Re: [Chicken-users] Different factorial results

[Peter Bex]

On Fri, Jun 03, 2011 at 12:49:26PM -0400, John Cowan wrote:
> Steve Graham scripsit:
> 
> > Thanks, Mario.  Worked like a charm.  Why is that not part of the base
> > package?
> 
> Licensing.  The numbers egg has to be GPL, because it depends on the GMP
> (GNU Multi-precision Library) which is GPL.

This is no longer true and hasn't been for over a year now.
The current "numbers" code is a heavily modified version of Scheme48's
code, which is itself based on the MIT Scheme code which was BSD-licensed
at some point in time.

> The overall license for Chicken, however, is BSD.
> There are alternatives to the GMP, but it is
> the gold standard: fast, accurate, space-conserving.

The GMP-based numbers egg was actually very slow because it made heavy
use of finalizers and malloc()ed memory.  The new code is a bit faster.
Probably a GMP-based numbers egg which uses Chicken-managed memory would
be faster still, but the license annoys me and I still have hopes to get
bignums in Chicken core someday :)

It's not in core mostly because it would make things slower (though I'm
not 100% convinced of that; there's type dispatching for fixnums/flonums
already anyway) and because it is an extra-large additional pile of code.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
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