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bignums are bogus
- To: navajo!DLA%DIAMOND.S4CC.Symbolics.COM@navajo.stanford.edu
- Subject: bignums are bogus
- From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
- Date: Thu, 16 Apr 87 14:00:34 PDT
- Cc: navajo!sandra%orion%cs.utah.edu@navajo.stanford.edu, navajo!common-lisp%sail@navajo.stanford.edu
- In-reply-to: David L. Andre's message of Thu, 16 Apr 87 12:29 EDT
re: I always favored a pair of variables MOST-POSITIVE-BIGNUM and
MOST-NEGATIVE-BIGNUM. :-)
As silly as this may sound, I actually ran up against this. Really!
It turns out that most implementations have the bignum's length stored
in some field of fixed size (say, n bits). I accidentally computed up
such an item on a 3600 about a year or so ago (while writing the
"bignum" paper for the 1986 Lisp conference). It seemed as though
the computation was taking far too long. Ultimately, I tracked it down
to the fact that the ephemeral GC couldn't find enough space to copy
the fool thing (even though it had been created), so it fell into the
debugger, and was trying to print out this loser for me. In base 10!
-- JonL --
P.S. It never finised the base-10-conversion process.