unikernel/duniverse/dune_/otherlibs/stdune/src/id.ml

@@ -0,0 +1,30 @@
+module type S = sig
+  type t [@@immediate]
+
+  include Comparable_intf.S with type key := t
+  module Table : Hashtbl.S with type key = t
+
+  val gen : unit -> t
+  val peek : unit -> t
+  val to_int : t -> int
+  val compare : t -> t -> Ordering.t
+  val equal : t -> t -> bool
+  val hash : t -> int
+  val to_dyn : t -> Dyn.t
+end
+
+module Make () : S = struct
+  include Int
+  module Table = Hashtbl.Make (Int)
+
+  let next = ref 0
+
+  let gen () =
+    let v = !next in
+    next := v + 1;
+    v
+  ;;
+
+  let peek () = !next
+  let to_int x = x
+end