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Re: hmadorf on Lisp vs Fortran - declarations

    Date: Tue, 27 Oct 1992 21:50-0000
    From: moon@cambridge.apple.com (David A. Moon)

    > Date: Mon, 26 Oct 1992 16:19:05 -0500
    > To: info-mcl
    > From: hmadorf@eso.org (by way of alms@cambridge.apple.com (Andrew LM Shalit))
    > ;; Conclusion: the declarations do not help in MCL 2.0f

    I think you've been told this a few times before, but since
    it was sent to info-mcl again I'll say it again, since
    someone should.

    Integer declarations don't make any difference in most Common Lisps,
    since integers have unlimited range.  Try a fixnum declaration
    if that's what you mean.  Of course, you can't compute 200
    factorial within the fixnum range, and you couldn't compute
    it in Fortran either, since Fortran integers have about the
    same limited range as Lisp fixnums.  So I don't know
    what you think this part of your benchmark proves; it doesn't
    seem to have much to do with what you're trying to measure.

In black & white, the factorial 200 test spends most of it's time
allocating and processing bignums etc. It really does not test the sort
number crunching suitable for the normal work of "scientists, whose
experience is in numerical computing".

Yet again Lisp has shot itself in the foot. By allowing inexperienced
users the power to compute things that are out of the bounds of
possibility in most languages, Lisp gets bad marks for poor performance.

Many's the time that I have heard that Lisp is inappropriate for almost
anything other than academic exercises because it conses and garbage
collects! Ahhh... just because Lisp allows you to be dirty, does not
mean that you have to be. Many a major Lisp application runs with
negligable consing or GC.

So, to my point, why don't Lisps issue an automatic compiler warning
when declarations are being ignored. 

I rejoice that this time the lecturer asked the experts what was going
on, rather than marching forward blind and damning Lisp with ever step.
Thank you Hans-Martin Adorf.