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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
// friend constexpr void iter_swap(const iterator& x, const iterator& y);
#include <cassert>
#include <ranges>
#include "../types.h"
using NonSwappableView = BufferView<copying_iterator<int*>>;
static_assert(std::ranges::input_range<NonSwappableView>);
static_assert(!std::indirectly_swappable<std::ranges::iterator_t<NonSwappableView>>);
constexpr bool test() {
int buffer[4][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}, {13, 14, 15, 16}};
{
std::ranges::join_view jv(buffer);
auto iter1 = jv.begin();
auto iter2 = std::next(jv.begin());
assert(buffer[0][0] == 1);
assert(buffer[0][1] == 2);
std::ranges::iter_swap(iter1, iter2);
assert(buffer[0][0] == 2);
assert(buffer[0][1] == 1);
static_assert(noexcept(std::ranges::iter_swap(iter1, iter2)));
}
{
// iter_move calls inner's iter_swap
IterMoveSwapAwareView inners[1] = {buffer[0]};
std::ranges::join_view jv(inners);
auto it1 = jv.begin();
auto it2 = std::ranges::next(it1);
const auto& iter_swap_called_times = jv.base().begin()->iter_swap_called;
assert(iter_swap_called_times == 0);
assert(buffer[0][0] == 2);
assert(buffer[0][1] == 1);
std::ranges::iter_swap(it1, it2);
assert(buffer[0][0] == 1);
assert(buffer[0][1] == 2);
assert(iter_swap_called_times == 1);
}
{
// LWG3517 `join_view::iterator`'s `iter_swap` is underconstrained
// `iter_swap` should not be defined if Inner's iterator does not indirectly_swappable
NonSwappableView inners[2] = {buffer[0], buffer[1]};
std::ranges::join_view jv(inners);
using Iter = std::ranges::iterator_t<decltype(jv)>;
static_assert(!std::indirectly_swappable<Iter>);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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