below

// In Swift 1.1, I can use "let sideshow : Sideshow!". In Swift 1.2 it has to be a var
// Is this due to the change:
// "In an initializer, constant properties can now only assign a value once." ?

class Main {
    var name : String
    let sideshow : ImplicitlyUnwrappedOptional<Sideshow>
    init (name : String, referenceName : String) {
        self.name = name
        self.sideshow = Sideshow(name: referenceName, ref: self)