Programming in Swift: Functions & Types

Jan 4 2022 · Swift 5.5, iOS 15, Xcode 13

Part 5: Protocols & Inheritance

44. Challenge: Protocols

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Previous episode: 43. Protocols & Extensions Next episode: 45. Value vs. Reference Types

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Notes: 44. Challenge: Protocols

Update Notes: This course was originally recorded in 2019. It has been reviewed and all content and materials updated as of October 2021.

Heads up... You've reached locked video content where the transcript will be shown as obfuscated text.

This is your final challenge for the course. You’ll find instructions in the playground for this part of the course. Pause the video, and give it a try. Then, come back to see my solutions. Good luck!

protocol Shape {

  var area: Double { get }
struct Square: Shape {
  let side: Double
  var area: Double {
    side * side
extension Numeric {
  var squared: Self { self * self }
struct Triangle: Shape {

  let base: Double
  let height: Double
  var area: Double  {
    0.5 * base * height
struct Circle: Shape {

  let radius: Double
  var area: Double  {
    .pi * radius.squared
let square = Square(side: 4)
let triangle = Triangle(base: 3, height: 5)
let circle = Circle(radius: 2)
let shapes: [Shape] = [square, triangle, circle]
print( { $0.area })
extension FloatingPoint {

  var isInteger: Bool {
    rounded() == self
let double: Double = 5.0
let float: Float = 3.7