Right, but I wasn't familiar with it. This time, I thank you for pointing it out for me. ^_^
I meant to convey that I'd rather write Arc code so that sentinel values are generated using [] or whatnot, rather than introducing uninterned symbols to the language. Uninterned symbols make it much less of a pain for multiple threads to generate unique variable names, but they introduce complexity in other places. Besides the hypothetical examples I already mentioned, I'm happy I can enter (uniq) symbols at the REPL when I'm debugging.
I don't really expect this opinion to catch on, but I'm throwing it out there just in case.
