[R6RS] division by exact zero (again, sorry)

William D Clinger will at ccs.neu.edu
Tue Mar 6 07:24:50 EST 2007

Kent wrote:
> The current draft contains the example:
>   (/ 0 0) => &assertion exception or +nan.0
> At what point did we decide that this could produce +nan.0?

I made the change in revision 806, 30 August 2006.
The log message was:

    Corrected examples for / in document/base.tex.

Examination of the editors' correspondence on that
date shows that Mike and I wanted to correct the
examples in a certain way, but that Kent objected,
advocating semantics that seemed plainly wrong to
me.  Eventually Kent relented in part, and I said
I would make the changes to which I thought Kent
had agreed.  I must have misinterpreted Kent's
position on (/ 0 0).

I would prefer (/ 0 0) be forbidden to evaluate
to any number at all.


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