Design Patterns & Principles - Strategy Pattern

This is a part of a blogpost series listing the design principles and pattern definitions.

The Strategy Pattern

- defines a family of algorithms, encapsulates each one, and makes them interchangeable. Strategy lets algorithm vary independently from clients that use it.
Following are few principles adhered in this pattern
  • Identify the aspect of your application that vary and separate them from what stays same.
  • Program to interface not to an implementation
  • Favor composition over inheritance

The example code for strategy pattern in Swift is available at my github repo.

courtesy: Head First Design Patterns

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