[Zope3-Users] iteration over non sequence in wcdwz3 example

[Baiju M]

ilflaminio at virgilio.it wrote:

> I'm reading Web Component Development with Zope 3. The line
>
>>>> from
>>>
> worldcookery.recipe import Recipe
> gives me this error:
> Traceback (most
> recent call last):
> File "<interactive input>", line 1, in ?
> File "C:
> \Programmi\Python24\lib\site-packages\worldcookery\recipe.py", line 4,
> in ?
> class Recipe:
> File "C:\programmi\Python24\Lib\site-
> packages\zope\interface\advice.py", line 132, in advise
> return
> callback(newClass)
> File "C:\programmi\Python24\Lib\site-
> packages\zope\interface\declarations.py", line 485, in
> _implements_advice
> classImplements(cls, *interfaces)
> File "C:
> \programmi\Python24\Lib\site-packages\zope\interface\declarations.py",
> line 462, in classImplements
> spec.declared += tuple(_normalizeargs
> (interfaces))
> File "C:\programmi\Python24\Lib\site-
> packages\zope\interface\declarations.py", line 1371, in _normalizeargs
> _normalizeargs(v, output)
> File "C:\programmi\Python24\Lib\site-
> packages\zope\interface\declarations.py", line 1370, in _normalizeargs
> for v in sequence:
> TypeError: Error when calling the metaclass
> bases
> iteration over non-sequence
>
> Can anyone say to me what this
> message means? I use zope 3.3.1, python 2.4.4, win XP.

While running, make sure that your interface (IRecipe or whatever) 
really inherit from zope.interface.Interface

Regards,
Baiju M