67 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// template<class T>12// class empty_view;13 14#include <ranges>15#include <cassert>16 17#include "test_macros.h"18 19template<class T>20constexpr void testType() {21 static_assert(std::ranges::range<std::ranges::empty_view<T>>);22 static_assert(std::ranges::range<const std::ranges::empty_view<T>>);23 static_assert(std::ranges::view<std::ranges::empty_view<T>>);24 25 std::ranges::empty_view<T> empty;26 27 assert(empty.begin() == nullptr);28 assert(empty.end() == nullptr);29 assert(empty.data() == nullptr);30 assert(empty.size() == 0);31 assert(empty.empty() == true);32 33 assert(std::ranges::begin(empty) == nullptr);34 assert(std::ranges::end(empty) == nullptr);35 assert(std::ranges::data(empty) == nullptr);36 assert(std::ranges::size(empty) == 0);37 assert(std::ranges::empty(empty) == true);38}39 40struct Empty {};41struct BigType { char buff[8]; };42 43template<class T>44concept ValidEmptyView = requires { typename std::ranges::empty_view<T>; };45 46constexpr bool test() {47 // Not objects:48 static_assert(!ValidEmptyView<int&>);49 static_assert(!ValidEmptyView<void>);50 51 testType<int>();52 testType<const int>();53 testType<int*>();54 testType<Empty>();55 testType<const Empty>();56 testType<BigType>();57 58 return true;59}60 61int main(int, char**) {62 test();63 static_assert(test());64 65 return 0;66}67