Module Record_builder__Hlist.Element_index
val first_element : (('head, _) cons, 'head) t
val of_tail : ('tail, 'element) t -> ((_, 'tail) cons, 'element) t
val within : ('inner, 'element) t -> suffix:('outer, 'inner) Suffix_index.t -> ('outer, 'element) t
Transform an index to find an element within a suffix of the list.
O(n) allocation and work.