あるいは型情報を外に出すとか
typedef int My_Type;
struct base {
base() {}
virtual ~base() {}
};
template <typename T> struct derived : public base {
typedef T member_type;
T value;
derived(T value) : value(value) {}
};
template <typename T> base* derived_generator(T value) {
return new derived<T>(value);
}
typedef derived <My_Type> My_Derived;
int main ()
{
base* tmp = derived_generator(1);
My_Type value = static_cast<My_Derived*>(tmp)->value;
return 0;
}
爺さんこんなのはどうだい？