Re: Dynamic dispatch and calling parent

[Martin Lorentzon <emwson@emw.ericsson.se>]

>>>>> "Corey" == Corey Minyard <minyard@metronet.com> writes:

    Corey> I am trying to create a dynamically dispached function.  I
    Corey> want the function for the child type to be able to call the
    Corey> parent's function much like you can in Java, Oberon-2, C++,
    Corey> etc.

package root is

   type parent is tagged private;

   procedure foo(this : in parent);

private

   type parent is tagged null record;

end root;
------------------------------------------------------------
package root.child is

   type derived is new parent with private;

   procedure foo(this : in derived);

private

  type derived is new parent with null record;

end root.child;
------------------------------------------------------------
package body root.child is

  procedure foo(this : in derived)
  is
  begin

    -- Call the parent's operation by casting the type
    foo(root.parent(this));

    -- Do some operations on your own
    null;
  end foo;

end root.child;