Use Util.Result.List.split instead of filter_map and concat_map

Signed-off-by: Nathan Rebours <[email protected]>

Author: NathanReb

lib/mdx.ml

@@ -64,13 +64,8 @@ let parse l =
         | `Block rb -> Block.from_raw rb >>= fun b -> Ok (Block b))
       l
   in
-  let errors =
-    Util.List.concat_map (function Ok _ -> [] | Error l -> l) results
-  in
-  let ok =
-    List.filter_map (function Ok x -> Some x | Error _ -> None) results
-  in
-  match errors with [] -> Ok ok | _ -> Error errors
+  let ok, errors = Util.Result.List.split results in
+  match errors with [] -> Ok ok | _ -> Error (List.concat errors)
 
 let parse_lexbuf file_contents syntax l =
   match syntax with

lib/util.ml

@@ -45,6 +45,15 @@ module Result = struct
     let map ~f l =
       fold ~f:(fun acc elm -> f elm >>| fun elm' -> elm' :: acc) ~init:[] l
       >>| List.rev
+
+    let split l =
+      let rec split_rec oks errors l =
+        match l with
+        | [] -> (List.rev oks, List.rev errors)
+        | Ok x :: tl -> split_rec (x :: oks) errors tl
+        | Error x :: tl -> split_rec oks (x :: errors) tl
+      in
+      split_rec [] [] l
   end
 end
 
@@ -95,15 +104,6 @@ module List = struct
       | h :: t -> ( match f h with Some x -> Some x | None -> aux t)
     in
     aux l
-
-  let concat_map f l =
-    let rec aux f acc = function
-      | [] -> List.rev acc
-      | x :: l ->
-          let xs = f x in
-          aux f (List.rev_append xs acc) l
-    in
-    aux f [] l
 end
 
 module Array = struct

lib/util.mli

@@ -36,6 +36,7 @@ module Result : sig
       ('acc, 'err) result
 
     val map : f:('a -> ('b, 'err) result) -> 'a list -> ('b list, 'err) result
+    val split : ('a, 'err) result list -> 'a list * 'err list
   end
 end
 
@@ -50,7 +51,6 @@ end
 
 module List : sig
   val find_map : ('a -> 'b option) -> 'a list -> 'b option
-  val concat_map : ('a -> 'b list) -> 'a list -> 'b list
 end
 
 module String : sig