FREE: Read a new Swift article every day – click here! >>

< Previous: Protocol-oriented programming   Next: Handling missing data >

Protocols and extensions summary

You’ve made it to the end of the ninth part of this series, so let’s summarize:

  1. Protocols describe what methods and properties a conforming type must have, but don’t provide the implementations of those methods.
  2. You can build protocols on top of other protocols, similar to classes.
  3. Extensions let you add methods and computed properties to specific types such as Int.
  4. Protocol extensions let you add methods and computed properties to protocols.
  5. Protocol-oriented programming is the practice of designing your app architecture as a series of protocols, then using protocol extensions to provide default method implementations.

Need to know Objective-C fast?

I wrote a book dedicated to teaching Objective-C to developers who already know Swift – it's the fastest way to get up to speed!

< Previous: Protocol-oriented programming   Next: Handling missing data >
MASTER SWIFT NOW
Buy Testing Swift Buy Practical iOS 12 Buy Pro Swift Buy Swift Design Patterns Buy Swift Coding Challenges Buy Server-Side Swift (Vapor Edition) Buy Server-Side Swift (Kitura Edition) Buy Hacking with macOS Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with Swift Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let me know!

Click here to visit the Hacking with Swift store >>