multiple inheritance

[Thomas Girod]

Hi.

I think I'm missing something about multiple inheritance in python.

I've got this code.

class Foo:
    def __init__(self):
        self.x = "defined by foo"
        self.foo = None

class Bar:
    def __init__(self):
        self.x = "defined by bar"
        self.bar = None

class Foobar(Foo,Bar):
    pass

fb = Foobar()
print fb.x
print fb.__dict__

which returns :

>>>
defined by foo
{'x': 'defined by foo', 'foo': None}

So I guess not defining __init__ in my class Foobar will call __init__
from my superclass Foo. Also __dict__ doesn't show an attribute
'bar':None so I guess Bar.__init__ is not called at all.

I would like to have a subclass with all attributes from superclasses
defined, and only the attribute from the first when there is conflict
(i.e. in this case, Foobar would be like this but with bar:None)

I tried this :

class Foobar(Foo,Bar):
    def __init__(self):
        Foo.__init__(self)
        Bar.__init__(self)

>>>
defined by bar
{'x': 'defined by bar', 'foo': None, 'bar': None}

Here I have all I want, except the value of 'x' comes from the 'Bar'
superclass rather than Foo. So, to have what I want, I would have to
invert the two calls to __init__ in order to have the right x value.

What I find awkward here is that the order of __init__ calls matters,
rather than the order of the classes in the class declaration.

Do you have any ideas of a way to get this multiple inheritance thing
solved without having to do those __init__ calls ?

Thomas