Python's Multiple Inheritance: Picking which super() to call

python multiple-inheritance super
Name McChange picture Name McChange · Jan 8, 2013 · Viewed 23.7k times · Source

In Python, how do I pick which Parent's method to call? Say I want to call the parent ASDF2's __init__ method. Seems like I have to specify ASDF1 in the super()..? And if I want to call ASDF3's __init__, then I must specify ASDF2?!

>>> class ASDF(ASDF1, ASDF2, ASDF3):
    def __init__(self):
        super(ASDF1, self).__init__()


>>> ASDF()
ASDF2's __init__ happened
>>> class ASDF(ASDF1, ASDF2, ASDF3):
    def __init__(self):
        super(ASDF2, self).__init__()


>>> ASDF()
ASDF3's __init__ happened

Seems bonkers to me. What am I doing wrong?

Answer

Falmarri picture Falmarri · Jan 8, 2013

That's not what super() is for. Super basically picks one (or all) of its parents in a specific order. If you only want to call a single parent's method, do this

class ASDF(ASDF1, ASDF2, ASDF3):
    def __init__(self):
        ASDF2.__init__(self)

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