> Today I was wonder is it possible to create a function for binary search
> inside flatten or nested lists.
> If I have ordered list I need something faster that O(n) and I should not
> care of unique structure.
> It was a goal while walking in the forest.
You can do a binary search also in a linked list.
See e.g. the 'balance' function in @lib/misc.l (not a binary *search*,
but an analog processing).