Hi Klaus,

Klaus D. Witzel wrote:
> Nah, the result has nothing to do with #on:do: resuming with 1, you better
> try
> 
> [('abc' + 1) + 1]
>    on: MessageNotUnderstood
>    do: [:e | e resume: -1]
> 
> which still says 2. This because someone, behind you back, put #asNumber
> arithmethic into ByteString ... now this attempts (Number readFrom: 'abc')
> which gives 0 for your +1 +1 and so 2.
> 
> You may want to start DNU testing with ('abc' break; + 1) and then see
> where it goes.

Hmm... I think something is not right or at the very least the semantics 
are subtly different than I expect.

VisualWorks:
[Object new blah + 1]
   on: MessageNotUnderstood
   do: [:e | e resume: 1]  " = 2 "

[MessageNotUnderstood signal + 1]
   on: MessageNotUnderstood
   do: [:e | e resume: 1] " = 2 "

Squeak:
[Object new blah + 1]
   on: MessageNotUnderstood
   do: [:e | e resume: 1]  " infinite recursion!!! "

[MessageNotUnderstood signal + 1]
   on: MessageNotUnderstood
   do: [:e | e resume: 1] " = 2 "


If I look at doesNotUnderstand: in both I see that in VW the resumed 
value is returned. In Squeak is is not... surely this can't be right?

As for my problem, I think a simpler solution is to pass an 
adaptor/proxy object to the block rather than the tag itself. This 
adaptor can then marshal behaviour such that it will act as a message 
eating null if it receives an MNU from the tag it's looking after.

Thanks,
Zulq.