Sure, thanks for the insight--I more-or-less understand now. There
isn't an errorsw tag in the main read-eval-print loop, but various
hunks of code (defint.lisp, for example) have errorsw tags. I
don't know if there is a logical scheme for deciding when to catch and
ignore such errors; possibly the catch errorsw tags have been inserted
as needed to by-pass bugs.
Barton
maxima-bounces at math.utexas.edu wrote on 12/12/2008 08:30:34 AM:
> [image removed]
> Barton,
>
> I don't know the details of this mechanism, and whether it works
> correctly globally, but locally this makes sense: when errorsw is
> non-null, instead of giving the Divide by 0 error, simpexpt throws
> back to the tag errorsw.
>
> So it is not at all surprising that you get an error with a top-level
0^0.
>