Analyzing Swift Protocol Extensions and C# Abstract Classes

This article explores the similarities and differences between Swift protocol extensions and C# abstract classes, written from the perspective of a developer experienced in both languages. It discusses how Swift lacks abstract classes but offers protocol extensions as a powerful alternative, inspired by WWDC15's Protocol Oriented Programming talk. The author compares how C# uses abstract classes to provide default implementations and define templates, versus Swift's protocol extensions that allow adding method implementations to protocols. The article examines abstraction mechanisms in both languages, including C# interfaces and class inheritance, and evaluates which approach is preferable for different scenarios. It provides insights into protocol-oriented versus class-oriented design, making it useful for developers working with Swift, C#, or both.