anchor.diff:      case InitMod:InitFun(Port) of
           ok ->
               {ok, Port};
  -        Error ->
  +        {error, Error} ->
               error_logger:error_report(Error),
               throw({error, init_failed})
       end.
  
positive.code:         {error, ErrorJson} when is_binary(ErrorJson) ->
              {struct, [{<<"error">>, {struct, Error}}]} = mochijson2:decode(ErrorJson),
              {error, Error};
          Result ->
              Result
      end.
  
  eval_js(Ctx, Js) ->
  
negative.code:                 {struct, [{<<"error">>, Error}]} ->
                      {error, Error}
              end;
          {error, Error} ->
              {error, Error}
      end.
  
  %% Internal functions
  