1 files changed, 28 insertions, 0 deletions
diff --git a/stdlib/set.mli b/stdlib/set.mli
new file mode 100644
index 000000000..4cf37425a
--- /dev/null
+++ b/stdlib/set.mli
@@ -0,0 +1,28 @@
+(* Sets over ordered types *)
+
+module type OrderedType =
+  sig
+    type t
+    val compare: t -> t -> int
+  end
+
+module type S =
+  sig
+    type elt
+    type t
+    val empty: t
+    val is_empty: t -> bool
+    val mem: elt -> t -> bool
+    val add: elt -> t -> t
+    val remove: elt -> t -> t
+    val union: t -> t -> t
+    val inter: t -> t -> t
+    val diff: t -> t -> t
+    val compare: t -> t -> int
+    val equal: t -> t -> bool
+    val iter: (elt -> 'a) -> t -> unit
+    val fold: (elt -> 'a -> 'a) -> t -> 'a -> 'a
+    val elements: t -> elt list
+  end
+
+module Make(Ord: OrderedType): (S with elt = Ord.t)