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iOS Build a Simple iPhone App with Swift Getting Started with iOS Development Swift Recap Part 2

Rea Rahhal
Rea Rahhal
Courses Plus Student 4,732 Points

I am really trying to figure out what's happening

The method is overrides correctly however I am unable to run the code

class Point {
  var x: Int
  var y: Int

  init(x: Int, y: Int) {
    self.x = x
    self.y = y

class Machine {
  var location: Point

  init() {
    self.location = Point(x: 0, y: 0)

  func move(direction: String) {
    print("Do nothing! I am a machine!")

// Enter your code below
class Robot: Machine {
    override func move(direction: String) {
        switch direction {
            case "Up": self.location.y += 1
            case "Down": self.location.y -= 1
            case "Right": self.location.x += 1
            case "Left": self.location.x -= 1
        default: print("Do nothing") // Or you could put a break clause per the instructions

1 Answer

Hi there,

If you add the underscores back into both method signatures, your code is fine.