Lesson 12 - Type casting and object hierarchy in Swift

Swift OOP Type casting and object hierarchy in Swift

In the previous lesson, Protocols (interfaces) in Swift, we learned about protocols and created a Pterodactyl class. In today's Swift tutorial, we're going to continue working on this project. We'll also go over type casting and reveal more secrets of the object-oriented programming.

Type casting

Let's go back to our previous project (the one for protocols) and change the code in the main.swift file to have our pterodactyl stored in a variable of the BirdProtocol type:

let bird : BirdProtocol = Pterodactyl()

We're allowed to do that because the Pterodactyl class implements

...End of the preview...

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You'll learn how to cast an instance to another data type using protocols in Swift. You'll also learn to create an object hierarchy.

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