Book Image

Swift 3 New Features

By : Keith Elliott
Book Image

Swift 3 New Features

By: Keith Elliott

Overview of this book

Since Swift was introduced by Apple in WWDC 2015, it has gone on to become one of the most beloved languages to develop iOS applications with. In the new version, the Swift team aimed to take its adoption to the next level by making it available for new platforms and audiences. This book will very quickly get you up to speed and productive with Swift 3. You will begin by understanding the process of submitting new feature requests for future versions of Swift. Swift 3 allows you to develop and run your applications on a Linux machine. Using this feature, you will write your first Linux application using the debugger in Linux. Using Swift migrator, you will initiate a conversion from Swift 2.2 to Swift 3. Further on, you will learn how to interact with Cocoa libraries when importing Objective C to Swift. You will explore the function and operator changes new to Swift 3, followed by Collection and Closure changes. You will also see the changes in Swift 3 that allow you write tests easier with XCTest and debug your running code better with new formats as well. Finally, you will have a running server written completely in Swift on a Linux box. By the end of the book, you will know everything you need to know to dive into Swift 3 and build successful projects.
Table of Contents (16 chapters)
Swift 3 New Features
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
5
Function and Operator Changes – New Ways to Get Things Done

Collection and sequence type changes


Let's begin our discussion with Swift 3 changes to Collection and Sequence types. Some of the changes are subtle and others are bound to require a decent amount of refactoring to your custom implementations. Swift provides three main collection types for warehousing your values: arrays, dictionaries, and sets. Arrays allow you to store values in an ordered list. Dictionaries provide unordered key-value storage for your data. Finally, sets provide an unordered list of unique values (that is, no duplicates allowed).

Lazy FlatMap for sequence of optional [SE-0008]

Arrays, dictionaries, and sets are implemented as generic types in Swift. They each implement the new Collection protocol, which implements the Sequence protocol. Along this path from top-level type to Sequence protocol, you will find various other protocols that are also implemented in this inheritance chain. For our discussion on flatMap and lazy flatMap changes, I want to focus on Sequences.

Sequences...