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

Posted by Disha Mohta
Disha Mohta
2,248 Points

still doesn't work after changing the -+ to -=

Biggest compiling error, is on the move function

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!")
  }
}

// Enter your code below
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
    }
  }
}
mathisvester
mathisvester
13,451 Points
mathisvester
mathisvester
13,451 Points

You forgot the underscore for your external parameter name in your "move function".

Example: 

func move(_ direction: String) {
    print("Do nothing! I'm a machine!")
}

If you don’t want an argument label for a parameter, write an underscore (_) instead of an explicit argument label for that parameter.

Please read the section Omitting Argument Labels of the Swift Documentation / Functions for more information.