xref: /llvm-project/libcxx/test/std/ranges/range.factories/range.single.view/ctor.default.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 // single_view() requires default_initializable<T> = default;
12 
13 #include <ranges>
14 #include <cassert>
15 
16 #include "test_macros.h"
17 
18 struct BigType { char buffer[64] = {10}; };
19 
20 template<bool DefaultCtorEnabled>
21 struct IsDefaultConstructible {
22   IsDefaultConstructible() requires DefaultCtorEnabled = default;
23 };
24 
test()25 constexpr bool test() {
26   static_assert( std::default_initializable<std::ranges::single_view<IsDefaultConstructible<true>>>);
27   static_assert(!std::default_initializable<std::ranges::single_view<IsDefaultConstructible<false>>>);
28 
29   {
30     std::ranges::single_view<BigType> sv;
31     assert(sv.data()->buffer[0] == 10);
32     assert(sv.size() == 1);
33   }
34   {
35     const std::ranges::single_view<BigType> sv;
36     assert(sv.data()->buffer[0] == 10);
37     assert(sv.size() == 1);
38   }
39 
40   return true;
41 }
42 
main(int,char **)43 int main(int, char**) {
44   test();
45   static_assert(test());
46 
47   return 0;
48 }
49