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Date: Mon, 21 Nov 2011 14:44:34 +0000
From: Andrea Crotti <andrea.crotti.0@gmail.com>
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Subject: decorators and closures
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:16012

With one colleague I discovered that the decorator code is always 
executed, every time I call
a nested function:

def dec(fn):
     print("In decorator")
     def _dec():
         fn()

     return _dec

def nested():
     @dec
     def fun():
         print("here")

nested()
nested()

Will give:
In decorator
In decorator

So we were wondering, would the interpreter be able to optimize this 
somehow?
I was betting it's not possible, but I'm I would like to be wrong :)