anchor.diff:  handle_call(get_readystate, _From, State = #state{readystate = S}) ->
       {reply, S, State};
   handle_call(get_frame, _From, State = #state{readystate = ?OPEN}) ->
  -    {Frame, NewState} = receive_frame(State),
  -    {reply, Frame, NewState};
  +    {Result, NewState} = receive_frame(State),
  +    {reply, Result, NewState};
   handle_call(get_frame, _From, State) ->
       {reply, {error,connection_not_open}, State};
   handle_call(_Request, _From, State) ->
       {reply, ok, State}.
   handle_cast(
     {send, Op, Data},
  -  State = #state{sock = Sock, readystate = ?OPEN}
  - ) ->
  +  State = #state{sock = Sock, readystate = ?OPEN}) ->
       ok = gen_tcp:send(Sock, frame(Op,Data)),
       {noreply, State}.
   
  
positive.code: decode_len(<<126:7, Len:16, Rest/bytes>>) ->
      {Len, Rest};
  decode_len(<<Len:7, Rest/bytes>>) ->
      {Len, Rest}.
  
  %% Local variables:
  %% mode: erlang
  
negative.code: 
  encode_len(Len) when Len < 126 ->
      << Len:7 >>;
  encode_len(Len) when Len =< 16#ffff ->
      << 126:7, Len:16 >>;
  encode_len(Len) when Len =< 16#7fffffffffffffff ->
      << 127:7, Len:64 >>.
  
  decode_len(<<127:7, Len:64, Rest/bytes>>) ->
  