Popular recipes tagged "pattern" but not "oop"

Create on-the-fly class adapters with functools.partial (Python)

2014-05-29T18:48:28-07:00

Python recipe 578884 by Christoph Schueler (adapter, namedtuple, partial, pattern).

functools.partial could not only applied to functions it also works with classes. This opens some interesting perspectives, like on-the-fly creation of class adapters, as the following code illustrates.

Multiple unique class instances - a tentative design pattern (Python)

2013-02-23T14:11:44-08:00

Python recipe 578471 by Moritz Beber (design_pattern, pattern, unique).

Coming from Bioinformatics and having to deal with multiple objects with unique properties, like genes, proteins, and many more, I felt the need for a class that would always yield a unique instance based on a chosen identifier. This is because I always wanted the same instances whose attributes were filled with information and track them in various storage classes, like dictionaries, lists, etc. The code for the class lives over on github. Recently, I've added a lot of parallel-processing code so I adapted the pickling behaviour for this class to also yield existing instances. What follows is an example of how to use it and some discussion questions.

Maybe pattern (Python)

2010-07-21T11:08:11-07:00

Python recipe 577248 by Alan Franzoni (design, maybe, pattern). Revision 2.

An example Maybe pattern implementation for Python.

Flexible observer pattern implementation (Python)

2012-12-06T19:23:11-08:00

Python recipe 576962 by Glenn Eychaner (event, observer, pattern, publish, subscribe, threadsafe). Revision 16.

A simple, flexible, general-purpose observer pattern.

Observers can be callable objects or objects with a particular named method (handle_notify() by default). Events can be any object, and observers can select which events they are interested in receiving. Support for a number of different types of lightweight event objects is included.

Multicontext (e.g. asynchronous) inline execution framework using coroutines (Python)

2012-12-06T19:32:20-08:00

Python recipe 576965 by Glenn Eychaner (asynchronous, coroutine, decorator, generator, inline, nonblocking, pattern, thread). Revision 14.

A framework for executing inline code, contained in a generator, across multiple execution contexts, by pairing it with an executor that handles the context switching at each yield. An example of a generator which executes some iterations synchronously and some asynchronously is provided. The framework is general enough to be applied to many different coroutine situations.

Maintenance free Factory design pattern (Python)

2009-03-12T08:54:39-07:00

Python recipe 576687 by Akira Fora (design, factory, free, maintenance, pattern). Revision 3.

An implementation of the Factory design pattern that doesn't require maintenance when a new specialized subclass is added.