Monadic `concat_mapm`

2 files changed, 5 insertions, 3 deletions

diff --git a/lib/Utilities.ml b/lib/Utilities.ml
index dcf4417..6f27b30 100644
--- a/lib/Utilities.ml
+++ b/lib/Utilities.ml
@@ -55,7 +55,7 @@ module List = struct
 
   include Generic (ListSequence)
 
-  let concat_map f xs = List.map f xs |> sequence |> Stdlib.Result.map List.concat
+  let concat_mapm f xs = List.map f xs |> sequence |> Stdlib.Result.map List.concat
   let hd_opt = function x :: _ -> Some x | [] -> None
 end
 
@@ -93,6 +93,8 @@ module FingerTree = struct
         match f elem with None -> acc | Some result -> BatFingerTree.snoc acc result)
       BatFingerTree.empty
 
+  let concat_mapm f xs = BatFingerTree.map f xs |> sequence |> Stdlib.Result.map BatFingerTree.append
+
   let concat_map f =
     BatFingerTree.fold_left (fun acc elem -> BatFingerTree.append acc @@ f elem) BatFingerTree.empty
 
diff --git a/lib/Utilities.mli b/lib/Utilities.mli
index 7d41e20..3f0787f 100644
--- a/lib/Utilities.mli
+++ b/lib/Utilities.mli
@@ -12,7 +12,7 @@ end
 module List : sig
   val sequence : ('a, 'b) result list -> ('a list, 'b) result
   val foldm_left : ('a -> 'b -> ('a, 'e) result) -> 'a -> 'b list -> ('a, 'e) result
-  val concat_map : ('a -> ('b list, 'e) result) -> 'a list -> ('b list, 'e) result
+  val concat_mapm : ('a -> ('b list, 'e) result) -> 'a list -> ('b list, 'e) result
   val hd_opt : 'a list -> 'a option
 end
 
@@ -36,7 +36,7 @@ module FingerTree : sig
   val foldm_left : ('a -> 'b -> ('a, 'e) result) -> 'a -> 'b BatFingerTree.t -> ('a, 'e) result
   val join : string BatFingerTree.t -> string -> string
   val filter_map : ('a -> 'b option) -> 'a BatFingerTree.t -> 'b BatFingerTree.t
-  val concat_map : ('a -> ('b BatFingerTree.t, 'e) result) -> 'a BatFingerTree.t -> ('b BatFingerTree.t, 'e) result
+  val concat_mapm : ('a -> ('b BatFingerTree.t, 'e) result) -> 'a BatFingerTree.t -> ('b BatFingerTree.t, 'e) result
 end
 
 module Fun : sig