@inthehands @quephird @jrose indeed, but I would make similar reservations about recursive structures, as they imply pointers, memory layouts yada, yada. If you had told me in 2000 that the heap / stack would be some proeminent in newer languages like Swift I would have looked at you funny (Swift even has a keyword for recursive members). Mind you, this is no criticism, more me looking at the courses I gave and thinking “Mmh”.