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Start your free trialAananya Vyas
20,157 Pointsit says - super.init isn't called on all paths before returning from initializer
?
class Vehicle {
var numberOfDoors: Int
var numberOfWheels: Int
init(withDoors doors: Int, andWheels wheels: Int) {
self.numberOfDoors = doors
self.numberOfWheels = wheels
}
}
class Car: Vehicle {
var numberOfSeats : Int = 4
init (numberOfSeats : Int){
self.numberOfSeats = numberOfSeats
}
}
let someCar = Car (numberOfSeats : 5 )
1 Answer
David Papandrew
8,386 PointsSince the task only asks you to create a new subclass, Car, with a single default store property, you only need minimal code for the subclass. You don't need an initializer, since the new property is set to default value (4) and all other aspects of Car are same as Vehicle.
Here is the code:
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
}
let someCar = Car(withDoors: 4, andWheels: 4)
If you did want to include a subclass initializer, you could. This code will also pass the challenge. In this case, you set the subclass specific properties FIRST in the initializer, then you call super.init and pass all the inherited properties to that method (see code below).
class Vehicle {
var numberOfDoors: Int
var numberOfWheels: Int
init(withDoors doors: Int, andWheels wheels: Int) {
self.numberOfDoors = doors
self.numberOfWheels = wheels
}
}
class Car: Vehicle {
var numberOfSeats : Int = 4
init(numberOfSeats : Int, withDoors doors: Int, andWheels wheels: Int){
self.numberOfSeats = numberOfSeats
super.init(withDoors: doors, andWheels: wheels)
}
}
let someCar = Car(numberOfSeats: 4, withDoors: 4, andWheels: 4)