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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 16 Dec 2011 09:23:47 -0700
Subject: Re: Class: @property -> .__dict__
To: Peter Otten <__peter__@web.de>
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On Fri, Dec 16, 2011 at 2:32 AM, Peter Otten <__peter__@web.de> wrote:
> Ulrich wrote:
>
>> if I replace it to
>> def attributelist(self):
>> =A0 =A0 =A0 =A0 =A0# find all attributes to the class that are of type n=
umpy
>> arrays:
>> =A0 =A0 =A0 =A0 =A0return [attr for attr in dir(self) if
>> isinstance(getattr(self, attr), numpy.ndarray)]
>>
>> it crashes going into some kind of endless loop.
>>
>> Do you happen to have any idea?
>
> dir(self) finds an attribute named "attributelist", getattr(self,
> "attributelist") then tries to calculate the value of that attribute,
> invokes dir(self) which finds an attribute named "attributelist" and so o=
n
> ad infinitum or the stack overflows. Try (untested)
>
> @property
> def attributelist(self):
> =A0 =A0return [attr for attr in dir(self) if attr !=3D "attributelist" an=
d
> =A0 =A0 =A0 =A0 =A0 =A0isinstance(getattr(self, attr), numpy.ndarray)]
>
> to avoid the infinite recursion.

Or remove attributelist from the class (it feels more like a generic
function than a class property to me) or make it a method instead of a
property.