1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 // type_traits
11
12 // is_union
13
14 #include <type_traits>
15 #include <cstddef> // for std::nullptr_t
16 #include "test_macros.h"
17
18 template <class T>
test_is_union()19 void test_is_union()
20 {
21 static_assert( std::is_union<T>::value, "");
22 static_assert( std::is_union<const T>::value, "");
23 static_assert( std::is_union<volatile T>::value, "");
24 static_assert( std::is_union<const volatile T>::value, "");
25 #if TEST_STD_VER > 14
26 static_assert( std::is_union_v<T>, "");
27 static_assert( std::is_union_v<const T>, "");
28 static_assert( std::is_union_v<volatile T>, "");
29 static_assert( std::is_union_v<const volatile T>, "");
30 #endif
31 }
32
33 template <class T>
test_is_not_union()34 void test_is_not_union()
35 {
36 static_assert(!std::is_union<T>::value, "");
37 static_assert(!std::is_union<const T>::value, "");
38 static_assert(!std::is_union<volatile T>::value, "");
39 static_assert(!std::is_union<const volatile T>::value, "");
40 #if TEST_STD_VER > 14
41 static_assert(!std::is_union_v<T>, "");
42 static_assert(!std::is_union_v<const T>, "");
43 static_assert(!std::is_union_v<volatile T>, "");
44 static_assert(!std::is_union_v<const volatile T>, "");
45 #endif
46 }
47
48 class Empty
49 {
50 };
51
52 class NotEmpty
53 {
54 virtual ~NotEmpty();
55 };
56
57 union Union {};
58
59 struct bit_zero
60 {
61 int : 0;
62 };
63
64 class Abstract
65 {
66 virtual ~Abstract() = 0;
67 };
68
69 enum Enum {zero, one};
70 struct incomplete_type;
71
72 typedef void (*FunctionPtr)();
73
main()74 int main()
75 {
76 test_is_union<Union>();
77
78 test_is_not_union<std::nullptr_t>();
79 test_is_not_union<void>();
80 test_is_not_union<int>();
81 test_is_not_union<int&>();
82 test_is_not_union<int&&>();
83 test_is_not_union<int*>();
84 test_is_not_union<double>();
85 test_is_not_union<const int*>();
86 test_is_not_union<char[3]>();
87 test_is_not_union<char[]>();
88 test_is_not_union<Enum>();
89 test_is_not_union<FunctionPtr>();
90 test_is_not_union<Empty>();
91 test_is_not_union<bit_zero>();
92 test_is_not_union<NotEmpty>();
93 test_is_not_union<Abstract>();
94 test_is_not_union<incomplete_type>();
95 }
96