Weird behavior on dict attr

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Date	Tue, 10 Feb 2015 10:52:43 +0800
From	Shiyao Ma <i@introo.me>
To	python-list@python.org
Subject	Weird behavior on __dict__ attr
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Hi.

My context is a little hard to reproduce.

NS3 is a network simulation tool written in C++. I am using its Python binding.

So the class I am dealing with is from a .so file.

Say, I do the following:

%

import ns.network.Node as Node

# Node is a class
# it has a __dict__ attr

# Now I instantiate an instance of Node
n = Node()

# I checked, there is no __dict__ on 'n'
# but the following succeeds.

n.foobar = 3



My understanding is the foobar is stored in n.__dict__, but seemingly n has no __dict__.

So where does the foobar go?


TIA.



-- 
Shiyao Ma
http://introo.me

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Weird behavior on __dict__ attr Shiyao Ma <i@introo.me> - 2015-02-10 10:52 +0800
  Re: Weird behavior on __dict__ attr Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-02-10 19:00 +1100

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