[Python-Dev] PEP 343 rewrite complete

Eric Nieuwland eric.nieuwland at xs4all.nl
Thu Jun 2 22:16:42 CEST 2005


On 2 jun 2005, at 22:12, Phillip J. Eby wrote:

> At 10:04 PM 6/2/2005 +0200, Eric Nieuwland wrote:
>> I was thinking about 'try EXPR [as VAR]:' as a 'try' that handles 
>> uncaught exceptions by forwarding it to EXPR's __exit__ method. No 
>> confusion with me.
>
> No doubt.  However, it's not obvious what happens to an exception in 
> EXPR; surely it can't be passed to EXPR's __exit__ method.  So, is it 
> handled by the try, or does it pass out of the block?  Whichever 
> answer you give, there is somebody who will think the opposite.  And 
> this is precisely the ambiguity I've been talking about.
>
> In contrast, a 'with' unmixed with 'try' is absolutely unambiguous as 
> to which except: clauses handle what exceptions where.

<slap forehead> I never thought of that! Now I see what you mean.
I could only save my idea by stating "the scope of 'try' only starts 
after the ':'", but that seems too artificial.

--eric



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