Göran Weinholt <[email protected]> writes:
> the flmax and flmin procedures from (rnrs) do not handle +nan.0
> correctly:
>
> scheme@(guile-user)> (import (rnrs))
> scheme@(guile-user)> (flmax +inf.0 +nan.0)
> $1 = +inf.0
> scheme@(guile-user)> (flmin -inf.0 +nan.0)
> $2 = -inf.0
>
> The result should be +nan.0. From r6rs-lib: "They always return a NaN
> when one or more of the arguments is a NaN."
Indeed. I had actually carefully implemented 'min' and 'max' according
to R6RS section 11.7.4 (Numerical operations), which states:
For any real number object x:
(max +inf.0 x) => +inf.0
(min -inf.0 x) => -inf.0
and section 3.5 states that NaNs are real number objects.
At first I was baffled by the inconsistency between min/max and
flmin/flmax, but now I see that the R6RS errata corrected this:
The examples for min and max involving infinities should be prefixed by:
"For any real number object x /that is not a NaN/:"
Fixed in b4c55c9ccedd47c16007b590f064ef3bd67565aa.
Thanks!
Mark
