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From: Peter Otten <__peter__@web.de>
Subject: Re: Trying to learn about metaclasses
Date: Mon, 25 Jul 2011 18:01:58 +0200
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:10284

Steven W. Orr wrote:

> I have been doing a lot of reading. I'm starting to get it. I think it's
> really cool as well as dangerous, but I plan on being respectful of the
> construct. I found a web page that I found quite readable.
> 
> http://cleverdevil.org/computing/78/
> 
> So, I tried to run the example code (below), and I get AttributeError. If
> someone can get me over this hump, I'd be grateful. It complains that
> Person has no _fields attribute, but the print hello I have in
> EnforcerMeta doesn't happen either. Am I doing something wrong?
> 
> I'm running python 2.6.2
> 
> Here's the error:
> 
> 585 > ./meta1.py
> Traceback (most recent call last):
>    File "./meta1.py", line 38, in <module>
>      swo.name = 'swo'
>    File "./meta1.py", line 27, in __setattr__
>      if key in self._fields:
> AttributeError: 'Person' object has no attribute '_fields'

> And here's the code:
> 
> class EnforcerMeta(type):
>      def __init(cls, name, bases, ns):

You misspelt __init__()