anchor.diff:  encode_len(Len) when Len =< 65535 ->
       << 126:7, Len:16 >>;
   encode_len(Len) when Len =< 18446744073709551615 ->
  -    << 127:7, Len:64 >>.    
  +    << 127:7, Len:64 >>.
   
   decode_len(<<127:7, Len:64, Rest/bytes>>) ->
       {Len, Rest};
  
positive.code:     mask(Data, <<Mask:32>>).
  
  op_to_atom(?OP_TEXT) -> text;
  op_to_atom(?OP_BINARY) -> binary; 
  op_to_atom(?OP_PING) -> ping; 
  op_to_atom(?OP_PONG) -> pong; 
  op_to_atom(?OP_CLOSE) -> close. 
  
  unframe(<< F:1, _:3, Op:4, M:1, Data/bits >>) ->
      {Len, Rest} = decode_len(Data),
  
negative.code: handle_control(_,_) ->
      ok.
  
  op_cont(Cop, ?OP_CONT) ->
      Cop;
  op_cont(_, Op) ->
      Op.
  
  key() ->
  