//===----------------------------------------------------------------------===//
//
// 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 iter_difference_t<W> operator-(const iterator& x, const sentinel& y)
// requires sized_sentinel_for<Bound, W>;
// friend constexpr iter_difference_t<W> operator-(const sentinel& x, const iterator& y)
// requires sized_sentinel_for<Bound, W>;
#include <ranges>
#include <cassert>
#include "test_macros.h"
#include "test_iterators.h"
#include "../types.h"
template<class T>
concept MinusInvocable = requires(std::ranges::iota_view<T, IntSentinelWith<T>> io) {
io.end() - io.begin();
};
constexpr bool test() {
int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
{
auto outIter = random_access_iterator<int*>(buffer);
std::ranges::iota_view<random_access_iterator<int*>, IntSentinelWith<random_access_iterator<int*>>> io(
outIter, IntSentinelWith<random_access_iterator<int*>>(std::ranges::next(outIter, 8)));
auto iter = io.begin();
auto sent = io.end();
assert(iter - sent == -8);
assert(sent - iter == 8);
}
{
auto outIter = random_access_iterator<int*>(buffer);
const std::ranges::iota_view<random_access_iterator<int*>, IntSentinelWith<random_access_iterator<int*>>> io(
outIter, IntSentinelWith<random_access_iterator<int*>>(std::ranges::next(outIter, 8)));
const auto iter = io.begin();
const auto sent = io.end();
assert(iter - sent == -8);
assert(sent - iter == 8);
}
{
// The minus operator requires that "W" is an input_or_output_iterator.
static_assert(!MinusInvocable<int>);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}