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From: Devin Jeanpierre <jeanpierreda@gmail.com>
Date: Mon, 24 Sep 2012 15:22:07 -0400
Subject: Re: Java singletonMap in Python
To: Mark Lawrence <breamoreboy@yahoo.co.uk>
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On Sun, Sep 23, 2012 at 7:14 PM, Mark Lawrence <breamoreboy@yahoo.co.uk> wrote:
> 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

The word "singleton" usually means "thing with only one item". For
example, {a} is a singleton set containing only a, and with matrices,
any dimension of size one is called a singleton dimension, and so on.
In this case, a singleton map is a map with only one key-value pair,
such as {a:b}.

The singleton design antipattern is not relevant here.

-- Devin