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 10. Using Optional Types

When I first started using Swift, the concept that I had the most trouble with was optional types. Coming from an Objective-C, C, Java, and Python background, I was able to relate to most of Swift's features to how things worked in one of the other languages that I knew, but optionals were different. There really was nothing like optionals in the other languages that I used, so it took a lot of reading to fully understand them. While I briefly covered optionals in Chapter 2, Learning about Variables, Constants, Strings, and Operators, which gave enough of an overview to get started with, we need to cover a lot more information to really understand what optionals are, how to properly use them, and why they are so important in the Swift language.

In this chapter, we will cover the following topics:

  • An introduction to optional types

  • The need for optional types in Swift

  • Unwrapping an optional

  • Optional binding

  • Optional chaining