+let names f map l a =
+ let rec aux f i a = function
+ | [] -> f a
+ | Name (n, r) :: tl -> aux (map f i n r) false a tl
+ | _ :: tl -> aux f i a tl
+ in
+ aux f true a l
+
+let rec get_name err f j = function
+ | [] -> err ()
+ | Name (n, r) :: _ when j = 0 -> f n r
+ | Name _ :: tl -> get_name err f (pred j) tl
+ | _ :: tl -> get_name err f j tl
+
+let rec get_names f = function
+ | [] -> f [] []
+ | Name _ as n :: tl ->
+ let f a ns = f a (n :: ns) in get_names f tl
+ | e :: tl ->
+ let f a = f (e :: a) in get_names f tl
+