> nums := seq( 1 .. 10 );
                          nums := 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

> foldl( `+`, 0, nums ); # compute sum using foldl
                          55

> foldr( `*`, 1, nums ); # compute product using foldr
                          3628800