2 files changed, 22 insertions, 0 deletions
diff --git a/lib/hMap.ml b/lib/hMap.ml
index cf5d0dfbcd..73cfbd0c71 100644
--- a/lib/hMap.ml
+++ b/lib/hMap.ml
@@ -258,6 +258,10 @@ struct
 
   let max_binding _ = assert false (** Cannot be implemented efficiently *)
 
+  let fold_left _ _ _ = assert false (** Cannot be implemented efficiently *)
+
+  let fold_right _ _ _ = assert false (** Cannot be implemented efficiently *)
+
   let choose s =
     let (_, m) = Int.Map.choose s in
     Map.choose m
@@ -295,4 +299,19 @@ struct
     let m = Map.update k x m in
     Int.Map.update h m s
 
+  let smartmap f s =
+    let fs m = Map.smartmap f m in
+    Int.Map.smartmap fs s
+
+  let smartmapi f s =
+    let fs m = Map.smartmapi f m in
+    Int.Map.smartmap fs s
+
+  module Unsafe =
+  struct
+    let map f s =
+      let fs m = Map.Unsafe.map f m in
+      Int.Map.map fs s
+  end
+
 end
diff --git a/lib/hMap.mli b/lib/hMap.mli
index 4519ba316a..45b722fda0 100644
--- a/lib/hMap.mli
+++ b/lib/hMap.mli
@@ -10,7 +10,10 @@ module type HashedType =
 sig
   type t
   val compare : t -> t -> int
+  (** Total ordering *)
   val hash : t -> int
+  (** Hashing function compatible with [compare], i.e. [compare x y = 0] implies
+      [hash x = hash y]. *)
 end
 
 (** Hash maps are maps that take advantage of having a hash on keys. This is