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(declare (type fixnum ---)) considered etc.
- To: navajo!DCP%QUABBIN.SCRC.Symbolics.COM@navajo.stanford.edu
- Subject: (declare (type fixnum ---)) considered etc.
- From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
- Date: Thu, 24 Jul 86 13:29:12 PDT
- Cc: navajo!common-lisp%SU-AI.ARPA@navajo.stanford.edu
- In-reply-to: David C. Plummer's message of Thu, 24 Jul 86 13:34 EDT
Re: If you really want to go least-common-denominator, you will probably
have to settle for 7 guarenteed bits, or maybe 8 or 9; I can't remember
how big MacLisp fixnums are.
MacLisp's fixnums are 36 bits in width; Interlisp-D's fixnums are 32 bits
wide (they are called FIXP's in Interlisp parlance).
There seems to be some confusion between the type FIXNUM with the (informal)
type "non-consing, small fixnum". Interlisp call's the latter variety
SMALLP's, and on the D machines they are 17 bits wide; MacLisp generally
guarantees non-consing behaviour only for a modest subrange of fixnums, but
the infamous NCOMPLR handles full 36-bit fixnums and generally avoids consing
them by using "strong typing" compiler techniques.
-- JonL --