Swift

11.3    Extending Classes

Thanks to your experience with extending enumerations and structs, class extensions should be a breeze. In this section, we’ll extend the User class, as shown in Listing 11.7.

class User {    let firstName: String    let lastName: String    init(firstName: String, lastName: String) {        self.firstName = firstName        self.lastName = lastName    }}  

Listing 11.7     User Class in Its Original Form

To demonstrate further extension options, let’s extend User with an initializer and protocol conformance. The final code is shown in Listing 11.8.

class User {    let firstName: String    let lastName: String    init(firstName: String, lastName: String) {        self.firstName = firstName        self.lastName = lastName    }}extension User: CustomStringConvertible {