+1 for recur. It was first puzzling to me, and looked like a limitation, until I saw the light. It actually forces you to make sure you not going to cause actua

+1 for recur. It was first puzzling to me, and looked like a limitation, until I saw the light. It actually forces you to make sure you not going to cause actual recursion (so no stack overflow). I also like the [] vector syntax, since you don't need to quote it (no calls expected there).