interface Animal{}

class Dog: Animal{}

class Cat: Animal{}

​

import std.stdio;

void main()

{

    Animal[] x;

    x ~= new Cat();

    x ~= new Dog();

    x ~= new Cat();

    writeln(typeid(x[0]));

    writeln(typeid(cast(Object)x[0]));

    writeln(cast(void*)x[0]);

    writeln(cast(void*)cast(Object)x[0]);

}