Re: Thus spake the DoD...

[djsalomon@watdaisy.UUCP (Daniel J. Salomon)]

> There is an escape clause in the Ada promulgation.  That allows other
> languages to be used for special applications where there is good reason to
> do so.  At the Common Lisp conference it was said that the ARPA Strategic
> Computing project would have Common Lisp as a major language.  I think there
> is going to be a de facto standard exception for AI programs that let them
> be done in Lisp.

I think that far too much emphasis has been placed on the need for LISP
in AI work.  The things that were novel when LISP was introduced are
not so rare anymore.  Most AI programs written in LISP could be written
equally well or better in other languages.

The real problem is that there is a large body of AI software written
in LISP that will not be easily converted to or rewritten in Ada.  The
effort would be just too massive.  To justify such an endeavor, the
benefits of converting them to Ada would have to be enormous.
Similarly there is a large group of AI programmers who are experts in
LISP who would have to spend (or waste) a great deal of time becoming
equally proficient in Ada and building up the same tools and techniques.

However similar problems exist in other disciplines.  Numerical analysis has
traditionally been done in Fortran, and Fortran is considerably more
similar to Ada than is LISP.  But it will still take a massive amount
of effort to convert all the tried and trusted FORTRAN numerical-
analysis subroutines into Ada.  Any DOD directive requiring the use of
Ada will have to have loopholes because instant conversion is
impossible and foolish.