anchor.diff:           _, ModulesLoad, ModulesUnload, _, _,
            DestRefresh, TimeoutInit, TimeoutAsync, TimeoutSync,
            DestDenyList, DestAllowList, Options]
  -        when Module =/= undefined, ModuleState =:= undefined,
  -             ModulesLoad == [], ModulesUnload == [],
  -             DestRefresh =:= undefined, TimeoutInit =:= undefined,
  -             TimeoutAsync =:= undefined, TimeoutSync =:= undefined,
  -             DestDenyList =:= invalid, DestAllowList =:= invalid,
  -             Options == [] ->
  +        when (Module =/= undefined) andalso (ModuleState =:= undefined) andalso
  +             (ModulesLoad == []) andalso (ModulesUnload == []) andalso
  +             (DestRefresh =:= undefined) andalso
  +             (TimeoutInit =:= undefined) andalso
  +             (TimeoutAsync =:= undefined) andalso
  +             (TimeoutSync =:= undefined) andalso
  +             (DestDenyList =:= invalid) andalso
  +             (DestAllowList =:= invalid) andalso
  +             (Options == []) ->
  +            {error, {service_update_invalid,
  +                     no_update}};
  +        [Type, _, _,
  +         FilePath, Args, Env,
  +         _, ModulesLoad, ModulesUnload, _, _,
  +         DestRefresh, TimeoutInit, TimeoutAsync, TimeoutSync,
  +         DestDenyList, DestAllowList, Options]
  +        when (Type =:= external) andalso
  +             (FilePath =:= undefined) andalso
  +             (Args =:= undefined) andalso
  +             (Env =:= undefined) andalso
  +             (ModulesLoad == []) andalso (ModulesUnload == []) andalso
  +             (DestRefresh =:= undefined) andalso
  +             (TimeoutInit =:= undefined) andalso
  +             (TimeoutAsync =:= undefined) andalso
  +             (TimeoutSync =:= undefined) andalso
  +             (DestDenyList =:= invalid) andalso
  +             (DestAllowList =:= invalid) andalso
  +             (Options == []) ->
               {error, {service_update_invalid,
                        no_update}};
           [_, Module, ModuleState,
  
positive.code:          _, _, _,
           _, _, _, _, _,
           DestRefresh, _, _, _, _, DestListAllow, _]
          when not (is_list(DestListAllow) orelse
                    (DestListAllow =:= undefined) orelse
                    (DestListAllow =:= invalid)) orelse
               ((DestRefresh =:= none) andalso is_list(DestListAllow)) ->
              {error, {service_update_dest_list_allow_invalid,
                       DestListAllow}};
  
negative.code:          _, _, _,
           _, _, _, _, _,
           DestRefresh, _, _, _, DestListDeny, _, _]
          when not ((DestListDeny =:= invalid) orelse
                    is_list(DestListDeny) orelse
                    (DestListDeny =:= undefined)) orelse
               ((DestRefresh =:= none) andalso is_list(DestListDeny)) ->
              {error, {service_update_dest_list_deny_invalid,
                       DestListDeny}};
  