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// join_view() requires default_initializable<V> = default;
12
13#include <cassert>
14#include <ranges>
15
16#include "types.h"
17
18struct DefaultView : std::ranges::view_base {
19 int i; // deliberately uninitialised
20
21 ChildView* begin() const;
22 ChildView* end() const;
23};
24
25constexpr bool test() {
26 {
27 std::ranges::join_view<ParentView<ChildView>> jv;
28 assert(std::move(jv).base().ptr_ == globalChildren);
29 }
30
31 // Default constructor should value initialise underlying view
32 {
33 std::ranges::join_view<DefaultView> jv;
34 assert(jv.base().i == 0);
35 }
36
37 static_assert( std::default_initializable<std::ranges::join_view<ParentView<ChildView>>>);
38 static_assert(!std::default_initializable<std::ranges::join_view<CopyableParent>>);
39
40 return true;
41}
42
43int main(int, char**) {
44 test();
45 static_assert(test());
46
47 return 0;
48}
49

source code of libcxx/test/std/ranges/range.adaptors/range.join/ctor.default.pass.cpp