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From: Dave Angel <davea@davea.name>
Subject: Re:singleton ... again
Date: Wed, 12 Feb 2014 00:48:51 -0500 (EST)
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Xref: csiph.com comp.lang.python:65999

 Asaf Las <roegltd@gmail.com> Wrote in message:
> playing a bit with subject. 
> 
> pros and cons of this approach? did i create bicycle again? :-)
> 
> class myclass(object):
>     class_instance = None
>     
>     def __new__(cls, *args, **kwargs):
>         if myclass.class_instance == None:
>             return object.__new__(cls)
>         return myclass.class_instance
> 
>     def __init__(self, some):
>         if self.__class__.class_instance == None: # init blocker 
>             self.__class__.class_instance = self
>             self.member = some
>     
>     def __del__(self):
>         self.__class__.class_instance = None
>     
> one_class = myclass(1)
> print(id(one_class), one_class.member )
> 
> two_class = myclass(2)
> print(id(two_class), two_class.member)
> 
> 

Perhaps if you would state your actual goal,  we could judge
 whether this code is an effective way to accomplish
 it.


-- 
DaveA