anchor.diff:  		MatchId :: Match,
   		MatchProduct :: Match,
   		Match :: {exact, string()} | {notexact, string()} | {like, string()},
  -		Result :: {Cont1, [#service{}]} | eof | {error, Reason},
  -		Cont1 :: any(),
  +		Result :: {Cont1, [#service{}]} | {error, Reason},
  +		Cont1 :: eof | any(),
   		Reason :: term().
   %% @doc Query services 
   query_service(Cont, MatchId, '_') ->
  
positive.code: 		MatchId :: Match,
  		MatchLocale ::Match,
  		Match :: {exact, string()} | {notexact, string()} | {like, string()},
  		Result :: {Cont1, [#httpd_user{}]} | eof | {error, Reason},
  		Cont1 :: any(),
  		Reason :: term().
  %% @doc Query the user table.
  query_users(start, '_', MatchLocale) ->
  
negative.code: 		MatchOffer ::  Match,
  		MatchService ::  Match,
  		Match :: {exact, string()} | {notexact, string()} | {like, string()} | '_',
  		Result :: {Cont1, [#product{}]} | {error, Reason},
  		Cont1 :: eof | any(),
  		Reason :: term().
  %% @doc Query product
  query_product(Cont, '_' = _MatchId, MatchOffer, MatchService) ->
  