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From: Mark Lawrence <breamoreboy@yahoo.co.uk>
Subject: Java singletonMap in Python
Date: Mon, 24 Sep 2012 00:14:23 +0100
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Xref: csiph.com comp.lang.python:29873

Purely for fun I've been porting some code to Python and came across the 
singletonMap[1].  I'm aware that there are loads of recipes on the web 
for both singletons e.g.[2] and immutable dictionaries e.g.[3].  I was 
wondering how to combine any of the recipes to produce the best 
implementation, where to me best means cleanest and hence most 
maintainable.  I then managed to muddy the waters for myself by 
recalling the Alex Martelli Borg pattern[4].  Possibly or even probably 
the latter is irrelevant, but I'm still curious to know how you'd code 
this beast.

First prize for the best solution is a night out with me, no guesses 
what the second prize is :)

[1]http://docs.oracle.com/javase/1.4.2/docs/api/java/util/Collections.html
[2]http://stackoverflow.com/questions/31875/is-there-a-simple-elegant-way-to-define-singletons-in-python
[3]http://code.activestate.com/recipes/498072-implementing-an-immutable-dictionary/
[4]http://code.activestate.com/recipes/66531-singleton-we-dont-need-no-stinkin-singleton-the-bo/
-- 
Cheers.

Mark Lawrence.