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Date: Thu, 23 Jan 2014 03:18:57 +1100
Subject: Re: SIngleton from __defaults__
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:64508

On Thu, Jan 23, 2014 at 3:07 AM, Asaf Las <roegltd@gmail.com> wrote:
> is it possible to create singleton using construct below :
>
> def singleton_provider(x = [None]):
>     if singleton_provider.__defaults__[0][0] == None:
>         singleton_provider.__defaults__[0][0] = SomeClass()
>     return singleton_provider.__defaults__[0][0]
>

Why not simply:

def get_singleton(x = SomeClass()):
    return x

Or even:

singleton = SomeClass()

? Neither of the above provides anything above the last one, except
for late creation.

ChrisA