Book Image

Mastering Swift 2

By : Jon Hoffman
Book Image

Mastering Swift 2

By: Jon Hoffman

Overview of this book

<p><span id="description" class="sugar_field">At their Worldwide Developer’s conference (WWDC) in 2015, Apple announced Swift 2, a major update to the innovative programming language they first unveiled to the world the year before. Swift 2 features exciting enhancements to the original iteration of Swift, acting, as Apple put it themselves as “a successor to the C and Objective-C languages.” – This book demonstrates how to get the most from these new features, and gives you the skills and knowledge you need to develop dynamic iOS and OS X applications.<br /> </span></p> <p><span id="description" class="sugar_field">Learn how to harness the newest features of Swift 2 todevelop advanced applications on a wide range of platforms with this cutting-edge development guide. Exploring and demonstrating how to tackle advanced topics such as Objective-C interoperability, ARC, closures, and concurrency, you’ll develop your Swift expertise and become even more fluent in this vital and innovative language. With examples that demonstrate how to put the concepts into practice, and design patterns and best practices, you’ll be writing better iOS and OSX applications in with a new level of sophistication and control.</span></p>
Table of Contents (24 chapters)
Mastering Swift 2
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
Index

Chapter 9. Custom Subscripting

Custom subscripts were added to Objective-C in 2012. At that time, Chris Lattner was already 2 years into developing Swift and like other good features of Objective-C, subscripts became a part of the Swift language. I did not frequently use custom subscripts in Objective-C, but I did know that they were a part of the language when I needed them. Subscripts in Swift seem, to me, to be a more natural part of the language, possibly because they were part of the language when it was released and not added in later.

In this chapter, you will learn the following topics:

  • What are custom subscripts

  • How to add custom subscripts to classes, structures, or enums

  • How to create read/write and read-only subscripts

  • How to use external names without custom subscripts

  • How to use multidimensional subscripts