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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Mon, 11 Jul 2011 11:41:41 -0600
Subject: Re: Property setter and lambda question
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On Mon, Jul 11, 2011 at 11:21 AM, Anthony Kong
<anthony.hw.kong@gmail.com> wrote:
> Awesome, Thomas. The trick only works if there is only=A0one=A0leading
> underscore in the=A0method=A0names.
> The following example works as I expected for the derived class B.
> class A(object):
> =A0 =A0 def __init__(self):
> =A0 =A0 =A0 =A0 self.__not_here =3D 1
> =A0 =A0 def _get_not_here(self):
> =A0 =A0 =A0 =A0 return self.__not_here
> =A0 =A0 def _set_not_here(self, v):
> =A0 =A0 =A0 =A0 print "I am called"
> =A0 =A0 =A0 =A0 self.__not_here =3D v
> =A0 =A0 not_here =3D property(lambda self: self._get_not_here(), lambda s=
elf, v:
> self._set_not_here(v))
> class B(A):
> =A0 =A0 def _set_not_here(self, v):
> =A0 =A0 =A0 =A0 print "version B"
> =A0 =A0 =A0 =A0 self.__not_here =3D v

It shouldn't.  You've still got the name __not_here used in both A and
B, so that the B version is setting a different attribute than the A
version (_B__not_here vs. _A__not_here).