mark@BUDDY.CSS.GOV (Mark Nelson) (12/07/88)
--Question:
--I am working on a method for inheriting procedures, types and packages
-- from within an Ada prospective. I am developing
-- a full Ada toolkit that will use the previously defined Ada binding to
-- the X Window System. I seem to run into a problem exploiting the idea of
-- nested generics and visibility.
--
-- I am requesting help from other programmers that have used OOD in their
-- design and used inheritance. Can it be done, or is it only a mirage
-- from the Ada world.
--
-- I am trying to make the elemnents of a specific package visible within a
-- package that is nested two levels down.
--
-- Enclosed is an example of what is being attempted. I'm not sure I
-- fully have the concept down so be kind.
------------------
package Xt_Super is
generic
package Super is
type This_Type is (One, Two, Three);
end Super;
end Xt_Super;
------------------
with Xt_Super;
package Xt_Sub_Class is
generic
package Sub_Class is
package Super_Class is new Xt_Super.Super;
use Super_Class;
type This_Rec is
record
First_Element : This_Type;
end record;
end Sub_Class;
end Xt_Sub_Class;
-------------------
--vvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
--and on to the problem
--vvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
with Xt_Sub_Class;
package Xt_My_Class is
generic
package My_Class is
package New_Super_Class is new Xt_Sub_Class.Sub_Class;
use New_Super_Class;
type New_Record is
record
The_Element : This_Type; --PROBLEM, How do I make this visible;
end record;
end My_Class;
end Xt_My_Class;
--I am trying to make pieces visible that should have a way to be done.
--Being pretty sure that this should be able to be done some how, I
--turn to my fellow programmers. I am sure I am missing something? But what?
--
--Please reply directly and I will post solutions to this inheritance
--problem once I figure it all out.
--
--Thanks for the flame mom!
--
--
-- ____ _ ____
-- / / / | / / /
-- /___ /__| / /
-- / / | / /
-- /___/ / | / /____/
--
--Mark A. Nelson |
--Geophysics Division | {ucbvax!ucsd,uunet!seismo}!esosun!mark
--Science Applications Int'l Corp. | esosun!mark@seismo.css.gov
--San Diego, CA |