Re: Reemergence of predefined equality operator...

[dewar@gnat.com (Robert Dewar)]

Vincent Marciante <marciant_remove@earthlink.net> wrote in message news:<3D488F3D.6186@earthlink.net>...
> If overriding of predefined "=" was disallowed in the 
> future (not practical?) wouldn't that solve the problem 
> well?   Is that really really not practical?

Of course that's not practical. Do you really think vendors
would pay any attention if the Ada design went berserk and
started adding gratuitous non-upward compatible changes?
Remember that it is possible to redefine "=" in Ada 83
as well.

A criterion for Ada 95 was no non-upwards compatible changes (unless a
VERY good argument could be given,
e.g. optional package bodies and the (<>) generic
stuff, where Ada 83 was clearly broken).

That criterion has to be applied even more strongly
for any future revisions to Ada. 

One thing to be careful of is that current proposals for
revisions to Ada are coming mostly from hobbyists and language
designers, not from actual users writing large
application programs. That means one needs to be even more
cautious in countenancing changes.

Actually in practice, I think any new "Ada0X" will be no
more than a list of suggestions for enhancements and new
ideas. I think there will be almost no commercial pressure
to implement such a new standard in some validated form
for the forseeable future (after all, look how long it took
for the C standard to take hold).