xref: /llvm-project/libcxx/test/std/ranges/range.adaptors/range.drop/ctor.view.pass.cpp (revision 40aaa272f145e633b29d5e70a4590cc425801f7e)
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 // constexpr drop_view(V base, range_difference_t<V> count);  // explicit since C++23
12 
13 #include <ranges>
14 
15 #include "test_convertible.h"
16 #include "test_macros.h"
17 #include "types.h"
18 
19 // SFINAE tests.
20 
21 #if TEST_STD_VER >= 23
22 
23 static_assert(!test_convertible<std::ranges::drop_view<View>, View, std::ranges::range_difference_t<View>>(),
24               "This constructor must be explicit");
25 
26 #else
27 
28 static_assert(test_convertible<std::ranges::drop_view<View>, View, std::ranges::range_difference_t<View>>(),
29               "This constructor must not be explicit");
30 
31 #endif // TEST_STD_VER >= 23
32 
test()33 constexpr bool test() {
34   std::ranges::drop_view dropView1(MoveOnlyView(), 4);
35   assert(dropView1.size() == 4);
36   assert(dropView1.begin() == globalBuff + 4);
37 
38   std::ranges::drop_view dropView2(ForwardView(), 4);
39   assert(base(dropView2.begin()) == globalBuff + 4);
40 
41   return true;
42 }
43 
main(int,char **)44 int main(int, char**) {
45   test();
46   static_assert(test());
47 
48   return 0;
49 }
50