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iOS Enumerations and Optionals in Swift Introduction to Enumerations Enums and Objects

Garrick Henne
Garrick Henne
3,868 Points

What does the the move(_ direction: Direction) method output? Why does it still work without one?

I am trying to figure out what the function is supposed to output, i thought it would be -> Point or location but those dont seem to work. But when i complete the function with the output being empty it still works somehow anyway, why is this?

class Point {
    var x: Int
    var y: Int

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

enum Direction {
    case left
    case right
    case up
    case down

class Robot {
    var location: Point

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

    func move(_ direction: Direction) {
        // Enter your code below

1 Answer

Clark Reilly
Clark Reilly
6,204 Points

It shouldn't output anything. It should only change the values of Robot

func move(_ direction: Direction) /* -> nil/void/zip/nada */ {
  switch direction
  case right: location.x += 1
  //You can do the rest from here.