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Re: reading NaNs

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

Aubrey Jaffer <agj@xxxxxxxxxxxx> 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
   \__/       qrczak@xxxxxxxxxx
    ^^     http://qrnik.knm.org.pl/~qrczak/