An Introduction to Swift
Until recently, writing an iPhone or iPad application meant working with Objective-C. Because of its unusual syntax, Objective-C is one of the most polarizing of programming languages—people tend to love it or hate it. At the World Wide Developer Conference in 2014, Apple changed all that by unveiling an alternative—a new language called Swift. Swift’s syntax is designed to be easily recognizable to programmers who are used to some of the more popular object-oriented programming languages like C++ and Java, therefore making it easier for them to start writing applications for iOS (and for Macs, since Swift is also fully supported as a development language on macOS). This appendix covers the parts of Swift that you’ll need to know in order to understand the example code in this book. We assume that you already have some programming experience and that you know what variables, functions, methods, and classes are. This appendix is neither a reference nor an exhaustive guide to the language—for that, there are numerous other resources, some of which are listed in Chapter 1.