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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, c++20
// friend constexpr iterator operator-(iterator i, difference_type n);
// friend constexpr difference_type operator-(const iterator& x, const iterator& y);
#include <cassert>
#include <concepts>
#include <cstddef>
#include <ranges>
constexpr bool test() {
// <iterator> - difference_type
{
using Iter = std::ranges::iterator_t<std::ranges::repeat_view<int>>;
std::ranges::repeat_view<int> v(0);
Iter iter = v.begin() + 10;
assert(iter - 5 == v.begin() + 5);
static_assert(std::same_as<decltype(iter - 5), Iter>);
}
// <iterator> - <iterator>
{
// unbound
{
std::ranges::repeat_view<int> v(0);
auto iter1 = v.begin() + 10;
auto iter2 = v.begin() + 5;
assert(iter1 - iter2 == 5);
static_assert(std::same_as<decltype(iter1 - iter2), ptrdiff_t>);
}
// bound && signed bound sentinel
{
std::ranges::repeat_view<int, int> v(0, 20);
auto iter1 = v.begin() + 10;
auto iter2 = v.begin() + 5;
assert(iter1 - iter2 == 5);
static_assert(std::same_as<decltype(iter1 - iter2), int>);
}
// bound && unsigned bound sentinel
{
std::ranges::repeat_view<int, unsigned> v(0, 20);
auto iter1 = v.begin() + 10;
auto iter2 = v.begin() + 5;
assert(iter1 - iter2 == 5);
static_assert(sizeof(decltype(iter1 - iter2)) > sizeof(unsigned));
}
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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