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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Mon, 11 Jul 2011 11:35:05 -0600
Subject: Re: Property setter and lambda question
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On Mon, Jul 11, 2011 at 10:53 AM, Anthony Kong
<anthony.hw.kong@gmail.com> wrote:
> Thanks again for your input, Thomas.
> I normally prefer
> not_here =3D property(lambda self: self.__get_not_here(), lambda self,=A0=
v:
> self.__set_not_here(v))
> than
> not_here =3D property(__get_not_here, __set_not_here)
> Because it allows me to have a pair getter/setter (when there is a need f=
or
> it). Use of lambda there is ensure derived class of A can provide their
> custom version of getter/setter.

The .setter convenience method also makes it a bit easier for derived
classes to modify getters and setters:

class Base(object):

    def get_my_property(self):
        return self._my_property

    def set_my_property(self, value):
        self._my_property =3D value

    my_property =3D property(get_my_property, set_my_property)


class Derived(Base):

    def set_my_property(self, value):
        super(Derived, self).set_my_property(convert(value))

    my_property =3D Base.my_property.setter(set_my_property)