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iOS Object-Oriented Swift Class Inheritance Overriding Methods

"Double check the implementation of the overridden method to match the directions specified" whats wrong

cant undertand why my code isint working

class Person {
  let firstName: String
  let lastName: String 

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

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

// Enter your code below
class Doctor: Person {

    override init(firstName: String, lastName: String) {
        super.init(firstName : firstName, lastName : lastName)

    override func fullName() -> String {
        return "Dr \(lastName)"

let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")

2 Answers

Jason Anders
Jason Anders
Treehouse Moderator 145,858 Points

Hi there,

Where you get an error like "Double check the implementation of the overridden method to match the directions specified" it means your code is likely correct in syntax, but it is not following the instructions laid out.
Challenges are very strict and specific in the instructions, and they must be followed explicitly in order for the task to pass.

Here, there are two issues:

First, the instructions say to override "the fullname() method", but you are also overriding the init() method, which was not asked for, and is not needed as the Doctor class inherits from the Person class and the Person class already has the proper init(). So, you need to delete the overriding of the init().

Second, the instructions say to output (for example) "Dr. Smith". ** Notice the period after "Dr"? This is missing in your string. And, yes, this missing puncuation will result in a Bummer.

Once those errors are fixed up, the challenge will pass.

But really nice work on the methods!! Just remember, if the instructions don't ask for it... don't do it. :smiley:

Keep coding! :) :dizzy:

Thanks Jason. Who would have thought it was all because of a period"."

Great tip "if the instructions don't ask for it... don't do it. " - this is gold