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From: db@witzend.East.Sun.COM (David Brownell)
Newsgroups: comp.lang.scheme
Subject: Re: XScheme numbers representation?
Summary: UCB mp(3x) is also an option
Message-ID: <2348@east.East.Sun.COM>
Date: 6 Aug 90 23:12:45 GMT
References: <1990Jul23.075719.8352@agate.berkeley.edu>
	<.648809664@dutepp1> <4483@jato.Jpl.Nasa.Gov>
Sender: news@east.East.Sun.COM
Reply-To: db@east.sun.com (David Brownell)
Organization: Sun Microsystems, Billerica MA
Lines: 19

> >The bignumber system as supported by most Scheme implementations (except
> >XScheme) doesn't exist in C.

>   You're absolutely right, bignums are a big deal to implement.  One 
>   approach to cutting short the work would be to lift the bignum code
>   from MIT CScheme and attempt to sew it into XScheme.

Many systems have the mp(3x) library, callable from C, which provides
multiple precision integer math.  The worst problem looks to be that
it's oriented to hex I/O, but I suspect that with sources (it's UCB
code I think) that's probably not painful to fix.

I suspect it'd be less work to use this than to take code out of CScheme,
but who knows.


David Brownell			db@east.sun.com.

"What's the network equivalent of 'the rough section of town'?"