The curious behavior of integer objects

Robert Kern robert.kern at
Mon Jan 15 23:52:52 CET 2007

Jim B. Wilson wrote:
> Am I nuts? Or only profoundly confused? I expected the this little script
> to print "0":
> class foo(int): 
>   def __init__(self, value):
>     self = value & 0xF

That statement only rebinds the local name self to something else. It does not
modify the object at all or change the result of instantiating foo(). You need
to override __new__ to get the behavior that you want.

Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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