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 R>
12 // explicit join_view(R&&) -> join_view<views::all_t<R>>;
13
14 #include <ranges>
15 #include <utility>
16
17 struct Child {
18 int *begin() const;
19 int *end() const;
20 };
21
22 struct View : std::ranges::view_base {
23 Child *begin() const;
24 Child *end() const;
25 };
26
27 struct Range {
28 Child *begin() const;
29 Child *end() const;
30 };
31
32 struct BorrowedRange {
33 Child *begin() const;
34 Child *end() const;
35 };
36 template<>
37 inline constexpr bool std::ranges::enable_borrowed_range<BorrowedRange> = true;
38
39 struct NestedChildren : std::ranges::view_base {
40 View* begin() const;
41 View* end() const;
42 };
43
testCTAD()44 void testCTAD() {
45 View v;
46 Range r;
47 BorrowedRange br;
48
49 static_assert(std::same_as<
50 decltype(std::ranges::join_view(v)),
51 std::ranges::join_view<View>
52 >);
53 static_assert(std::same_as<
54 decltype(std::ranges::join_view(std::move(v))),
55 std::ranges::join_view<View>
56 >);
57 static_assert(std::same_as<
58 decltype(std::ranges::join_view(r)),
59 std::ranges::join_view<std::ranges::ref_view<Range>>
60 >);
61 static_assert(std::same_as<
62 decltype(std::ranges::join_view(std::move(r))),
63 std::ranges::join_view<std::ranges::owning_view<Range>>
64 >);
65 static_assert(std::same_as<
66 decltype(std::ranges::join_view(br)),
67 std::ranges::join_view<std::ranges::ref_view<BorrowedRange>>
68 >);
69 static_assert(std::same_as<
70 decltype(std::ranges::join_view(std::move(br))),
71 std::ranges::join_view<std::ranges::owning_view<BorrowedRange>>
72 >);
73
74 NestedChildren n;
75 std::ranges::join_view jv(n);
76
77 // CTAD generated from the copy constructor instead of joining the join_view
78 static_assert(std::same_as< decltype(std::ranges::join_view(jv)), decltype(jv) >);
79
80 // CTAD generated from the move constructor instead of joining the join_view
81 static_assert(std::same_as< decltype(std::ranges::join_view(std::move(jv))), decltype(jv) >);
82 }
83