[Python-Dev] 2.2=>2.3 object.__setattr__(cls,attr,value)

David Eppstein eppstein at ics.uci.edu
Tue Nov 18 22:23:59 EST 2003

In 2.2 I was able to call object.__setattr__(cls,attr,value)
where cls is a new-style type (first argument of a classmethod),
and attr and value are the name and value of a class attribute I want to 
create programmatically.  I just upgraded to 2.3 but now when I try it I 

>>> class foo(object):pass
>>> object.__setattr__(foo,'foo',None)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: can't apply this __setattr__ to type object

Instead I apparently have to call
>>> type(foo).__setattr__(foo,'foo',None)

Anyway, my question: no harm done here because this was in undeployed 
code and I've found a workaround, but shouldn't this have at least been 
mentioned in "What's New in Python 2.3"?  Or maybe this is one of the 
some-other-change-with-far-reaching-consequences things that was 
mentioned and I just don't see the connection?

David Eppstein                      http://www.ics.uci.edu/~eppstein/
Univ. of California, Irvine, School of Information & Computer Science

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