(* * * * * * * * * * *
 * Resource Aware ML *
 * * * * * * * * * * *
 *
 * * *  Use Cases * *
 *
 * File:
 *   example/list_map.raml
 *
 * Author:
 *   Jan Hoffmann, Shu-Chun Weng (2014)
 *
 * Description:
 *   Some variations of list map.
 *
 *)


(* The usual list map function. *)
let rec map f l =
  match l with
    | [] -> []
    | x::xs ->
      let ys = map f xs in
      (f x)::ys


(* The usual list rev_map function. *)
let map_rev f l =
  let rec rmap l acc =
    match l with
      | [] -> acc
      | x::xs ->
	let acc' = (f x)::acc in
	rmap  xs acc'
  in
  rmap l []


(* Iteratively apply two functional arguments. *)
let map_rev2 f1 f2 l =

  let rec rmap1 l acc =
    match l with
      | [] -> acc
      | x::xs ->
	rmap2 xs ((f1 x) :: acc)

  and rmap2 l acc =
    match l with
      | [] -> acc
      | x::xs ->
	rmap1 xs ((f2 x) :: acc)
  in

  rmap1 l []
;;
()