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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

Marina Alenskaja
Marina Alenskaja
9,320 Points
Posted by Marina Alenskaja
Marina Alenskaja
9,320 Points

Why didn't I need to use an initializer for the code to work?

Hi

I'm a bit confused - I solved the challenge, but I don't understand why I didn't have to write an init method for the subclass Doctor, for the code to work?

Here is what I wrote:

class Doctor: Person {

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

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

1 Answer

rh12
rh12
4,407 Points

Hi Marina,

The reason has to do with inheritance. The super class "Person" has an init method that takes first and last name parameters. Since "Doctor" is a subclass, or is inheriting its characteristics from the "Person" class, you do not need to specify that particular init method again.

A sub-class inherits the following from their super class: Properties, Methods (including Initializers) and Subscripts.

Hope this helps.

Ryan

More information about inheritance (in Swift) can be found here: The Swift Programming Language - Inheritance