Hi Jakob,

thanks for your reply. 

The proposed change is not supposed to change the semantics of resignalAs in any way (except limiting the argument to an exception instance, not a class).

We already have 3 resignalAs tests - is this ok? Pharo/Cuis are behind Squeak and as for VW I'm not familiar with their testing just yet.

The tests are green; well, after fixing my own contribution from last year (doubleOuterResignalAsTest) where I erroneously used a class as #resignalAs's argument - what a shame :) I'll definitely send a fix of this test to the Inbox.

> As so often, the breaking of applications that relied on the
> non-standard behavior may be an obstacle.
Yes indeed, that's a pain... theoretically as a workaround a class method could be added to create an instance and send it the instance side #resignalAs. However looking at its senders this method doesn't feel like frequently used :) (VA didn't even bother to implement it, at least in the version I have)

best,
~~~
^[^    Jaromir

Sent from Squeak Inbox Talk

On 2022-01-29T18:53:24+01:00, jakres+squeak at gmail.com wrote:

> Hi Jaromir,
> 
> We should start with a test case. I agree with your interpretation of
> the standard and see no harm in an inbox submission.
> Is there some ANSI Smalltalk test suite out there that could be shared
> between the dialects?
> 
> As so often, the breaking of applications that relied on the
> non-standard behavior may be an obstacle.
> 
> Kind regards,
> Jakob
> 
> Am Sa., 29. Jan. 2022 um 17:43 Uhr schrieb <mail at jaromir.net>:
> >
> > Hi all,
> >
> > I think Squeak's implementation of #resignalAs: is not following the ANSI specification precisely. Currently it reads:
> >
> > resignalAs: replacementException
> >
> >         signalContext resumeEvaluating: [replacementException signal]
> >
> > ANSI says:
> > "
> > The active exception action is aborted and the exception environment *and the evaluation context*
> > are restored to the same states that were in effect when the receiver was originally signaled.
> > This message (i.e. resignalAs:) causes the replacementException to be treated as if it had been originally
> > signaled instead of the receiver.
> > "
> >
> > This is very similar to #retry (or #retryUsing:) specification so I'd suggest the following implementation:
> >
> > resignalAs: replacementException
> >
> >         signalContext restartWithNewReceiver: replacementException
> >
> > The current implementation leads to building the new resignaled contexts on top of the previous signal contexts (and the resignalAs context itself) instead of simply *restarting* the previous signal context with the replacement exception as the new receiver. In my opinion the suggested implementation precisely follows the ANSI specification, and is consistent with current #retry and #retryUsing: implementation - compare:
> >
> > retryUsing: alternativeBlock
> >         "Abort an exception handler and evaluate a new block in place of the handler's protected block."
> >
> >         handlerContext restartWithNewReceiver: alternativeBlock
> >
> > Other dialects: Pharo and Cuis copied Squeak's but VW implemented resignalAs: to comply with ANSI precisely.
> >
> > One consideration: the current implementation allows "exception resignalAs: Error", i.e. allows Exception class as an argument but ANSI's version requires "exception resignalAs: Error new". All senders (there are just a few) in the base image seem use "Error new" anyway.
> >
> > My arguments for are: consistency, readability and less complexity (especially while debugging)
> >
> > What do you think? Inbox it?
> >
> > best,
> > ~~~
> > ^[^    Jaromir
> >
> > Sent from Squeak Inbox Talk
> >
> 
>