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iOS Object-Oriented Swift Class Inheritance Overriding Methods

India Poetzscher
PLUS
India Poetzscher
Courses Plus Student 3,821 Points

What am I doing wrong?

I've provided a base class Person in the editor below. Once an instance of Person is created, you can call fullName() and get a person's full name.

Your job is to create a class named Doctor that overrides the fullName() method. Once you have a class definition, create an instance and assign it to a constant named someDoctor.

For example, given the first name "Sam", and last name "Smith", calling fullName() on an instance of Person would return "Sam Smith", but calling the same method on an instance of Doctor would return "Dr. Smith".

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 {
 override init() {
   super.init()
   self.firstName = "Dr."

 }

}

let someDoctor = Doctor("Dr. Smith")

1 Answer

Daniel Turato
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree seal-36
Daniel Turato
Java Web Development Techdegree Graduate 30,124 Points

This should work:

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)"
  }
}

class Doctor: Person {

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

let someDoctor = Doctor(firstName: "First", lastName: "Last")

What you did wrong was that you were overriding the init method which doesn't need to be done, but instead you needed to override the fullName method. Hope this helps.