Ada, Eiffel, & language evolution

[wtwolfe@hubcap.clemson.edu (Bill Wolfe)]

From recent e-mail (an Eiffel user): 
> Ada is some sort of dead end. It has nice
> abilities for data abstraction and is certainly a lot better than
> much else. But it hasn't dynamic binding and inheritance, and I
> fear for the result if you throw that in afterwards. Then you
> will end with old features that are just obsolete.

   There is a great need for a single production programming language 
   which supports good software and code engineering practices.  Ada's
   designers were the first to do something serious about it.  There is
   also the need to ensure that this language is modernized so that it
   does not become obsolescent, and Ada should do this as part of its
   controlled revision process.  If the language can revise itself often
   enough to incorporate new developments, yet be stable enough to keep
   up the incentive to make an investment in the current version, then
   it will have done everything that can reasonably be asked of it.

   It seems a little unfair to criticize Ada before its first opportunity
   to demonstrate its ability to incorporate new ideas (Ada 9X).  I know 
   that Eiffel and C++ are very much on the minds of the people who are
   part of the 9X revision team, and I think they should be given a fair
   chance before we decide that Ada is some sort of dead end.  It may in
   fact be the way to reach the kind of standardized, controlled evolution
   we need.  If Ada can't meet the need, and the rationale doesn't hold up,
   then OK, maybe we need to seek another solution and maybe Eiffel will be
   the answer.  But I have confidence that the Ada 9X designers will do a
   good job, and I know of no reason to assume otherwise.  In the meantime,
   both Ada and Eiffel can profit from each other's experiences.  


   Bill Wolfe, wtwolfe@hubcap.clemson.edu