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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Properties

Brian Patterson
Brian Patterson
19,588 Points

This compiles correctly in swift

This compiles correctly in Swift but the challenge says it is wrong, why ?

class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int

    init(withDoors doors: Int, andWheels wheels: Int) {
        self.numberOfDoors = doors
        self.numberOfWheels = wheels

class car: Vehicle {
    let numberOfSeats: Int = 4
    override init(withDoors doors: Int, andWheels wheels: Int) {
        super.init(withDoors: doors, andWheels: wheels)


let someCar = car.init(withDoors: 4, andWheels: 4)

2 Answers

Bill Siever
Bill Siever
7,649 Points
  1. The class should be named "Car" with a capital C.
  2. You don't need the "init" when constructing an object. Just use the name of the class. That is, let someCar = Car(...)
12,963 Points

Bill's spot on with his answer. There's no need to update the init of the subclass either as you're setting a default value for the new variable of seats.

All you need to add is something like:

class Car: Vehicle {
    var numberOfSeats: Int = 4

let someCar = Car(withDoors: 2, andWheels: 4)