Hi Aleksander,

Thanks for your response.  And thanks to Benji, too, for 
replying with the informative link.  More below...

> From zope3-users On Behalf Of Aleksander Kowalczyk
> On 4/12/07, Giovannetti, Mark <[EMAIL PROTECTED]> wrote:
>       Hi list,
>       Hope everyone's having a splendid day/evening/whatever.
>       I've encountered a strange error.  I have two chunks
>       of nearly identical code below.  The only difference
>       is the first "if" statement.  One has: 
>           if context:
>       the other has:
>           if context is not None
>       The first fails to be true even if context is not None.
>       This can be seen by the output from the logs showing the
>       context variable as: 
> Possibly a context is a container-like object.
> For containers operation
> "if context" is equal to "if len(context) > 0".  So even if 
> context is not None, it still may be False if the container 
> does not contain any elements. 

This occurred to me at about the same time I read your message.
The context is indeed a container (which happened to be empty),
thus the false evaluation as you suggest.

Another nugget of useful python/zope programming knowledge!

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