Book Image

Mastering Swift 3

Book Image

Mastering Swift 3

Overview of this book

Swift is the definitive language of Apple development today. It’s a vital part of any iOS and OS X developer’s skillset, helping them to build the most impressive and popular apps on the App Store—the sort of apps that are essential to iPhone and iPad users every day. With version 3.0, the Swift team have added new features to improve the development experience—making it easier to get the results you want and customers expect. Inside, you’ll find the key features of Swift 3.0 and quickly learn how to use the newest updates to your development advantage. From Objective-C interoperability to ARC, to closures and concurrency, this advanced Swift guide will develop your expertise and make you more fluent in this vital programming language. We give you in-depth knowledge of some of the most sophisticated elements of Swift development including protocol extensions, error-handling, design patterns, and concurrency, and guide you on how to use and apply them in your own projects. You'll see how even the most challenging design patterns and programming techniques can be used to write cleaner code and to build more performant iOS and OS X applications. By the end of this book, you’ll have a handle on effective design patterns and techniques, which means you’ll soon be writing better iOS and OS X applications with a new level of sophistication and control.
Table of Contents (23 chapters)
Mastering Swift 3
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Free Chapter
1
Taking the First Steps with Swift
2
Learning About Variables, Constants, Strings, and Operators

When not to use a custom subscript


As we have seen in this chapter, creating custom subscripts can really enhance our code; however, we should avoid overusing them or using them in a way that is not consistent with the standard subscript usage. The way to avoid overusing subscripts is to examine how subscripts are used in Swift's standard libraries.

Let's take a look at the following example:

class MyNames { 
  private var names:[String] = ["Jon", "Kim", "Kailey", "Kara"] 
  var number: Int { 
    get { 
      return names.count 
    } 
  } 
  subscript(add name: String) -> String { 
    names.append(name) 
    return name 
  } 
  subscript(index: Int) -> String { 
    get { 
      return names[index] 
    } 
    set { 
      names[index] = newValue 
    } 
  } 
} 

In the preceding example, within the MyNames class, we define an array of names that is used within our application. As an...