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

Alexandru Gugoasa
Alexandru Gugoasa
2,941 Points

This task can not be completed using code that works in an XCode Playground.

This is the code:

class Robot: Machine { override func move(direction: String) { switch direction { case "Up": self.location = (Point(x: 0, y: 1)) case "Down": self.location = (Point(x: 0, y: -1)) case "Left": self.location = (Point(x: -1, y: 0)) case "Right": self.location = (Point(x: 1, y: 0)) default: break } } }

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! Im a machine!")
  }
}

// Enter your code below

class Robot: Machine {
    override func move(_ direction: String) {
        switch _ direction {
        case "Up":
            self.location = (Point(x: 0, y: 1))
        case "Down":
            self.location = (Point(x: 0, y: -1))
        case "Left":
            self.location = (Point(x: -1, y: 0))
        case "Right":
            self.location = (Point(x: 1, y: 0))
        default: break
        }
    }
}

2 Answers

Ryan Lee
Ryan Lee
13,806 Points

just need to remove the underscore after switch, direction is the local argument name used to pass the input argument along to the switch statement

Alexandru Gugoasa
Alexandru Gugoasa
2,941 Points

Thank you very much Ryan, that underscore gave me a lot of trouble.

Ryan Lee
Ryan Lee
13,806 Points

yeah it's always the little things ain't it? ;)