1 #include <type_traits> 2 3 class A 4 { 5 public: 6 template<typename X> f1(X x)7 typename std::enable_if<2 << 3,int>::type f1(X x) 8 { 9 return (int)x; 10 }; 11 12 template<typename X> f2(X x)13 typename std::enable_if<!false,int>::type f2(X x) 14 { 15 return (int)x; 16 }; 17 }; 18 19 class B 20 { 21 };