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

vivek d
seal-mask
.a{fill-rule:evenodd;}techdegree
vivek d
iOS Development Techdegree Student 1,596 Points

why is this not right?

why is it not compiling?

robots.swift
class Point {
  var x: Int
  var y: Int

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

class Machine: Point {
  var location: Point

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

  func move(_ direction: String) {
    print("Do nothing! I am 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 

  }

}

}

let rob1 = Robot()
rob1.move(_ : "Up")

1 Answer

Matthew Long
Matthew Long
28,383 Points

Your Robot class is correct except one of the cases in your switch statement is looking at left instead of Left. Just change that and you're good.

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 
    }
  }
}