Generic function to make an array of types from incoming JSON

NSJSONSerialization+marshalling.swift

protocol FromJSONAble {
    init(JSONDictionary: NSDictionary)
}

extension NSJSONSerialization {
    
    class func unmarshallArray<T: FromJSONAble>(data: NSData)-> T[] {
        var jsonError: NSError?
        let roughResults = self.JSONObjectWithData(data, options: NSJSONReadingOptions(0), error: &jsonError) as NSArray
        
        var results = T[]()
        for object : AnyObject in roughResults {
            results.append(T(JSONDictionary: object as NSDictionary))
        }
        
        return results
    }
    
}