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Having trouble with a task

In the editor you've been provided with two classes: Point to represent a coordinate point, and Machine. The machine has a move method that doesn't do anything.

Your task is to subclass Machine and create a new class named Robot. In the Robot class, override the move method and provide the following implementation:

If you enter the string "Up" the y coordinate of the Robot's location increases by 1. "Down" decreases it by 1. If you enter "Left", the x coordinate of the location property decreases by 1 while "Right" increases it by 1.

Note: If you use a switch statement you can use the break statement in the default clause to exit the current iteration.

class Robot: Machine {
  override func move(direction: String){
        switch direction{
            case up: Up(x:0, y:1)
            case down: Down(x:0, y:-1)
            case left: Left(x:-1, y:1)
            case right: Right(x:1, y:0)
            default: break

The other posts on this task are outdated and I can't figure this out.

1 Answer

I figured it out after an hour... For those of you who view this in the future.

class Robot: Machine {
    override func move(_ direction: String) {
        switch direction {
        case "Up": self.location.y += 1
        case "Down": self.location.y -= 1
        case "Left": self.location.x -= 1
        case "Right": self.location.x += 1
        default: break

It's important to make sure an underscore( _ ) comes before (direction: String) { as showcased above.