SchrodingerCat.kt

class Cat {
    val meow = "Meowww...? :3"
}

fun main(args: Array<String>) {
    var aBoringClassInstance: Cat? = Cat()
    aBoringClassInstance!!

    val sureNull: Cat? = null
    sureNull!!
    // oops! NPE :/
  
    val maybeACat = openBox()
    val meow = maybeACat?.meow!!
    // NPE...?
}

fun openBox(): Cat? {
    return if (Random().nextInt(2) == 0) Cat()
    else null
}