Re: gawk infinity issues

[Andrew J. Schorr]

On Fri, Jan 06, 2006 at 09:20:41PM -0500, John Cowan wrote:
> In that case, a --traditional switch or TRADITIONAL environment variable
> could be used to preserve the old behavior.  In 1979, inf and nan were
> not part of the floating-point landscape.

Agreed.  I'm starting to think that this should be controllable by
the user.  For our site, understanding NaN and Inf as numeric values clearly
makes sense.  But others seem to prefer the old traditional behavior.

FYI, "make check" passes all tests with the patch I sent previously.

At the end of the day, the question is what do you want the output
of this command to be:

   Unpatched gawk 3.1.5 on linux:
      $./gawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      0 0 0 0

   And with my patch on linux:
      $ ./gawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      nan nan inf -inf

   Unpatched gawk 3.1.5 on solaris 8/sparc:
      $ ./gawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      0 -NaN 0 -Inf

   Patched gawk on solaris 8:
      $ ./gawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      NaN -NaN Inf -Inf

Other versions of awk:

   Mawk 1.3.3 on linux:
      $ ./mawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      nan nan inf -inf

   Pawk-20030606 on linux:
      $ ./pawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      nan nan inf -inf

   Nawk on Solaris 8/sparc:
      $ nawk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}'
      NaN -NaN Inf -Inf

   Old awk on solaris 8/sparc:
      $ awk 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0; exit}'
      0 0 0 0

   Awka 0.7.5 on linux:
      $ ./awka 'BEGIN {print "nan"+0,"-nan"+0,"inf"+0,"-inf"+0}' > /tmp/test.c
      $ gcc -I ../include /tmp/test.c ../lib/libawka.a -lm -o /tmp/testprog
      $ /tmp/testprog
      nan nan inf -inf

So it seems that every other modern version of awk treats those
strings as numeric values.  Why should gawk be different?

Regards,
Andy