     
     internal enum ContentLengthResult {
         case success(Int64?, [IsCached])
-        case canceled
+        case cancel
         case failure(Error)
     }
 

    }
    
    private func contentLength(of item: Item, _ callback: @escaping (ContentLengthResult) -> ()) {
        guard !canceled else {
            callback(.canceled)
            return
        }
        

                
                self.contentLength(of: tail) { result in
                    switch result {
                    case .cancel, .failure:
                        callback(result)
                    case let .success(tailLength, tailCached):
                        guard let tailLength = tailLength else {
