Python new-style classes and the super() function
12 July 2008
I've never really understood the impact of new-style Python classes and what it means to your syntax until now. With new-style classes you can use the
super() builtin, otherwise you can't. This works for new-style classes:
class Farm(object): def __init__(self): pass class Barn(Farm): def __init__(self): super(Barn, self).__init__()
If you want to do the same for old-style classes you simply can't use
super() so you'll have to do this:
class Farm: def __init__(self): pass class Barn(Farm): def __init__(self): Farm.__init__(self)
Strange that I've never realised this before. The reason I did now was that I had to back-port some code into Zope 2.7 which doesn't support setting security on new-style classes.
Now I need to do some reading on new-style classes because clearly I haven't understood it all.