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Re: small integers

On Sat, 10 Oct 1992, Robert A. Cassels <cassels@cambridge.apple.com>
>>whether the compiler is smart enough to figure this out as well.  In
>>practice, people just say "fixnum" and then complain about how slow
>>arithmetic is in Lisp.  It's infinitely easier just to say, one way or
>>another, that you don't believe overflows will occur in a certain part
>>the program, and that you want to get an error signal if you're wrong.
>This part succinctly captures the dilemma as I see it.  We all agree
>we want fast, efficient, robust code.  And we want it to be easy for the
>programmer to write such code.  Ideally we'd like the compiler and
>to be simple and easy to implement.  A machine that implements integer
>arithmetic "in the instruction set" (c.f. Lisp machines) satisfies the
>constraints nicely.  For most special-purpose C/Fortran machines, the
>of constraints can't be satisfied, and something has to give.

I see the dillema slightly differently. I'd love to write mathematical
using "correct" arithmetic. Unfortunately, its impossible, since any" real"
program that I write runs much too slowly in lisp. For all of its faults,
FORTRAN is still 
extremely efficient for writing number crunching code that marches over
large arrays.

Until a Dylan or Lisp implementation can DEMONSTRATE equivalent efficiency,
I don't
believe it will be taken seriously by your target audience.