Set<T> that passes by reference

BoxedSet

// Set<T> is a struct in Swift, meaning it passes by value, not reference.
// I had to create this so I could pass a Set to another view controller
// and have it actually modify the Set on the original view controller as
// there was only a Back button, not an OK/Done button in the interface.

func ==<T : Hashable>(lhs: BoxedSet<T>, rhs: BoxedSet<T>) -> Bool {
    return lhs.set == rhs.set
}

final class BoxedSet<T : Hashable> : Hashable, CollectionType, ArrayLiteralConvertible {
    typealias Element = T
    typealias Index = SetIndex<T>
    typealias GeneratorType = SetGenerator<T>
    
    var set = Set<T>()
    
    init(arrayLiteral elements: Element...) {
        set = Set<T>(elements)
    }
    
    init(_ foo: BoxedSet<T>) {
        set = Set<T>(foo)
    }
    
    func generate() -> GeneratorType {
        return set.generate()
    }
    
    var hashValue: Int {
        get {
            return set.hashValue
        }
    }
    
    var startIndex: Index {
        get {
            return set.startIndex
        }
    }
    
    var endIndex: Index {
        get {
            return set.endIndex
        }
    }
    
    subscript (position: Index) -> Element {
        get {
            return set[position]
        }
    }
    
    func contains(member: Element) -> Bool {
        return set.contains(member)
    }
    
    func insert(member: Element) {
        set.insert(member)
    }
    
    func remove(member: Element) -> Element? {
        return set.remove(member)
    }
}