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
10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
11 
12 // constexpr outer-iterator(outer-iterator<!Const> i)
13 //   requires Const && convertible_to<iterator_t<View>, iterator_t<Base>>
14 
15 #include <ranges>
16 
17 #include <string_view>
18 #include <type_traits>
19 #include <utility>
20 #include "../types.h"
21 
22 // outer-iterator<Const = true>
23 
24 template <class Iter>
25 concept IsConstOuterIter = requires (Iter i) {
26   { *(*i).begin() } -> std::same_as<const char&>;
27 };
28 static_assert( IsConstOuterIter<OuterIterConst>);
29 
30 static_assert( std::convertible_to<
31     std::ranges::iterator_t<SplitViewDiff>, std::ranges::iterator_t<const SplitViewDiff>>);
32 
33 // outer-iterator<Const = false>
34 
35 template <class Iter>
36 concept IsNonConstOuterIter = requires (Iter i) {
37   { *(*i).begin() } -> std::same_as<char&>;
38 };
39 static_assert( IsNonConstOuterIter<OuterIterNonConst>);
40 
41 static_assert(!std::is_constructible_v<OuterIterNonConst, OuterIterConst>);
42 
43 constexpr bool test() {
44   [[maybe_unused]] OuterIterConst i(OuterIterNonConst{});
45 
46   return true;
47 }
48 
49 int main(int, char**) {
50   test();
51   static_assert(test());
52 
53   return 0;
54 }
55