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-no-concepts
11 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
12 
13 // template<class R, class F>
14 //   transform_view(R&&, F) -> transform_view<views::all_t<R>, F>;
15 
16 #include <ranges>
17 #include <cassert>
18 #include <concepts>
19 
20 struct PlusOne {
21     int operator()(int x) const;
22 };
23 
24 struct View : std::ranges::view_base {
25   int *begin() const;
26   int *end() const;
27 };
28 
29 struct Range {
30   int *begin() const;
31   int *end() const;
32 };
33 
34 struct BorrowedRange {
35   int *begin() const;
36   int *end() const;
37 };
38 template<>
39 inline constexpr bool std::ranges::enable_borrowed_range<BorrowedRange> = true;
40 
41 void testCTAD() {
42     View v;
43     Range r;
44     BorrowedRange br;
45     PlusOne f;
46 
47     static_assert(std::same_as<
48         decltype(std::ranges::transform_view(v, f)),
49         std::ranges::transform_view<View, PlusOne>
50     >);
51     static_assert(std::same_as<
52         decltype(std::ranges::transform_view(std::move(v), f)),
53         std::ranges::transform_view<View, PlusOne>
54     >);
55     static_assert(std::same_as<
56         decltype(std::ranges::transform_view(r, f)),
57         std::ranges::transform_view<std::ranges::ref_view<Range>, PlusOne>
58     >);
59     static_assert(std::same_as<
60         decltype(std::ranges::transform_view(std::move(r), f)),
61         std::ranges::transform_view<std::ranges::owning_view<Range>, PlusOne>
62     >);
63     static_assert(std::same_as<
64         decltype(std::ranges::transform_view(br, f)),
65         std::ranges::transform_view<std::ranges::ref_view<BorrowedRange>, PlusOne>
66     >);
67     static_assert(std::same_as<
68         decltype(std::ranges::transform_view(std::move(br), f)),
69         std::ranges::transform_view<std::ranges::owning_view<BorrowedRange>, PlusOne>
70     >);
71 }
72