SwiftProperty.swift

//: Playground - noun: a place where people can play

import UIKit

var str = "Hello, playground" {
    //"Hello, playground"
    willSet {
        print("willSet \(str) : \(newValue)")
        // "willSet Hello, playground : Hello, Antonio.\n"
        str = "Hi"
        // "Hi"
        print("willSet \(str) : \(newValue)")
        //"willSet Hi : Hello, Antonio.\n"
    }
    didSet {
        print("didSet \(str) : \(oldValue)")
        //"didSet Hello, Antonio. : Hello, playground\n"
        
        str = "Hi"
        // "Hi"
        print("willSet \(str) : \(oldValue)") //
        //"didSet Hi : Hello, playground\n"
    }
}
str = "Hello, Antonio."
// "Hello, Antonio."