2010/9/1 Stephen Bloch <sbl...@adelphi.edu>:
> I've been having an interesting discussion off-list with David Kay, but have
> concluded
> that we need the expertise of somebody more knowledgeable about Scheme/Racket
> and its philosophy.
Apropos philosophy. The rrrs mailing list is available online and
contains various
exchanges on inexact numbers. Here is one from Guy Steele with the
memorable quote:
INEXACT NUMBERS ARE NOT NUMBERS
INEXACT NUMBERS ARE NOT NUMBERS
INEXACT NUMBERS ARE NOT NUMBERS
They do not obey the rules followed by numbers, because they cannot.
Inexact numbers only represent our -approximate- -knowledge- about numbers.
See
http://groups.csail.mit.edu/mac/ftpdir/scheme-mail/HTML/rrrs-1989/msg00178.html
Here and there you'll see ideas that didn't catch on. Some of these
are still available.
The syntax 12## is still legal. It signifies that the last two
digits are unknown.
In Racket it evaluates to 1200.0, though one might argue 1250.0 were a
better idea.
Back then they also discussed other representations of inexact numbers
than floating point.
Were there ever released a Scheme with, say, interval representation?
--
Jens Axel Søgaard
_________________________________________________
For list-related administrative tasks:
http://lists.racket-lang.org/listinfo/users
