Thanks to everyone for setting me straight!
I have been (erroneously!) assuming that any defined object would evaluate
to 'true'.
Thanks again.
Jonathan
----- Original Message -----
From: "Jens Vagelpohl" <[EMAIL PROTECTED]>
To: "[Zope] Mailing List" <[email protected]>
Sent: Tuesday, May 09, 2006 11:25 AM
Subject: Re: [Zope] A quick zope/python question
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On 9 May 2006, at 16:18, Jonathan wrote:
gc= <TransientObjectContainer at GarbageCollector>
GarbageCollector exists
I think I am misunderstanding something basic about python/zope here.
Why does a TOC object evaluate to false?
I think the basic misunderstanding is about what happens if you say...
if FOO: ...
Python will try to evaluate using steps such as looking for methods like
__nonzero__, __len__, etc, and you're not aware what these may evaluate
to given your object. A Folder, for example, evaluates to False when it
is empty.
You should use a different test to determine if that item exists.
jens
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