[Zope-dev] ZEO cache instrumentation -- any takers?

Chris McDonough chrism@zope.com
04 Oct 2002 08:42:05 -0400


On Fri, 2002-10-04 at 08:21, Guido van Rossum wrote:
> > What would be nice is a way to define in Python a kind of exception
> > that is not caught by bare "except:" statements but only by "except
> > SpecificClass:" statements.  Not quite an uncatchable exception, but
> > one that is caught only by except statements that name it.
> 
> I'm skeptical about this one.  Can you explain the use case?

I am too.  ;-)

Zope (for better or worse) uses the same machinery that users use in
scripts and templates to deal with exceptional conditions
(ConflictError, Unauthorized, etc). It should not be possible for users
to catch these kinds of errors in Python Scripts and/or TAL. The two
"exception domains" should really be divorced in some way.

How about "goto"? ;-)  Just kidding.
> 
> You can probably fake this to a large extent by using "except
> Exception:" instead of "except:" everywhere; then you can raise an
> exception that does not inherit from Exception.

This is probably the thing to do.

- C