What is wrong with my subclass?

Question

The return line doesn't work and it claims that my self.title is not being initialized in the superclass. How do I fix this.

objects.swift

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 {
  var title: String
  override init(firstName: String, lastName: String) {
    super.init(firstName: firstName, lastName: lastName)
    title = "Dr. "
  }
  override func fullName() -> String {
    return "\(title) \(lastName)"
  }
}

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

Answer 1 · 2017-06-24T05:30:58Z

June 24, 2017 5:30am

Seeing as how the title property will always need to be equal to 'doctor' in case of this Doctor class, it is better practice to denote it's value in the class body rather than the initializer. This also avoids needlessly assigning the title as a variable in memory. Your class body should look like this:

class Doctor: Person {
    let title = "Dr. "

Also, we need to assign the constant 'someDoctor' to an instance of Doctor. For this, we don't need to call the init method directly. Lastly, you need to delete the call to the fullName method at the end of the Doctor initialization, as it returns a string, and we want the full instance of the Doctor object. After these changes, your code should look like this:

class Doctor: Person {
  let title = "Dr. "
  override init(firstName: String, lastName: String) {
    super.init(firstName: firstName, lastName: lastName)
  }
  override func fullName() -> String {
    return "\(title) \(lastName)"
  }
}

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

Hope this helps. -Charles

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Varun Kukunoor

Varun Kukunoor

What is wrong with my subclass?

1 Answer

Charles Kenney

Charles Kenney