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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

7,181 Points

error: extra argument 'lastName' in call


I couldn't find out why i am getting this error: extra argument 'lastName' in call. Why there is no problem about the firstName but only the lastName ? I searched for a difference between them to track the error but couldn't find out.

Please help

class Person {
    let firstName: String
    let lastName: String

  init(firstName: String, lastName: String) {
       self.firstName = firstName
       self.lastName = lastName

    func getFullName() -> String {
        return "\(firstName) \(lastName)"

// Enter your code below
class Doctor: Person {
// is override init needed in this case ?? or just override the func getFullName() would be enough?
//override init (firstName: String, lastName: String) {
//super.init (firstName: firstName, lastName: lastName)
override func getFullName() -> String {
return "Dr. \(firstName) \(lastName)"

let someDoctor = Doctor.getFullName (firstName: "Bad", lastName: "Robot")

1 Answer

Ahmet, suggest you first create a Doctor object and then call the getFullName() method on that object:

let pete = Doctor(firstName: "Tom", lastName: "Jones")
let firstName = Doctor.getFullName(pete)