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[Python-Dev] unsubscriptable vs object does not support indexing

Steven D'Aprano steve at pearwood.info
Thu Sep 24 01:33:08 CEST 2009 
On Thu, 24 Sep 2009 06:47:41 am Dino Viehland wrote:
> > So I am +1 on unified the message and +1 on using the "does not
> > support indexing" one.
>
> I'd be +1 on the unified message as well - but it seems what that
> message should be may be contentious (and quite a bike shed
> discussion at that). The bug David linked to
> (http://bugs.python.org/issue5760) has a preference for subscript
> because that's what's used elsewhere in the language.

For what it's worth, "unsubscriptable object" seems to me to be 
mysterious to many newbies, and even a few non-newbies. It took me 
something like seven years of coding to stop reading it 
as "unscriptable object", and I'm sure I won't be the only one.

As far as I can see, in practice, people talk about obj[i] as the item 
at index i, not the item at subscript i -- the term "subscript" in this 
context seems to be rare to non-existent except for the error message.



-- 
Steven D'Aprano
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