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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<class T>
// class empty_view;
#include <ranges>
#include <cassert>
#include "test_macros.h"
template<class T>
constexpr void testType() {
static_assert(std::ranges::range<std::ranges::empty_view<T>>);
static_assert(std::ranges::range<const std::ranges::empty_view<T>>);
static_assert(std::ranges::view<std::ranges::empty_view<T>>);
std::ranges::empty_view<T> empty;
assert(empty.begin() == nullptr);
assert(empty.end() == nullptr);
assert(empty.data() == nullptr);
assert(empty.size() == 0);
assert(empty.empty() == true);
assert(std::ranges::begin(empty) == nullptr);
assert(std::ranges::end(empty) == nullptr);
assert(std::ranges::data(empty) == nullptr);
assert(std::ranges::size(empty) == 0);
assert(std::ranges::empty(empty) == true);
}
struct Empty {};
struct BigType { char buff[8]; };
template<class T>
concept ValidEmptyView = requires { typename std::ranges::empty_view<T>; };
constexpr bool test() {
// Not objects:
static_assert(!ValidEmptyView<int&>);
static_assert(!ValidEmptyView<void>);
testType<int>();
testType<const int>();
testType<int*>();
testType<Empty>();
testType<const Empty>();
testType<BigType>();
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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