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*To*: Aubrey Jaffer <agj@xxxxxxxxxxxx>*Subject*: Re: Wrapping up SRFI-70*From*: Per Bothner <per@xxxxxxxxxxx>*Date*: Mon, 15 Aug 2005 09:38:34 -0700*Cc*: srfi-70@xxxxxxxxxxxxxxxxx*Delivered-to*: srfi-70@xxxxxxxxxxxxxxxxx*In-reply-to*: <20050815021823.42DF31B77B4@xxxxxxxxxxxxxxxx>*References*: <20050810030837.1C5711B77B4@xxxxxxxxxxxxxxxx> <524C370E-9E6F-48A4-ABC8-0E2C8AFEB678@xxxxxxxxxxxxxxx> <42F98CF3.8040805@xxxxxxxxxxx> <20050815021823.42DF31B77B4@xxxxxxxxxxxxxxxx>*User-agent*: Mozilla Thunderbird 1.0.6-1.1.fc4 (X11/20050720)

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 #i-1/0 #|kawa:23|# (log neg-inf) #i1/0+3.141592653589793i #|kawa:26|# (sqrt neg-inf) #i+1/0i Kawa allows complex numbers with infinite components. Whether this is "correct" or accidental I don't know. Also I got: #|kawa:29|# (angle inf) 0 #|kawa:30|# (angle neg-inf) 0 -- --Per Bothner per@xxxxxxxxxxx http://per.bothner.com/

**Follow-Ups**:**Re: Wrapping up SRFI-70***From:*Aubrey Jaffer

**References**:**Wrapping up SRFI-70***From:*Aubrey Jaffer

**Re: Wrapping up SRFI-70***From:*Bradley Lucier

**Re: Wrapping up SRFI-70***From:*Per Bothner

**Re: Wrapping up SRFI-70***From:*Aubrey Jaffer

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