return 0;
63 }
64