anchor.diff:                        error_logger:error_msg("~p~n~p~n", [Reason, erlang:get_stacktrace()])
                 end
         end, Matches),
  -    match_and_run(Text, Rest).
  +    ?IIF(Matches =:= [], match_and_run(Text, Rest), match).
   
   -spec matches(binary(), binary()) -> [[binary()]].
   matches(Text, Pattern) ->
  
positive.code: do_1(#{<<"attachments">> := [#{<<"pretext">> := PreText}]} = In) ->
      do_1(In#{<<"text">> => PreText, <<"attachments">> => nil});
  do_1(#{<<"type">> := <<"message">>, <<"text">> := Text, <<"channel">> := Channel}) ->
      match_and_run(Text,
                    [
                     {<<"https?://[^\s]*(pull|issue)/[0-9]*">>,         {?MODULE, task_github_url, ['$$']}},
                     {{mention, <<"list(.*)">>},                        {?MODULE, task_list,       ['$1', Channel]}},
                     {{mention, <<"register\s+([^\s]*)\s+([^\s]*)">>},  {?MODULE, task_register,   ['$1', '$2', Channel]}},
                     {{mention, <<"user\s+([^\s]*)">>},                 {?MODULE, task_user,       ['$1', Channel]}},
                     {{mention, <<"help">>},                            {?MODULE, task_help,       [Channel]}}
                    ]);
  do_1(#{<<"type">> := <<"presence_change">>, <<"presence">> := <<"active">>, <<"user">> := SlackId}) ->
      _ = preminder_user:slack_id_to_mail(SlackId),
      ok;
  
negative.code:     ok.
  
  match_and_run(_, []) ->
      nomatch;
  match_and_run(Text, [{{mention, Pattern}, {M, F, Args}} | Rest]) ->
      SlackId = preminder_slack:slack_id(),
      case matches(Text, <<"<@", SlackId/binary, "(\|[^>]*)?>">>) of
          [] ->
              match_and_run(Text, Rest);
          [[Mention|_] | _] ->
              case match_and_run(binary:replace(Text, Mention, <<>>, [global]), [{Pattern, {M, F, Args}}]) of
                  match   -> match;
                  nomatch -> match_and_run(Text, Rest)
              end
      end;
  match_and_run(Text, [{Pattern, {M, F, Args0}} | Rest]) ->
      Matches = matches(Text, Pattern),
  