.swift

// This “solves“ http://inessential.com/2015/08/02/swift_diary_7_protocols_arrays_and_c
//
// But it turns into a small nightmare of generics, where every concrete class which
// conforms to NodeRepresentedObject has to be generic, because of those strange “Self
// or associated type requirements”. And that generics turn up a lot of more than one
// wants.
//
// The good part: One has to be explicit about ones requirements for the concrete children
// of a concrete node in Brents seemingly “outline-based” fictional mail client. Is that a good
// thing? Can an Email Message contain other nodes? Is that wanted?
// The bad part: One has to be explicit.



protocol NodeRepresentedObject : class {
    typealias Children = NodeRepresentedObject
    
    var children: [Children]? {get}
}

protocol EmailMessage : NodeRepresentedObject {
    // stuff here…
}

class Mailbox<T : EmailMessage> : NodeRepresentedObject {
    
    var messages = [T]()
    var children: [T]? {
        get {
            return messages
        }
    }
}