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-exception
6//
7//===----------------------------------------------------------------------===//
8
9// type_traits
10
11// is_reference
12
13#include <type_traits>
14#include <cstddef> // for std::nullptr_t
15#include "test_macros.h"
16
17template <class T>
18void test_is_reference()
19{
20 static_assert( std::is_reference<T>::value, "");
21 static_assert( std::is_reference<const T>::value, "");
22 static_assert( std::is_reference<volatile T>::value, "");
23 static_assert( std::is_reference<const volatile T>::value, "");
24#if TEST_STD_VER > 14
25 static_assert( std::is_reference_v<T>, "");
26 static_assert( std::is_reference_v<const T>, "");
27 static_assert( std::is_reference_v<volatile T>, "");
28 static_assert( std::is_reference_v<const volatile T>, "");
29#endif
30}
31
32template <class T>
33void test_is_not_reference()
34{
35 static_assert(!std::is_reference<T>::value, "");
36 static_assert(!std::is_reference<const T>::value, "");
37 static_assert(!std::is_reference<volatile T>::value, "");
38 static_assert(!std::is_reference<const volatile T>::value, "");
39#if TEST_STD_VER > 14
40 static_assert(!std::is_reference_v<T>, "");
41 static_assert(!std::is_reference_v<const T>, "");
42 static_assert(!std::is_reference_v<volatile T>, "");
43 static_assert(!std::is_reference_v<const volatile T>, "");
44#endif
45}
46
47class incomplete_type;
48
49class Empty
50{
51};
52
53class NotEmpty
54{
55 virtual ~NotEmpty();
56};
57
58union Union {};
59
60struct bit_zero
61{
62 int : 0;
63};
64
65class Abstract
66{
67 virtual ~Abstract() = 0;
68};
69
70enum Enum {zero, one};
71
72typedef void (*FunctionPtr)();
73
74
75int main(int, char**)
76{
77 test_is_reference<int&>();
78 test_is_reference<int&&>();
79 test_is_not_reference<std::nullptr_t>();
80 test_is_not_reference<void>();
81 test_is_not_reference<int>();
82 test_is_not_reference<double>();
83 test_is_not_reference<char[3]>();
84 test_is_not_reference<char[]>();
85 test_is_not_reference<void *>();
86 test_is_not_reference<FunctionPtr>();
87 test_is_not_reference<Union>();
88 test_is_not_reference<incomplete_type>();
89 test_is_not_reference<Empty>();
90 test_is_not_reference<bit_zero>();
91 test_is_not_reference<int*>();
92 test_is_not_reference<const int*>();
93 test_is_not_reference<Enum>();
94 test_is_not_reference<NotEmpty>();
95 test_is_not_reference<Abstract>();
96 test_is_not_reference<int(int)>();
97 test_is_not_reference<int Empty::*>();
98 test_is_not_reference<void (Empty::*)(int)>();
99
100
101 return 0;
102}
103

source code of libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.pass.cpp