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Date: Thu, 23 Jan 2014 14:36:17 +0100
From: Johannes Schneider <johannes.schneider@galileo-press.de>
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Subject: Re: SIngleton from __defaults__
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On 22.01.2014 20:18, Ned Batchelder wrote:
> On 1/22/14 11:37 AM, Asaf Las wrote:
> Chris is right here, too: modules are themselves singletons, no matter
> how many times you import them, they are only executed once, and the
> same module object is provided for each import.

I'm not sure, if this is the whole truth.

think about this example:

cat bla.py
a = 10

cat foo.py
from bla import a

def stuff():
         return a

cat bar.py
from foo import stuff
print stuff()
a = 5
print stuff()

from bla import *
print a

python bar.py
10
10
10

here the a is coming from bla and is known in the global namespace. But 
the value differs in stuff() and before/after the import statement. So 
the instance of the module differs -> it cannot be a singelton.

bg,
Johannes

-- 
Johannes Schneider
Webentwicklung
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