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

Em Har
Em Har
9,775 Points

In the editor below you have two objects - classes named Point and Robot. The Robot stores its location as a point insta

Can someone walk me through my issue on 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
      switch direction{
      case Direction.up: return location.y +=1
      case Direction.down: return location.y -=1
      case Direction.right: return location.x +=1
      case Direction.left: return location.x -=1

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points


So the basic thing to do here is a "switch" within the "move" method. And you want to switch on the method's parameter "direction".

 // This goes inside the "move" method.

      switch direction {
        case .up: 
        location.y += 1
        case .down:
        location.y -= 1
        case .right:
        location.x += 1
        case .left
        location.x -= 1
        default: break

Here what we are doing is checking every possible "direction", and adding a point to location.

If you need more help please reply to this threat.

Good luck