scatter(Fun, List) ->
       S = self(),
       Pids = [fun(I) ->
                spawn(fun() -> exec_fun(S, Fun, I) end)
               end || I <- List],
       gather(Pids).

     gather([]) -> [];
     gather([H|T]) ->
       receive
         {H, Return} -> [Return|gather(T)]
       end.

     exec_fun(Parent, Fun, Item) ->
       Parent ! {self(), catch(Fun(Item))}.