Book Image

Swift 3 Object-Oriented Programming - Second Edition

By : Gaston C. Hillar
Book Image

Swift 3 Object-Oriented Programming - Second Edition

By: Gaston C. Hillar

Overview of this book

Swift has quickly become one of the most-liked languages and developers’ de-facto choice when building applications that target iOS and macOS. In the new version, the Swift team wants to take its adoption to the next level by making it available for new platforms and audiences. This book introduces the object-oriented paradigm and its implementation in the Swift 3 programming language to help you understand how real-world objects can become part of fundamental reusable elements in the code. This book is developed with XCode 8.x and covers all the enhancements included in Swift 3.0. In addition, we teach you to run most of the examples with the Swift REPL available on macOS and Linux, and with a Web-based Swift sandbox developed by IBM capable of running on any web browser, including Windows and mobile devices. You will organize data in blueprints that generate instances. You’ll work with examples so you understand how to encapsulate and hide data by working with properties and access control. Then, you’ll get to grips with complex scenarios where you use instances that belong to more than one blueprint. You’ll discover the power of contract programming and parametric polymorphism. You’ll combine generic code with inheritance and multiple inheritance. Later, you’ll see how to combine functional programming with object-oriented programming and find out how to refactor your existing code for easy maintenance.
Table of Contents (17 chapters)
Swift 3 ObjectOriented Programming - Second Edition
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Overriding and overloading methods


Swift allows us to define a method with the same name many times with different arguments. This feature is known as method overloading. In some cases, as in our previous example, we can overload the designated initializer. However, it is very important to mention that a similar effect might be achieved with optional parameters or default values for specific arguments.

For example, we can take advantage of method overloading to define multiple versions of the bark method that we have to define in the Dog class. However, it is very important to avoid code duplication when we overload methods.

Sometimes, we define a method in a class, and we know that a subclass might need to provide a different version of the method. When a subclass provides a different implementation of the method defined in a superclass, with the same name, arguments, and return type, we say that we are overriding a method. When we override a method, the implementation in the subclass overwrites...