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<viewable_range R>
14 // using all_t = decltype(views::all(declval<R>()));
15 
16 #include <ranges>
17 
18 #include "test_iterators.h"
19 #include "test_range.h"
20 
21 struct View : test_range<cpp20_input_iterator>, std::ranges::view_base { };
22 struct Range : test_range<cpp20_input_iterator> { };
23 struct BorrowableRange : test_range<forward_iterator> { };
24 template<>
25 inline constexpr bool std::ranges::enable_borrowed_range<BorrowableRange> = true;
26 
27 // When T is a view, returns decay-copy(T)
28 ASSERT_SAME_TYPE(std::views::all_t<View>, View);
29 ASSERT_SAME_TYPE(std::views::all_t<View&>, View);
30 ASSERT_SAME_TYPE(std::views::all_t<View const>, View);
31 ASSERT_SAME_TYPE(std::views::all_t<View const&>, View);
32 
33 // Otherwise, when T is a reference to a range, returns ref_view<T>
34 ASSERT_SAME_TYPE(std::views::all_t<Range&>, std::ranges::ref_view<Range>);
35 ASSERT_SAME_TYPE(std::views::all_t<Range const&>, std::ranges::ref_view<Range const>);
36 ASSERT_SAME_TYPE(std::views::all_t<BorrowableRange&>, std::ranges::ref_view<BorrowableRange>);
37 ASSERT_SAME_TYPE(std::views::all_t<BorrowableRange const&>, std::ranges::ref_view<BorrowableRange const>);
38 
39 // Otherwise, returns subrange<iterator_t<T>, sentinel_t<R>>
40 ASSERT_SAME_TYPE(std::views::all_t<BorrowableRange>, std::ranges::subrange<forward_iterator<int*>, sentinel>);
41 ASSERT_SAME_TYPE(std::views::all_t<BorrowableRange const>, std::ranges::subrange<forward_iterator<int const*>, sentinel>);
42