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Re: Wrapping up SRFI-70

This page is part of the web mail archives of SRFI 70 from before July 7th, 2015. The new archives for SRFI 70 contain all messages, not just those from before July 7th, 2015.

Aubrey Jaffer wrote:
I believe that the junking of 0/0 makes SRFI-70 compatible with
IEEE-754.  Do you agree?

It's a bit awkward.  The syntax 0/0 suggests 0/0 is exact.
The 0/0 syntax is extra awkward for an implementation that
defines 1/0 and -1/0 as exact infinities, as Kawa does.

(Exact infinites are an experimental addition in Kawa  I won't claim
they're terribly well-specified or justified.  I think they can be
useful in some situation, such as sentinel values.)

I did find some discrepencies between your specification and Kawa:

#|kawa:21|# (define neg-inf (/ -1.0 0.0))
#|kawa:22|# neg-inf
#|kawa:23|# (log neg-inf)
#|kawa:26|# (sqrt neg-inf)

Kawa allows complex numbers with infinite components.
Whether this is "correct" or accidental I don't know.

Also I got:

#|kawa:29|# (angle inf)
#|kawa:30|# (angle neg-inf)
	--Per Bothner
per@xxxxxxxxxxx   http://per.bothner.com/