Re: Visibility issue

[Daniel <danielnorberto@gmail.com>]

> hierarchy be a child hierarchy of your interface hierarchy. It's undoubtedly 
> possible to design such a system so your implementation hierarchy does not need 
> to be a child hierarchy, but where things are declared and what is visible where 
> would be different.
Thank you for your answer. ¿ Do you know some idea or design pattern to achieve this?
I didn't write it in the example for simplicity, but the user have to set a callback function.
This callback function is triggered in the internal implementation hierarchy packages. Let me show you. the questions are inside comments:

--- API SIDE: -----
package API.Callbacks
   type Handle is tagged private
   type pointer_to_Procedure is access procedure (Self : API.CAllbacks.Handle );
   procedure Set_Callback (Self: in out API_HandleCallBack; cp: CallbackProcedure  );

private   
   type Handle is tagged record
      Hidden : Natural;
   end record;
  procedure Hidden_constructor (S: in out Handle'Class ; Hidden_content :Natural);
---------------
----- IMPLEMENTING SIDE: --------
with API.Callbacks;
package body Internal.TASKS_Callbacks is

task body Caller is

 MyHandle : API.Handle;
 cp: CallbackProcedure := Get_from_pool_of_callbacks;
begin
   --Cannot access to private part for API.Handle from here :(
   -- Just want to set a hidden content from here using Hidden_Constructor and later call:
   cp (MyHandle);
end Caller;