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_default_constructible 13 14 #include <type_traits> 15 16 template <class T> 17 void test_is_default_constructible() 18 { 19 static_assert( std::is_default_constructible<T>::value, ""); 20 static_assert( std::is_default_constructible<const T>::value, ""); 21 static_assert( std::is_default_constructible<volatile T>::value, ""); 22 static_assert( std::is_default_constructible<const volatile T>::value, ""); 23 } 24 25 template <class T> 26 void test_is_not_default_constructible() 27 { 28 static_assert(!std::is_default_constructible<T>::value, ""); 29 static_assert(!std::is_default_constructible<const T>::value, ""); 30 static_assert(!std::is_default_constructible<volatile T>::value, ""); 31 static_assert(!std::is_default_constructible<const volatile T>::value, ""); 32 } 33 34 class Empty 35 { 36 }; 37 38 class NotEmpty 39 { 40 public: 41 virtual ~NotEmpty(); 42 }; 43 44 union Union {}; 45 46 struct bit_zero 47 { 48 int : 0; 49 }; 50 51 class Abstract 52 { 53 public: 54 virtual ~Abstract() = 0; 55 }; 56 57 struct A 58 { 59 A(); 60 }; 61 62 class B 63 { 64 B(); 65 }; 66 67 int main() 68 { 69 test_is_default_constructible<A>(); 70 test_is_default_constructible<Union>(); 71 test_is_default_constructible<Empty>(); 72 test_is_default_constructible<int>(); 73 test_is_default_constructible<double>(); 74 test_is_default_constructible<int*>(); 75 test_is_default_constructible<const int*>(); 76 test_is_default_constructible<char[3]>(); 77 test_is_default_constructible<NotEmpty>(); 78 test_is_default_constructible<bit_zero>(); 79 80 test_is_not_default_constructible<void>(); 81 test_is_not_default_constructible<int&>(); 82 test_is_not_default_constructible<char[]>(); 83 test_is_not_default_constructible<Abstract>(); 84 #if __has_feature(cxx_access_control_sfinae) 85 test_is_not_default_constructible<B>(); 86 #endif 87 } 88