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Re: more on BOGUS-FIXNUMS



> Date: Thu, 21 Jul 88 10:35:52 MDT
> From: sandra <(Sandra J Loosemore)sandra%cdr@edu.utah.cs>
> Subject: Re: more on BOGUS-FIXNUMS

> Actually, I don't think we have to worry particularly about supporting
> micros.  According to Stan, it appears that the Lisp with the smallest
> fixnum range is actually Franz Lisp, which uses a separate spaces
> implementation with fixnums in the range [-1024, 1023].

That is not correct.  Fixnums in Franz are 32 bits, or at least they
are on VAX or 68k.  Look at any Franz manual or write some Franz code
that declares fixnums or uses fixed-type arithmetic if you want to
check this.

The [-1024, 1023] is for *small fixnums*.  They are just like normal
fixnums but preallocated.  The "separate space" notion is sometimes
used to check whether an integer is in the range of preallocated ones,
but Franz in general uses bibop (the high order bits of the address
are an index into a type table).

BTW, as I have mentioned before, Franz and KCL are vary similar in
this respect.

-- Jeff