Book Image

Mastering Swift 3 - Linux

By : Jon Hoffman
Book Image

Mastering Swift 3 - Linux

By: Jon Hoffman

Overview of this book

Swift is a modern, fast, and safe programming language created by Apple. Writing Swift is interactive and fun, the syntax is concise yet expressive, and the code runs lightning-fast. Swift’s move to open source has been embraced with open arms and has seen increased adoption in the Linux platform. Our book will introduce you to the Swift language, further delving into all the key concepts you need to create applications for desktop, server, and embedded Linux platforms. We will teach you the best practices to design an application with Swift 3 via design patterns and Protocol-Oriented Programming. Further on, you will learn how to catch and respond to errors within your application. When you have gained a strong knowledge of using Swift in Linux, we’ll show you how to build IoT and robotic projects using Swift on single board computers. By the end of the book, you will have a solid understanding of the Swift Language with Linux and will be able to create your own applications with ease.
Table of Contents (24 chapters)
Mastering Swift 3 - Linux
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
2
Learning About Variables, Constants, Strings, and Operators

Read-only custom subscripts


We can also make the subscript read-only by either not declaring a setter method within the subscript or by not implicitly declaring a getter or setter method. The following code shows how to declare a read-only property by not declaring a setter method:

//No getter/setters implicitly declared 
subscript(index: Int) ->String { 
  return names[index] 
} 

The following example shows how to declare a read-only property by only declaring a getter method:

//Declaring only a getter 
subscript(index: Int) ->String { 
  get { 
    return names[index] 
  } 
} 

In the first example, we do not define either a getter or setter method; therefore, Swift sets the subscript as read-only and the code acts as if it was in a getter definition. In the second example, we specifically set the code in a getter definition. Both examples are valid read-only subscripts.