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iOS Object-Oriented Swift Class Inheritance Overriding Methods

Randell Purington
Randell Purington
9,992 Points
Posted by Randell Purington
Randell Purington
9,992 Points

I could use some help.

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

I am not sure where I am getting it wrong.

when I click on preview this is what it says:

swift_lint.swift:44:19: error: use of unresolved identifier 'someDoctor' let fullName = someDoctor.getFullName() ^~~~~~~~~~

I have a feeling it is something small I am overlooking but then again I might be way off and not doing what it asks for.

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

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

   }
   let fullName = someDoctor.getFullName()

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

There are two issues with your current code, but they are indeed both pretty minor issues.

  1. You are creating the someDoctor instance within the Doctor class, rather than outside the class like you are supposed to.
  2. When you call the method you name it getFullName, but the name of the method is actually just fullName.

If you fix those two issues like this:

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

let someDoctor = Doctor(firstName: "Sam",  lastName: "Smith") // Moved outside of Doctor class
let fullName = someDoctor.fullName() // Changed getFullName to fullName

Then your code will pass.

Randell Purington
Randell Purington
9,992 Points
Randell Purington
Randell Purington
9,992 Points

THANK YOU!! I appreciate the help. it passed. Thank you!