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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
// UNSUPPORTED: libcpp-has-no-incomplete-ranges
// template<borrowed_range R>
// requires convertible-to-non-slicing<iterator_t<R>, I> &&
// convertible_to<sentinel_t<R>, S>
// constexpr subrange(R&& r, make-unsigned-like-t<iter_difference_t<I>> n)
// requires (K == subrange_kind::sized);
#include <ranges>
#include <cassert>
struct BorrowedRange {
constexpr explicit BorrowedRange(int* b, int* e) : begin_(b), end_(e) { }
constexpr int* begin() const { return begin_; }
constexpr int* end() const { return end_; }
private:
int* begin_;
int* end_;
};
namespace std::ranges {
template <>
inline constexpr bool enable_borrowed_range<::BorrowedRange> = true;
}
constexpr bool test() {
int buff[] = {1, 2, 3, 4, 5, 6, 7, 8};
using Subrange = std::ranges::subrange<int*, int*, std::ranges::subrange_kind::sized>;
// Test with an empty range
{
BorrowedRange range(buff, buff);
Subrange subrange(range, 0);
assert(subrange.size() == 0);
}
// Test with non-empty ranges
{
BorrowedRange range(buff, buff + 1);
Subrange subrange(range, 1);
assert(subrange.size() == 1);
}
{
BorrowedRange range(buff, buff + 2);
Subrange subrange(range, 2);
assert(subrange[0] == 1);
assert(subrange[1] == 2);
assert(subrange.size() == 2);
}
{
BorrowedRange range(buff, buff + 8);
Subrange subrange(range, 8);
assert(subrange[0] == 1);
assert(subrange[1] == 2);
// ...
assert(subrange[7] == 8);
assert(subrange.size() == 8);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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