Computed Properties.swift

// Stored & computed properties example

struct Person {
    
    // strored properties
    var firstName: String
    var lastName: String
    
    // computed property
    var fullName: String {
        // getter
        get {
            return " \(firstName) \(lastName)"
        }
        // setter
        set (newFullName) {
            
            // split the names with an empty space
            let newFullNameSubstring = newFullName.split(separator: " ")
            
            // make sure there are at least 2 names
            guard newFullNameSubstring.count >= 2 else {print("New name has to contain 2 names"); return }
            
            // map new value as string
            let nameStrings = newFullNameSubstring.map(String.init)
            
            // assign the new values to stored property, so the getter will have the new values
            firstName = nameStrings.first!
            lastName = nameStrings.last!
        }
    }
}

var person = Person(firstName: "Pete", lastName: "Waveee")
person.fullName // returns the values used when instantiating the object
person.fullName = "Peter 34444" // assigns new values ( settable computed property)
person.fullName // returns the new value