Aubrey Jaffer <xxxxxx@alum.mit.edu> writes:

> We worked through this issue in SRFI-70.  I think SRFI-70's treatment
> is Schemely, compatible with IEEE-754, and doesn't unnecessarily
> constrain implementations:
>
>   The notation 0/0 is used within this report to designate a numerical
>   error-object.  A numerical function may return such an object when
>   no other number (including real infinities) is the correct value.
>   An implementation may report a violation of an implementation
>   restriction in any calculation for which the result would be 0/0.

It's not compatible with IEEE-754 because it doesn't guarantee that
by default operations like (/ 0.0 0.0) produce NaN.

--
   __("<         Marcin Kowalczyk
   \__/       xxxxxx@knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/