anchor.diff:   *      });
    *
    * However, [sendPeriodically] is not supported by [LoopBackTransport], it is
  - * not error to call it on the server, however it gets send only when normal
  - * [send] is triggered.
  + * not error to call it on the server, however it gets send only first time and
  + * later times when normal [send] is triggered.
    *
    */
   library clean_ajax.client;
  
positive.code:   }
  
    /**
     * Schedule the send of ClientRequest created by factory function
     * [createRequest].
     *
     * Request will be created immediately before the send, that makes it possible
  
negative.code:   }
  
    /**
     * Schedule the [ClientRequest]s to be sent periodically and return the
     * [Stream] of responses.
     *
     * Every time the transport layer notifies [Connection] about being ready to
     * send next request, [createRequest] is executed and resulting
     * [ClientRequest] is send.
     *
     * Similarly to [send], this method will notify the transport layer there is
     * request to be sent. This notification happens only as direct consequence
     * of calling [sendPeriodically], it won't happen multiple times for single
     * [createRequest] factory.
     *
     * The returned [Stream] can have only single listener, and periodical
     * requests are canceled when the subscription to results [Stream] is
     * canceled.
     */
    Stream sendPeriodically(CreateRequest createRequest) {
      var periodicRequest = {'createRequest': createRequest};
  