Bug in New Style Classes

[David MacQuigg]

I have what looks like a bug trying to generate new style classes with
a factory function.

class Animal(object): pass
class Mammal(Animal): pass

def newAnimal(bases=(Animal,), dict={}):
    class C(object): pass
    C.__bases__ = bases
    dict['_count'] = 0
    C.__dict__ = dict
    return C

Canine = newAnimal((Mammal,))
TypeError: __bases__ assignment: 'Mammal' deallocator differs from
'object'

If I remove the 'object' from the class C(object) statement, then I
get a different, equally puzzling error message:

TypeError: __bases__ items must be classes

The function works only if I remove 'object' from all base classes.

-- Dave

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* David MacQuigg, PhD              * email:  dmq at gain.com      *  *
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* Analog Design Methodologies                                  *  *  *
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