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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
// iterator() requires default_initializable<iterator_t<Base>> = default;
#include <ranges>
#include <tuple>
#include "../types.h"
struct PODIter : IterBase<PODIter> {
int i; // deliberately uninitialised
};
struct IterDefaultCtrView : std::ranges::view_base {
PODIter begin() const;
PODIter end() const;
};
struct IterNoDefaultCtrView : std::ranges::view_base {
cpp20_input_iterator<std::tuple<int>*> begin() const;
sentinel_wrapper<cpp20_input_iterator<std::tuple<int>*>> end() const;
};
template <class View, std::size_t N>
using ElementsIter = std::ranges::iterator_t<std::ranges::elements_view<View, N>>;
static_assert(!std::default_initializable<ElementsIter<IterNoDefaultCtrView, 0>>);
static_assert(std::default_initializable<ElementsIter<IterDefaultCtrView, 0>>);
constexpr bool test() {
using Iter = ElementsIter<IterDefaultCtrView, 0>;
{
Iter iter;
assert(iter.base().i == 0); // PODIter has to be initialised to have value 0
}
{
Iter iter = {};
assert(iter.base().i == 0); // PODIter has to be initialised to have value 0
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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