09:28:40 <_jacco> ixset question: how would I efficiently query for the first/second/... "n element", given a certain ixset which is a subset after some filtering (perhaps by using a key? every item contains a unique integer id, but note that I do not just want to query a range, since the items are just a subset). I found "groupAscBy", but it is not clear to me whether this resulting list is lazy enough.