[Python-Dev] py3k: TypeError: object.__init__() takes no parameters
nick at craig-wood.com
Fri Jan 16 17:53:52 CET 2009
Terry Reedy <tjreedy at udel.edu> wrote:
> Nick Craig-Wood wrote:
> > I've noticed with latest python 3.1 checkout (68631) if I have this
> > object hierarchy with a default __init__ in the superclass to be used
> > by the subclasses which don't necessarily need an __init__ it blows up
> > with a TypeError.
> > class Field(object):
> object is default baseclass, hence not needed
Agreed, but I wanted the code to run with py < 3 also!
> > def __init__(self, data):
> > """Default init for the subclasses"""
> > print("init class=%r, self=%r" % (self.__class__.__name__, self))
> > super(Field, self).__init__(data)
> This line is the problem: remove it and I believe all is fine.
> Since object()s are immutable, its init cannot do anything as far as I
> know. Deleting this is effectively what you did below.
Yes you are absolutely right - that super is never needed. I don't
know what I was thinking of! Without that the problem disappears.
> Perhaps 2.5's object.__init__ just swallowed all args, thus hiding bogus
Yes it did which is the fundamental difference in behaviour between
py2 and py3 as far as I can see.
> Eliminate bad call.
(Bashes head against wall!)
Nick Craig-Wood <nick at craig-wood.com> -- http://www.craig-wood.com/nick
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