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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
// static constexpr bool empty() noexcept;
#include <cassert>
#include <concepts>
#include <ranges>
#include <utility>
#include "test_macros.h"
struct Empty {};
struct BigType {
char buffer[64] = {10};
};
template <typename T>
constexpr void test_empty(T value) {
using SingleView = std::ranges::single_view<T>;
{
std::same_as<bool> decltype(auto) result = SingleView::empty();
assert(result == false);
static_assert(noexcept(SingleView::empty()));
}
{
SingleView sv{value};
std::same_as<bool> decltype(auto) result = std::ranges::empty(sv);
assert(result == false);
static_assert(noexcept(std::ranges::empty(sv)));
}
{
const SingleView sv{value};
std::same_as<bool> decltype(auto) result = std::ranges::empty(sv);
assert(result == false);
static_assert(noexcept(std::ranges::empty(std::as_const(sv))));
}
}
constexpr bool test() {
test_empty<int>(92);
test_empty<Empty>(Empty{});
test_empty<BigType>(BigType{});
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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