The singleton pattern
The singleton pattern is one of the most controversial patterns; many have accused it of being an "anti-pattern", a pattern that should be avoided, not promoted. In Python, if someone is using the singleton pattern, they're almost certainly doing something wrong, probably because they're coming from a more restrictive programming language.
So why discuss it at all? Singleton is one of the most famous of all design patterns. It is useful in overly object-oriented languages, and is a vital part of traditional object-oriented programming. More relevantly, the idea behind singleton is useful, even if we implement that idea in a totally different way in Python.
The basic idea behind the singleton pattern is to allow exactly one ...
Get Python: Journey from Novice to Expert now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
