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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// reverse_view() requires default_initializable<V> = default;
#include <ranges>
#include <cassert>
#include "types.h"
enum CtorKind { DefaultCtor, PtrCtor };
template<CtorKind CK>
struct BidirRangeWith : std::ranges::view_base {
int *ptr_ = nullptr;
constexpr BidirRangeWith() requires (CK == DefaultCtor) = default;
constexpr BidirRangeWith(int *ptr);
constexpr bidirectional_iterator<int*> begin() { return bidirectional_iterator<int*>{ptr_}; }
constexpr bidirectional_iterator<const int*> begin() const { return bidirectional_iterator<const int*>{ptr_}; }
constexpr bidirectional_iterator<int*> end() { return bidirectional_iterator<int*>{ptr_ + 8}; }
constexpr bidirectional_iterator<const int*> end() const { return bidirectional_iterator<const int*>{ptr_ + 8}; }
};
constexpr bool test() {
{
static_assert( std::default_initializable<std::ranges::reverse_view<BidirRangeWith<DefaultCtor>>>);
static_assert(!std::default_initializable<std::ranges::reverse_view<BidirRangeWith<PtrCtor>>>);
}
{
std::ranges::reverse_view<BidirRangeWith<DefaultCtor>> rev;
assert(rev.base().ptr_ == nullptr);
}
{
const std::ranges::reverse_view<BidirRangeWith<DefaultCtor>> rev;
assert(rev.base().ptr_ == nullptr);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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