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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
// <ranges>
// constexpr Pred const& pred() const;
#include <ranges>
#include <cassert>
#include <concepts>
struct Range : std::ranges::view_base {
int* begin() const;
int* end() const;
};
struct Pred {
bool operator()(int, int) const;
int value;
};
constexpr bool test() {
{
Pred pred{42};
std::ranges::chunk_by_view<Range, Pred> const view(Range{}, pred);
std::same_as<Pred const&> decltype(auto) result = view.pred();
assert(result.value == 42);
// Make sure we're really holding a reference to something inside the view
assert(&result == &view.pred());
}
// Same, but calling on a non-const view
{
Pred pred{42};
std::ranges::chunk_by_view<Range, Pred> view(Range{}, pred);
std::same_as<Pred const&> decltype(auto) result = view.pred();
assert(result.value == 42);
// Make sure we're really holding a reference to something inside the view
assert(&result == &view.pred());
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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