lowerBound / upperBound API?

[nornagon]

Would be great to be able to fetch the largest key smaller than a given search value (and vice-versa)

[w8r]

you can do it with .range(lo, hi, fn) ?

[nornagon]

ah hm, i think that can only go one direction though? since it starts from lo and goes to hi. if i have a tree sorted in ascending order, there's no way to get the largest key smaller than k in O(log n), right? unless i'm misunderstanding the range functionality.