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 
11 // template<class T>
12 // concept borrowed_range;
13 
14 #include <ranges>
15 
16 struct NotRange {
17   int begin() const;
18   int end() const;
19 };
20 
21 struct Range {
22   int *begin();
23   int *end();
24 };
25 
26 struct ConstRange {
27   int *begin() const;
28   int *end() const;
29 };
30 
31 struct BorrowedRange {
32   int *begin() const;
33   int *end() const;
34 };
35 
36 template<>
37 inline constexpr bool std::ranges::enable_borrowed_range<BorrowedRange> = true;
38 
39 static_assert(!std::ranges::borrowed_range<NotRange>);
40 static_assert(!std::ranges::borrowed_range<NotRange&>);
41 static_assert(!std::ranges::borrowed_range<const NotRange>);
42 static_assert(!std::ranges::borrowed_range<const NotRange&>);
43 static_assert(!std::ranges::borrowed_range<NotRange&&>);
44 
45 static_assert(!std::ranges::borrowed_range<Range>);
46 static_assert( std::ranges::borrowed_range<Range&>);
47 static_assert(!std::ranges::borrowed_range<const Range>);
48 static_assert(!std::ranges::borrowed_range<const Range&>);
49 static_assert(!std::ranges::borrowed_range<Range&&>);
50 
51 static_assert(!std::ranges::borrowed_range<ConstRange>);
52 static_assert( std::ranges::borrowed_range<ConstRange&>);
53 static_assert(!std::ranges::borrowed_range<const ConstRange>);
54 static_assert( std::ranges::borrowed_range<const ConstRange&>);
55 static_assert(!std::ranges::borrowed_range<ConstRange&&>);
56 
57 static_assert( std::ranges::borrowed_range<BorrowedRange>);
58 static_assert( std::ranges::borrowed_range<BorrowedRange&>);
59 static_assert( std::ranges::borrowed_range<const BorrowedRange>);
60 static_assert( std::ranges::borrowed_range<const BorrowedRange&>);
61 static_assert( std::ranges::borrowed_range<BorrowedRange&&>);
62