Re: Type extension with GNAT

[usagi@cix.compulink.co.uk ("Jim Wall")]

Erm,

I get the feeling that you've tried something like:

type One is tagged record
   A : ?
   B : ?
end record;

procedure A ( a : ?;
              b : ? );
              <new package>

type Two is new One with
   C : ?
end record

procedure A ( a : ?;
              b : ?;
              c : ? );
              ????

assuming this (and forgive the pseudo-code) then, then what you're after 
is simply

procedure A ( AA : One );
 
and

procedure B ( BB : Two );



Here B 

If this is so, I suggest that if your original 'point' procedure were to 
accept the actual type Two_D_Point and the version for Three_D_Point 
(being the extended Two_D_Point) then the problem wouldn't arise.