Adapting Design Patterns to a Multi Paradigmatic World

How to adapt the classic GOF concepts to a multi paradigm language such as Python

Transcript

1. Adapting Design Patterns to a Multi Paradigmatic World Lia Nemeth
2. The Gang of Four (GoF) Published in 1994 Inspired by Christopher Alexander Patterns have: - Name - Problem - Solution - Consequences
3. These design patterns are not universal They are closely related to languages such as C++ and Java ¨The choice of programming language is important because it influences one's point of view." (GoF, 1994)
4. But knowing reusable design elements can still be useful And some patterns can be adapted for the multi-paradigmatic and dynamic nature of Python
5. Do not overdo it! Actual diagram from the book
6. Don't be object obsessed In 1994, Object Orientation was the shiny new thing and this influenced the GoF book
7. Strategy Pattern A behavioral pattern that enables selecting an algorithm at runtime
8. The Strategy pattern can be easily adapted to use functions if they are first class elements of the language.
10. Observer Pattern Very useful pattern for event handling
11. First class functions are again the key to make this pattern way simpler
15. Singleton is one of the most famous design patterns It's a class that allows a single object to be instantiated
16. Alex Martelli proposes Borg instead of singleton. It can have multiple objects, but they all share state
18. Some patterns like iterator and command are already embedded in the language
20. Conclusion Patterns can be useful, they are a great way to communicate an idea and getting to know them can bring good solutions to problems we face But always be cautious before blindly implementing them and think creatively on how they can be used
21. Thank you! Code at: github.com/lianemeth/design_patterns_talk