Congratulations! You’ve completed a pretty long and complex lesson. You learned how to:

  • Define and conform to custom protocols
  • Conform to protocols in the Swift standard library
  • Use protocol inheritance
  • Provide default protocol implementation using protocol extensions
  • Define generic functions
  • Define generic types
  • Define generic protocols with associated types
  • Write functions that return opaque types

You’ll be using protocols and generics extensively as an iOS developer, so make sure to review these concepts!


Feel free to utilize the empty Review.swift file and output terminal on the right to hone your understanding of protocols and generics.

Click on “Up Next” when you’re ready to move on.

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