Exception handling question

Roel Wuyts wuyts at iam.unibe.ch
Tue Aug 5 07:51:37 UTC 2003


Aha.
So who would be willing to change it? I don't feel comfortable with 
doing it myself, unless there are enough unit tests around...

On Monday, Aug 4, 2003, at 19:00 Europe/Zurich, Anthony Hannan wrote:

> Roel Wuyts <wuyts at iam.unibe.ch> wrote:
>>> The most important point however is that Exception DOES NOT
>>> handle Halt (in spite of the fact that Halt is a subclass of
>>> Exception.)
>> Can somebody motivate this decision (or whether it is an unintentional
>> bug)?
>
> I'm not the author but I believe the reason is so "self halt" will
> always halt and not be accidentally handled by a earlier Error handler.
> The better solution is probably to not make Halt a subclass of Error 
> but
> just a direct subclass of Exception.
>
> By the way, UnhandledError is a new exception class that gets raised in
> Error defaultAction when an Error is not handled.  If UnhandledError is
> also not handled then its defaultAction is to open the debugger on the
> original exception.  This extra level of indirection allows the thread
> to control debugger opening.  This was implemented to support a better
> way to handle exceptions while stepping through code in the debugger
> itself.
>
> Cheers,
> Anthony
>
>
Roel Wuyts                                                   Software 
Composition Group
roel.wuyts at iam.unibe.ch                       University of Bern, 
Switzerland
http://www.iam.unibe.ch/~wuyts/
Board Member of the European Smalltalk User Group: www.esug.org



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