ruby-design-patterns

name	ruby-design-patterns
description	All 23 GoF design patterns with Ruby implementations from refactoring.guru. Use when designing or refactoring Ruby/Rails code and you need to apply or recognize a design pattern. Covers Creational (5), Structural (7), and Behavioral (11) patterns with Ruby code examples and Rails-specific applications.
disable-model-invocation	true

Ruby Design Patterns — Complete Reference

Source: https://refactoring.guru/design-patterns/ruby

Don't force patterns. Let them emerge from refactoring. Apply when you recognize the problem, not speculatively.

By Problem — Quick Lookup

Problem	Pattern	Category
Creating families of compatible objects	Abstract Factory	Creational
Building complex objects step by step	Builder	Creational
Subclass decides which object to create	Factory Method	Creational
Clone objects without coupling to class	Prototype	Creational
One instance globally	Singleton	Creational
Incompatible interfaces must work together	Adapter	Structural
Split abstraction from implementation	Bridge	Structural
Tree structures, treat parts and wholes uniformly	Composite	Structural
Add behavior without subclassing	Decorator	Structural
Simplify a complex subsystem	Facade	Structural
Share common state across many objects	Flyweight	Structural
Control access to an object	Proxy	Structural
Pass request through a handler chain	Chain of Responsibility	Behavioral
Encapsulate a request as an object	Command	Behavioral
Traverse a collection without exposing it	Iterator	Behavioral
Decouple communicating objects	Mediator	Behavioral
Save and restore object state	Memento	Behavioral
Notify many objects about events	Observer	Behavioral
Alter behavior when state changes	State	Behavioral
Swap algorithms at runtime	Strategy	Behavioral
Define algorithm skeleton, defer steps	Template Method	Behavioral
Add operations without modifying classes	Visitor	Behavioral

Ruby-Native Pattern Support

Pattern	Ruby built-in
Iterator	Enumerable, Enumerator
Observer	Observable module (stdlib)
Singleton	Singleton module (stdlib)
Decorator	Modules + prepend / extend
Strategy	Blocks / Procs / lambdas
Template Method	Inheritance + hook methods
Command	Proc / Method objects

Pattern Detail Files

• Creational Patterns (1–5) — Abstract Factory, Builder, Factory Method, Prototype, Singleton
• Structural Patterns (6–12) — Adapter, Bridge, Composite, Decorator, Facade, Flyweight, Proxy
• Behavioral Patterns (13–22) — Chain of Responsibility, Command, Iterator, Mediator, Memento, Observer, State, Strategy, Template Method, Visitor