Empty
Uniqueness is such an interesting post constraint; and I so enjoy systems with considered constraints--after all, why should a baseball double as an egg (or vice versa)? And if you really want to repeat something, nonce up? I might test that hunch. Looking forward to spending some time here.
Burensasub
Yeah, I was annoyed by this at first but perhaps it may end up being another constraint /limitation that we can creatively work around