anchor.diff:      {ok, Client} -> {reply, {ok, Client}, State};
       error -> {reply, {error, invalid}, State}
     end;
  +
  +handle_call({create_table}, From, State) ->
  +  NextId = State#state.table_cnt + 1,
  +  {ok, NewTable} = table:start(From),
  +  Tables1 = [NewTable|State#state.tables],
  +  {reply, {ok, NewTable, NextId}, State#state{tables=Tables1, table_cnt=NextId}};
   
   handle_call(Request, _From, State) ->
     io:format("~w received unknown call ~p~n",
  
positive.code: get_client_by_cookie(Cookie) ->
    gen_server:call({global, ?MODULE}, {get_client_by_cookie, Cookie}).
  
  % gen_server:
  init([]) ->
    {ok, #state{id=orddict:new(),
                cookie=orddict:new()}}.
  
  % TODO: Set monitor on client, clear cookie when dies.
  handle_call({get_client, Id}, _From, State) ->
  
negative.code: 
  % id is Id -> {Client, Cookie}
  % cookie is Cookie -> Id
  % tables is orddict of table_id -> table
  % table_cnt counter for next id
  -record(state, {id, cookie, tables, table_cnt}).
  
  % Public:
  start() ->
  