How to access parent class/object?

["Adrian Hoe" <byhoe@greenlime.com>]

Hi,

I have the following codes (abbreviated):

package A is
   type A_Object is tagged private;
...
end A;

package B is
   type B_Object is new A_Object with private;
...
end B;

package C is
   type C_Object is new B_Object with private;
...
end C;

package D is
   type D_Object is new C_Object with private;
...
end D;

Now, I have the following declaration:

My_D_Object is D.D_Object;

How can I reference the parent objects?

procedure Process_C (C_Obj : access C_Object);
procedure Process_D (D_Obj : access D_Object);

How can I pass C_Object and D_Object into Process_C and Process_D
respectively given only My_D_Object is D.D_Object?

Thanks.
--
Adrian Hoe