Re: Ada Language Revision Cycle

[billwolf%hazel.cs.clemson.edu@hubcap.clemson.edu (William Thomas Wolfe, 2847 )]

From eachus@aries.mitre.org (Robert I. Eachus):
>      My current guess (not my preferences, just a guess as to what
> will happen) is that the first revision will be a very minor one, with
> the largest changes being things like replacing ASCII with Latin-1,
> allowing literals from other character sets, unsigned types (but not
> as predefined integer types), dynamic prioities, and better support
> for entry families.  The following revison can deal with evolution.

   What would be the rationale for deferring evolution another 5 years?

   It seems to me that it is at least as important to modernize software
   technology as it is to modernize hardware technology (e.g., aircraft)!

   The area in which object-orientation will provide the maximum payoff,
   that of management information systems, is of particular importance
   to the DoD right now -- witness the spare parts scandals!  Therefore I
   consider it especially important that object-orientation be addressed.
  
>      There may be some extensions to make OOP easier, but don't expect
> much in the way of changes.  Just the ability to do what you can do
> already in a much more elegant way.  (Which is a lot.  The only major
> feature not directly supported in Ada is multiple inheritance, and
> overload resolution makes that a big can of worms.)

   As I mentioned in an earlier article, there is recent work in the
   area of combining types, inheritance, and prototyping (one reference
   being "Object Specialization", ACM Transactions on Information Systems,
   April 1989; I am in the process of investigating others) which basically
   eliminates both the need and the desire for multiple inheritance.  Though
   this particular paper isn't easy reading (it helps a LOT to translate the
   Smalltalk notation into a more Ada-like notation), the ideas in it seem
   to be both analytically and intuitively quite strongly appealing.  With
   minor adjustments, these mechanisms could fit right into Ada very nicely!!

   Five years from now is plenty of time to get an extremely strong proposal
   together.  If Ada *will* be open to such a change in five years, then it
   will find itself very well-positioned to enter the next century.  But what
   about the five years between now and then?


   Bill Wolfe, wtwolfe@hubcap.clemson.edu