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iOS Object-Oriented Swift Class Inheritance Creating a Subclass

error: use of unresolved identifier 'wheels'

I'm a bit stuck in this challenge, I kept getting a bummer telling me to check the compiler errors and found this - error: use of unresolved identifier 'wheels'. I didn't quite understand what it meant, any suggestions? Thanks a lot!

objects.swift
class Vehicle {
  var numberOfDoors: Int
  var numberOfWheels: Int

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

// Enter your code below
class Car: Vehicle {
    var numberOfSeats: Int = 4

  override init(withDoors: Int, andWheels: Int, andSeats: Int) {
  super.init(withDoors: doors, andWheels: wheels, andSeats: seats)
  self.numberOfSeats = 4
  }
}

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

1 Answer

Paul Brazell
Paul Brazell
14,370 Points

I am not wanting to give answers so I'll give to suggestions:

If you get stuck editing code in the swift editor and are running into errors, try just pasting the code into a playground. This will give you better errors and be able to use the compiler as you are writing the code.

It looks like from the Car initializer that you are referencing names from the Car init that are not the names of the variables in the initializer. I'd start there.

Thanks, but I've already completed the challenge. Sorry i forgot to remove this question!