Professional Swift

9

Bridging Swift and Objective-C

WHAT'S IN THIS CHAPTER

• Organizing Swift code with namespaces
• Packaging Swift code into modules
• Using Swift classes in Objective-C
• Calling Objective-C code from Swift
• Calling C code from Swift

WROX.COM CODE DOWNLOADS FOR THIS CHAPTER

You can find the wrox.com downloads for this chapter at http://www.wrox.com/go/proswift on the Download Code tab. The code for this chapter is contained in the following files:

• CircleTool.zip
• SwiftC.zip
• SwiftMixture.zip

Swift incorporates a lot of modern language features, bringing both the iOS and OS X platforms into the twenty-first century and alleviating some of the headaches programmers had when working with Objective-C. However, because both operating systems have a strong heritage rooted in C and Objective-C, it is likely that you will have to work with code written in these languages at some point. This chapter shows some of the key features that allow Swift to interoperate with C and Objective-C, including namespaces, modules, and the functionality that bridges Swift to these older languages.

THE SUCCESSOR TO OBJECTIVE-C

Apple's release of Swift in June 2014 came as a surprise to many iOS and OS X programmers. For years, there had been speculation that Apple would release a successor to Objective-C. In 2008, development on MacRuby, an implementation of Ruby that offered near-seamless bridging between Ruby and Objective-C, ramped up. Many programmers believed that Apple would eventually bless Ruby as the ...