On 2 April 2013 14:27, Fabian PyDEV <py...@hotmail.com> wrote:
> Hi All,
>
> I have a question.
>
> Let says I have the following two classes:
>
> class Base(object):
>         __mylist__ = ["value1", "value2"]
>
>         def somemethod(self):
>                 pass
>
>
> class Derived(Base):
>         __mylist__ = ["value3", "value4"]
>
>         def anothermethod(self):
>                 pass
>
>
>
>
> what I would like to accomplish is that the class Derived has the member 
> __mylist__ extended or merged as ["value1", "value2", "value3", "value4"].
>
> Is there anyway I could accomplish this?
>
> I was thinking on accomplishing this as follows:
>
>
> class Derived(Base):
>         __mylist__ = Base.__mylist__ + ["value3", "value4"]
>
>         def anothermethod(self):
>                 pass
>
>
> Is there a better way? Perhaps a decorator?

class Base(object):

        mybits = ["value1", "value2"]

        @classmethod
        def mylist(cls):
                return sum((getattr(p, 'mybits', []) for p in cls.mro()[::-1]), 
[])


class Derived(Base):

        mybits = ["value3", "value4"]


class FurtherDerived(Derived):

        mybits = ["value5"]


>>> Derived.mylist()
['value1', 'value2', 'value3', 'value4']
>>> FurtherDerived.mylist()
['value1', 'value2', 'value3', 'value4', 'value5']

HTH

-- 
Arnaud
-- 
http://mail.python.org/mailman/listinfo/python-list

Reply via email to