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iOS Build a Simple iPhone App with Swift 2.0 Getting Started with iOS Development Swift Recap Part 2

use of unresolved identifier x , y

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 {

let isRobot: Bool = true

override func move (direction: String) {

switch direction { case "Up": y++ case "Down": y-- case "Left": x-- case "Right": x++ default: break

} } }

classes.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 {

let isRobot: Bool = true

override func move (direction: String) {

switch direction {
case "Up":
y++
case "Down":
y--
case "Left":
x--
case "Right":
x++
default:
break

   }
  }
 }

2 Answers

In your switch statement, you need to call x, y on your location variable and assign a new value.

Thanks Sid for your help.

Reed Carson
Reed Carson
8,306 Points

it doesnt know what x and y are. Those are properties of your location variable so you need to access it that way

Thank you for your help Reed. It helped me to solve the problem