     }
     
     public class func setSharedImageCache(cache:AFImageCacheProtocol?) {
-        objc_setAssociatedObject(self, &AssociatedKeys.SharedImageCache, cache, UInt(OBJC_ASSOCIATION_RETAIN))
+        objc_setAssociatedObject(self, &AssociatedKeys.SharedImageCache, cache, .OBJC_ASSOCIATION_RETAIN)
     }
     
     public class func sharedImageCache() -> AFImageCacheProtocol {

            return (operation, request)
        }
        set {
            objc_setAssociatedObject(self, &AssociatedKeys.RequestImageOperation, newValue.operation, UInt(OBJC_ASSOCIATION_RETAIN_NONATOMIC))
            objc_setAssociatedObject(self, &AssociatedKeys.URLRequestImage, newValue.request, UInt(OBJC_ASSOCIATION_RETAIN_NONATOMIC))
        }
    }
    

}

func AFImageCacheKeyFromURLRequest(request:NSURLRequest) -> String {
    return request.URL!.absoluteString
}

class AFImageCache: NSCache, AFImageCacheProtocol {
