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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
// constexpr iterator(iterator<!Const> i)
// requires Const &&
// convertible_to<iterator_t<V>, OuterIter> &&
// convertible_to<iterator_t<InnerRng>, InnerIter>;
#include <cassert>
#include <ranges>
#include "test_macros.h"
#include "../types.h"
using ConstCompatibleInner = BufferView<int*>;
using ConstIncompatibleInner = BufferView<forward_iterator<const int*>, forward_iterator<const int*>,
bidirectional_iterator<int*>, bidirectional_iterator<int*>>;
template <class Inner>
using ConstCompatibleOuter = BufferView<const Inner*, const Inner*, Inner*, Inner*>;
template <class Inner>
using ConstIncompatibleOuter = BufferView<forward_iterator<const Inner*>, forward_iterator<const Inner*>,
bidirectional_iterator<Inner*>, bidirectional_iterator<Inner*>>;
constexpr bool test() {
int buffer[4][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}, {13, 14, 15, 16}};
{
CopyableChild children[4] = {CopyableChild(buffer[0]), CopyableChild(buffer[1]), CopyableChild(buffer[2]),
CopyableChild(buffer[3])};
std::ranges::join_view jv(ForwardCopyableParent{children});
auto iter1 = jv.begin();
using iterator = decltype(iter1);
using const_iterator = decltype(std::as_const(jv).begin());
static_assert(!std::is_same_v<iterator, const_iterator>);
const_iterator iter2 = iter1;
assert(iter1 == iter2);
// We cannot create a non-const iterator from a const iterator.
static_assert(!std::constructible_from<iterator, const_iterator>);
}
// !convertible_to<inner_iterator, inner_const_iterator>>;
{
ConstIncompatibleInner inners[2] = {buffer[0], buffer[1]};
ConstCompatibleOuter<ConstIncompatibleInner> outer{inners};
std::ranges::join_view jv(outer);
using iterator = decltype(jv.begin());
using const_iterator = decltype(std::as_const(jv).begin());
static_assert(!std::is_same_v<iterator, const_iterator>);
static_assert(!std::constructible_from<const_iterator, iterator>);
static_assert(!std::constructible_from<iterator, const_iterator>);
}
// !convertible_to<outer_iterator, outer_const_iterator>>;
{
ConstCompatibleInner inners[2] = {buffer[0], buffer[1]};
ConstIncompatibleOuter<ConstCompatibleInner> outer{inners};
std::ranges::join_view jv(outer);
using iterator = decltype(jv.begin());
using const_iterator = decltype(std::as_const(jv).begin());
static_assert(!std::is_same_v<iterator, const_iterator>);
static_assert(!std::constructible_from<const_iterator, iterator>);
static_assert(!std::constructible_from<iterator, const_iterator>);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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