anchor.diff:  %% @end
   %%--------------------------------------------------------------------
   -spec pmap_gather(PIDs :: [pid()], Ref :: reference(), Acc :: list()) ->
  -    list() | error.
  +    list().
   pmap_gather([], _Ref, Acc) -> lists:reverse(Acc);
   pmap_gather([PID | T] = Pids, Ref, Acc) ->
       receive
  
positive.code:                 true ->
                      pmap_gather(Pids, Ref, Acc);
                  false ->
                      error
              end
      end.
  
  
negative.code: %% A  parallel version of lists:map/2. See {@link lists:map/2}
  %% @end
  %%--------------------------------------------------------------------
  -spec pmap(Fun :: fun((X :: A) -> B), L :: [A]) -> [B].
  pmap(Fun, [X]) ->
      [catch Fun(X)];
  pmap(Fun, L) ->
  