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From: Jon S Anthony <jsa@synquiry.com>
Subject: Re: Ada OO Mechanism
Date: 1999/05/27
Message-ID: <374DCDED.127A@synquiry.com>#1/1
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NNTP-Posting-Date: Thu, 27 May 1999 19:00:09 EDT
Newsgroups: comp.lang.ada
Date: 1999-05-27T00:00:00+00:00
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> 
> Hyman Rosen <hymie@prolifics.com> wrote:
> >... object-oriented techniques
...
> Again, there are some AI-type object-oriented systems that generate
> new subclasses on the fly, altering their fields and giving them new
> methods.

Right.  This sort of thing is easy in CLOS.  What's more, if you use
the MOP you can even change how dispatching behaves, etc.  Of course,
you also have true multiple dispatch as well.


> These are generally written in Lisp, where one can execute
> data.  To do this in either C++ or Ada, one would have to write
> roughly the equivalent of a Lisp interpreter in the base language,
> and then really write most of the program in that new language.

Right.  Which is why we switched to Lisp (after trying both Ada and
C++ <with Ada by far the better of those two>).  What's more, since
moder CommonLisp implementations come with optimizing _compilers_
built in and dynamically accessible, you'd have to write (or hook to)
optimizing code generators as well.  Otherwise, you'd be sucking wind
in performance.  You'd also have to write/aquire a GC and optimize it.
Of course, if you go to this effort, you may as well bag the original
application and become a Lisp vendor.


> Sam Mize

/Jon

-- 
Jon Anthony
Synquiry Technologies, Ltd. Belmont, MA 02478, 617.484.3383
"Nightmares - Ha!  The way my life's been going lately,
 Who'd notice?"  -- Londo Mollari