anchor.diff:  
           %% Exported for code-reloading
           websocket_loop/8
  -
  -        , dialyzer_fix/0
       ]).
   
   %-compile(export_all).
  
positive.code: %% Invalid.
  is_utf8(_) ->
          false.
  
  dialyzer_fix() ->
      apply_mask(<<15:32>>, 0).
  
negative.code:             [F#frame{data=Unmasked} | parse_frame(RemainingData)]
      end.
  
  apply_mask(Mask, Data) ->
      apply_mask(Mask, Data, <<>>).
  
  apply_mask(_, <<>>, Acc) ->
      Acc;
  