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

Chase Grainger
Chase Grainger
4,830 Points
Posted by Chase Grainger
Chase Grainger
4,830 Points

I think this challenge has some bugs in it.

Can someone tell me what is wrong with my code? It seems as though some of the code is being recognized as comments.

robots.swift 
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'm a machine!")
  }
}

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

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The workspace is a bit bugged true, but the bug only affects the code highlighting. It does not affect the functionality of your code. The issue with your solution is that you are missing the _ that the move function has as its external parameter name.

When overriding functions the function declaration has to match exactly with the one being overridden, any difference at all will make the override invalid.

So simply adding that _ like this:

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

Will make your code pass the challenge.