Book Image

Swift Protocol-Oriented Programming - Fourth Edition

By : Jon Hoffman
Book Image

Swift Protocol-Oriented Programming - Fourth Edition

By: Jon Hoffman

Overview of this book

Protocol-oriented programming is an incredibly powerful concept at the heart of Swift's design. Swift's standard library was developed using POP techniques, generics, and first-class value semantics; therefore, it is important for every Swift developer to understand these core concepts and take advantage of them. The fourth edition of this book is improved and updated to the latest version of the Swift programming language. This book will help you understand what protocol-oriented programming is all about and how it is different from other programming paradigms such as object-oriented programming. This book covers topics such as generics, Copy-On-Write, extensions, and of course protocols. It also demonstrates how to use protocol-oriented programming techniques via real-world use cases. By the end of this book, you will know how to use protocol-oriented programming techniques to build powerful and practical applications.
Table of Contents (11 chapters)

Using value and reference types

In this chapter, we implemented the vehicle types as structures, which are value types. We also mentioned that it may be preferable to implement these types as reference types. The reason we say this is that the instance of the vehicle types represent a single vehicle in our game and any time something happens to that instance, such as taking damage from another vehicle, we would like that change to be persisted.

When we pass an instance of a value type to another part of our code, we are passing a copy of that instance and not the instance itself. This can cause problems when we want to persist changes that are applied to our types. Let's look at this problem with some code. We will start off by creating a function that will apply damage to a vehicle type when it is implemented as a reference type, just like we did with the object-oriented...