2 files changed, 9 insertions, 0 deletions
diff --git a/lib/util.ml b/lib/util.ml
index 531e4fe7d6..cfb4ebabc2 100644
--- a/lib/util.ml
+++ b/lib/util.ml
@@ -105,6 +105,11 @@ let app_opt f x =
   | Some f -> f x
   | None -> x
 
+let un_opt x default =
+  match x with
+  | None -> default
+  | Some y -> y
+
 (* Stream *)
 
 let stream_nth n st =
diff --git a/lib/util.mli b/lib/util.mli
index 86720fe471..bcb1b62651 100644
--- a/lib/util.mli
+++ b/lib/util.mli
@@ -89,6 +89,10 @@ val iterate : ('a -> 'a) -> int -> 'a -> 'a
 val repeat : int -> ('a -> unit) -> 'a -> unit
 val app_opt : ('a -> 'a) option -> 'a -> 'a
 
+(** [un_opt opt default] returns the content of [opt] if possible and
+    default otherwise. *)
+val un_opt : 'a option -> 'a -> 'a
+
 (** {6 Delayed computations. } *)
 
 type 'a delayed = unit -> 'a