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-has-no-incomplete-ranges
11 
12 // constexpr take_view(V base, range_difference_t<V> count);
13 
14 #include <ranges>
15 #include <cassert>
16 
17 #include "test_macros.h"
18 #include "test_iterators.h"
19 #include "test_range.h"
20 #include "types.h"
21 
22 constexpr bool test() {
23   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
24 
25   {
26     std::ranges::take_view<CopyableView> tv(CopyableView{buffer}, 0);
27     assert(tv.base().ptr_ == buffer);
28     assert(tv.begin() == tv.end()); // Checking we have correct size.
29   }
30 
31   {
32     std::ranges::take_view<MoveOnlyView> tv(MoveOnlyView{buffer}, 1);
33     assert(std::move(tv).base().ptr_ == buffer);
34     assert(std::ranges::next(tv.begin(), 1) == tv.end()); // Checking we have correct size.
35   }
36 
37   {
38     const std::ranges::take_view<CopyableView> tv(CopyableView{buffer}, 2);
39     assert(tv.base().ptr_ == buffer);
40     assert(std::ranges::next(tv.begin(), 2) == tv.end()); // Checking we have correct size.
41   }
42 
43   return true;
44 }
45 
46 int main(int, char**) {
47   test();
48   static_assert(test());
49 
50   return 0;
51 }
52