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iOS Swift 2.0 Enumerations and Optionals Introduction to Enumerations Enums and Objects

Jane Lee
Jane Lee
1,526 Points
Posted by Jane Lee
Jane Lee
1,526 Points

Enums and object challenge 1

2 Questions regarding this challenge:

  1. I'm not sure why the editor is saying ".Up" can't be identified.
  2. Why is "location.y" and not "Direction.y"

Thanks in advance!

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

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

enum Direction {
    case Left 
    case Right
    case Up
    case Down
}


class Robot {
    var location: Point

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

    func move(direction: Direction) {
        // Enter your code below
        switch {
        case .Up: location.y += 1
        case .Down: location.y -= 1
        case .Right: location.x += 1
        case .Left: location.x -= 1

        }
    }
}

2 Answers

Ryan Huber
Ryan Huber
13,021 Points
Ryan Huber
Ryan Huber
13,021 Points

In regards to your first question .Up is not identified because your switch statement does not have a condition to compare. It should be comparing to the direction you are passing in.

  // Enter your code below
        switch direction {
        case .Up: location.y += 1
        case .Down: location.y -= 1
        case .Right: location.x += 1
        case .Left: location.x -= 1

        }

In response to your second question, you are making a change to the location and as such you should manipulate that property based on the direction you tell it to move.

Let me know if you have any other questions!

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

So close! You just left out one word. The switch statement needs something to switch on:

switch direction {

Direction is a type. location is a Point object.