DB<1> @a = 1..9; DB<2> map{ $_ = ++$_% 10 } @a; DB<3> x @a 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 0 DB<4> #### map { $_ ++; $_ = $_ % 10} @a;