2 files changed, 5 insertions, 0 deletions
diff --git a/lib/Utilities.ml b/lib/Utilities.ml
index e4ee9c3..9bff69b 100644
--- a/lib/Utilities.ml
+++ b/lib/Utilities.ml
@@ -39,6 +39,10 @@ module List = struct
   end
 
   include Generic (ListSequence)
+
+  let hd_opt = function
+    | x::_ -> Some x
+    | [] -> None
 end
 
 module FingerTree = struct
diff --git a/lib/Utilities.mli b/lib/Utilities.mli
index f149889..eae59f9 100644
--- a/lib/Utilities.mli
+++ b/lib/Utilities.mli
@@ -11,6 +11,7 @@ end
 
 module List : sig
   val sequence : ('a, 'b) result list -> ('a list, 'b) result
+  val hd_opt : 'a list -> 'a option
 end
 
 module Option : sig