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

Selecting a closure based on results


In the final example, we will pass two closures to a method, and then, depending on some logic, one, or possibly both, of the closures will be executed. Generally, one of the closures is called if the method was successfully executed and the other closure is called if the method failed.

Let's start off by creating a class that will contain a method that will accept two closures and then execute one of the closures based on the defined logic. We will name this class TestClass. Here is the code for the TestClass class:

class TestClass { 
  typealias ResultsClosure = ((String) -> Void) 
 
  func isGreater(numOne: Int, numTwo:Int, successHandler:      ResultsClosure, failureHandler: ResultsClosure) { 
    if numOne > numTwo { 
      successHandler("\(numOne) is greater than \(numTwo)") 
    } 
    else { 
      failureHandler("\(numOne) is not greater than \(numTwo)") 
    } 
 
  } 
} 

We...