xref: /llvm-project/libcxx/test/std/ranges/range.adaptors/range.take/ctad.compile.pass.cpp (revision b8cb1dc9ea87faa8e8e9ab7a31710a8c0bb8b084)
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 //   take_view(R&&, range_difference_t<R>) -> take_view<views::all_t<R>>;
13 
14 #include <cassert>
15 #include <concepts>
16 #include <ranges>
17 #include <utility>
18 
19 struct View : std::ranges::view_base {
20   int *begin() const;
21   int *end() const;
22 };
23 
24 struct Range {
25   int *begin() const;
26   int *end() const;
27 };
28 
29 struct BorrowedRange {
30   int *begin() const;
31   int *end() const;
32 };
33 template<>
34 inline constexpr bool std::ranges::enable_borrowed_range<BorrowedRange> = true;
35 
testCTAD()36 void testCTAD() {
37     View v;
38     Range r;
39     BorrowedRange br;
40 
41     static_assert(std::same_as<
42         decltype(std::ranges::take_view(v, 0)),
43         std::ranges::take_view<View>
44     >);
45     static_assert(std::same_as<
46         decltype(std::ranges::take_view(std::move(v), 0)),
47         std::ranges::take_view<View>
48     >);
49     static_assert(std::same_as<
50         decltype(std::ranges::take_view(r, 0)),
51         std::ranges::take_view<std::ranges::ref_view<Range>>
52     >);
53     static_assert(std::same_as<
54         decltype(std::ranges::take_view(std::move(r), 0)),
55         std::ranges::take_view<std::ranges::owning_view<Range>>
56     >);
57     static_assert(std::same_as<
58         decltype(std::ranges::take_view(br, 0)),
59         std::ranges::take_view<std::ranges::ref_view<BorrowedRange>>
60     >);
61     static_assert(std::same_as<
62         decltype(std::ranges::take_view(std::move(br), 0)),
63         std::ranges::take_view<std::ranges::owning_view<BorrowedRange>>
64     >);
65 }
66