Experimenting with Swift protocols

CastingMadness.swift

var y = NSOrderedSet(orderedSet: my)

struct CastingGenerator<G: GeneratorType, T>: GeneratorType {
    
    typealias Element = T
    
    var base: G
    
    init(_ base: G) {
        self.base = base
    }

    mutating func next() -> Element? {
        return base.next() as! Element?
    }

}

struct CastingSequence<S: SequenceType, T>: SequenceType {
    
    typealias Generator = CastingGenerator<S.Generator, T>
    
    var base: S
    
    init(_ base: S) {
        self.base = base
    }
    
    func generate() -> Generator {
        return CastingGenerator<S.Generator, T>(base.generate())
    }
    
}


var yy = CastingSequence<NSOrderedSet, String>(my)

for test in yy {
    print(test)
}