1 files changed, 26 insertions, 20 deletions

diff --git a/lib/dyn.ml b/lib/dyn.ml
index 056b68731..826cfaf8d 100644
--- a/lib/dyn.ml
+++ b/lib/dyn.ml
@@ -6,12 +6,24 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
-open Errors
-open Pp
-
+module type S =
+sig
+type 'a tag
+type t = Dyn : 'a tag * 'a -> t
+
+val create : string -> 'a tag
+val eq : 'a tag -> 'b tag -> ('a, 'b) CSig.eq option
+val repr : 'a tag -> string
+val dump : unit -> (int * string) list
+end
+
+module Make(M : CSig.EmptyS) =
+struct
 (* Dynamics, programmed with DANGER !!! *)
 
-type t = int * Obj.t
+type 'a tag = int
+
+type t = Dyn : 'a tag * 'a -> t
 
 let dyntab = ref (Int.Map.empty : string Int.Map.t)
 (** Instead of working with tags as strings, which are costly, we use their
@@ -24,27 +36,21 @@ let create (s : string) =
   let () =
     if Int.Map.mem hash !dyntab then
       let old = Int.Map.find hash !dyntab in
-      let msg = str "Dynamic tag collision: " ++ str s ++ str " vs. " ++ str old in
-      anomaly ~label:"Dyn.create" msg
+      let () = Printf.eprintf "Dynamic tag collision: %s vs. %s\n%!" s old in
+      assert false
   in
   let () = dyntab := Int.Map.add hash s !dyntab in
-  let infun v = (hash, Obj.repr v) in
-  let outfun (nh, rv) =
-    if Int.equal hash nh then Obj.magic rv
-    else
-      anomaly (str "dyn_out: expected " ++ str s)
-  in
-  (infun, outfun)
+  hash
 
-let has_tag (s, _) tag =
-  let hash = Hashtbl.hash (tag : string) in
-  Int.equal s hash
+let eq : 'a 'b. 'a tag -> 'b tag -> ('a, 'b) CSig.eq option =
+  fun h1 h2 -> if Int.equal h1 h2 then Some (Obj.magic CSig.Refl) else None
 
-let tag (s,_) =
+let repr s =
   try Int.Map.find s !dyntab
   with Not_found ->
-    anomaly (str "Unknown dynamic tag " ++ int s)
-
-let pointer_equal (t1,o1) (t2,o2) = t1 = t2 && o1 == o2
+    let () = Printf.eprintf "Unknown dynamic tag %i\n%!" s in
+    assert false
 
 let dump () = Int.Map.bindings !dyntab
+
+end
\ No newline at end of file