anchor.diff:      Error ->
           throw(Error)
       end.
  +
  +trigger_group_update(Pid, RequestSeq) ->
  +    gen_server:cast(Pid, {update_group, RequestSeq}).
   
   % from template
   start_link(InitArgs) ->
  
positive.code: handle_call(request_group_info, _From, State) ->
      GroupInfo = get_group_info(State),
      {reply, {ok, GroupInfo}, State}.
  
  handle_cast({start_compact, CompactFun}, #group_state{compactor_pid=nil}
          = State) ->
  
negative.code: -behaviour(gen_server).
  
  %% API
  -export([start_link/1, request_group/2, trigger_group_update/2, request_group_info/1]).
  -export([open_db_group/2, open_temp_group/5, design_doc_to_view_group/1,design_root/2]).
  
  %% gen_server callbacks
  