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 // <functional> 11 12 // make sure that we can hash enumeration values 13 // Not very portable 14 15 #include <__config> 16 17 #if _LIBCPP_STD_VER > 11 18 19 #include <functional> 20 #include <cassert> 21 #include <type_traits> 22 #include <limits> 23 24 enum class Colors { red, orange, yellow, green, blue, indigo, violet }; 25 enum class Cardinals { zero, one, two, three, five=5 }; 26 enum class LongColors : short { red, orange, yellow, green, blue, indigo, violet }; 27 enum class ShortColors : long { red, orange, yellow, green, blue, indigo, violet }; 28 enum class EightBitColors : uint8_t { red, orange, yellow, green, blue, indigo, violet }; 29 30 enum Fruits { apple, pear, grape, mango, cantaloupe }; 31 32 template <class T> 33 void 34 test() 35 { 36 static_assert((std::is_base_of<std::unary_function<T, std::size_t>, 37 std::hash<T> >::value), ""); 38 typedef typename std::underlying_type<T>::type under_type; 39 40 std::hash<T> h1; 41 std::hash<under_type> h2; 42 for (int i = 0; i <= 5; ++i) 43 { 44 T t(static_cast<T> (i)); 45 if (sizeof(T) <= sizeof(std::size_t)) 46 assert(h1(t) == h2(static_cast<under_type>(i))); 47 } 48 } 49 50 int main() 51 { 52 test<Cardinals>(); 53 54 test<Colors>(); 55 test<ShortColors>(); 56 test<LongColors>(); 57 test<EightBitColors>(); 58 59 test<Fruits>(); 60 } 61 #else 62 int main () {} 63 #endif 64
