Return from initializer without initializing all stored properties

Question

I have a simple class like this.

public class User {
    let id: Int
    let firstName: String
    let lastName: String
    let email: String?

    init(id:          


        

Answer 1

Change the email from "let" to "var" as below.

public class User {
    let id: Int
    let firstName: String
    let lastName: String
    var email: String?

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

    }
}