#include <iostream>
 
enum class Some_Enum_Class
{
	A, B, C
};
struct Base {
    void * data;
    Base(){}
    virtual ~Base(){}
    // ...
    virtual bool Read(){std::cout << "hello from base" << std::endl;}
};
template <Some_Enum_Class T>
struct Derived : Base {
    // T-specific interface to deal with Base::data
    bool Read() { std::cout << "hello from Derived" << std::endl; }
};
 
 
int main() {
	Derived <Some_Enum_Class::A> * D = new Derived <Some_Enum_Class::A>;
    Base * B = (Base*) D;
    void* b = (void*) B;
    Base * B2 = (Base*) b;
    B2->Read();
	return 0;
}

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