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_empty 13 14 #include <type_traits> 15 16 template <class T> 17 void test_is_empty() 18 { 19 static_assert( std::is_empty<T>::value, ""); 20 static_assert( std::is_empty<const T>::value, ""); 21 static_assert( std::is_empty<volatile T>::value, ""); 22 static_assert( std::is_empty<const volatile T>::value, ""); 23 } 24 25 template <class T> 26 void test_is_not_empty() 27 { 28 static_assert(!std::is_empty<T>::value, ""); 29 static_assert(!std::is_empty<const T>::value, ""); 30 static_assert(!std::is_empty<volatile T>::value, ""); 31 static_assert(!std::is_empty<const volatile T>::value, ""); 32 } 33 34 class Empty 35 { 36 }; 37 38 class NotEmpty 39 { 40 virtual ~NotEmpty(); 41 }; 42 43 union Union {}; 44 45 struct bit_zero 46 { 47 int : 0; 48 }; 49 50 int main() 51 { 52 test_is_not_empty<void>(); 53 test_is_not_empty<int&>(); 54 test_is_not_empty<int>(); 55 test_is_not_empty<double>(); 56 test_is_not_empty<int*>(); 57 test_is_not_empty<const int*>(); 58 test_is_not_empty<char[3]>(); 59 test_is_not_empty<char[3]>(); 60 test_is_not_empty<Union>(); 61 test_is_not_empty<NotEmpty>(); 62 63 test_is_empty<Empty>(); 64 test_is_empty<bit_zero>(); 65 } 66
