1 files changed, 133 insertions, 0 deletions
diff --git a/lib/fmap.ml b/lib/fmap.ml
new file mode 100644
index 00000000..8ca56fe7
--- /dev/null
+++ b/lib/fmap.ml
@@ -0,0 +1,133 @@
+
+module Make = functor (X:Map.OrderedType) -> struct
+  type key = X.t
+  type 'a t =
+        Empty
+      | Node of 'a t * key * 'a * 'a t * int
+
+    let empty = Empty
+
+    let is_empty = function Empty -> true | _ -> false
+
+    let height = function
+        Empty -> 0
+      | Node(_,_,_,_,h) -> h
+
+    let create l x d r =
+      let hl = height l and hr = height r in
+      Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))
+
+    let bal l x d r =
+      let hl = match l with Empty -> 0 | Node(_,_,_,_,h) -> h in
+      let hr = match r with Empty -> 0 | Node(_,_,_,_,h) -> h in
+      if hl > hr + 2 then begin
+        match l with
+          Empty -> invalid_arg "Map.bal"
+        | Node(ll, lv, ld, lr, _) ->
+            if height ll >= height lr then
+              create ll lv ld (create lr x d r)
+            else begin
+              match lr with
+                Empty -> invalid_arg "Map.bal"
+              | Node(lrl, lrv, lrd, lrr, _)->
+                  create (create ll lv ld lrl) lrv lrd (create lrr x d r)
+            end
+      end else if hr > hl + 2 then begin
+        match r with
+          Empty -> invalid_arg "Map.bal"
+        | Node(rl, rv, rd, rr, _) ->
+            if height rr >= height rl then
+              create (create l x d rl) rv rd rr
+            else begin
+              match rl with
+                Empty -> invalid_arg "Map.bal"
+              | Node(rll, rlv, rld, rlr, _) ->
+                  create (create l x d rll) rlv rld (create rlr rv rd rr)
+            end
+      end else
+        Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))
+
+    let rec add x data = function
+        Empty ->
+          Node(Empty, x, data, Empty, 1)
+      | Node(l, v, d, r, h) ->
+          let c = X.compare x v in
+          if c = 0 then
+            Node(l, x, data, r, h)
+          else if c < 0 then
+            bal (add x data l) v d r
+          else
+            bal l v d (add x data r)
+
+    let rec find x = function
+        Empty ->
+          raise Not_found
+      | Node(l, v, d, r, _) ->
+          let c = X.compare x v in
+          if c = 0 then d
+          else find x (if c < 0 then l else r)
+
+    let rec mem x = function
+        Empty ->
+          false
+      | Node(l, v, d, r, _) ->
+          let c = X.compare x v in
+          c = 0 || mem x (if c < 0 then l else r)
+
+    let rec min_binding = function
+        Empty -> raise Not_found
+      | Node(Empty, x, d, r, _) -> (x, d)
+      | Node(l, x, d, r, _) -> min_binding l
+
+    let rec remove_min_binding = function
+        Empty -> invalid_arg "Map.remove_min_elt"
+      | Node(Empty, x, d, r, _) -> r
+      | Node(l, x, d, r, _) -> bal (remove_min_binding l) x d r
+
+    let merge t1 t2 =
+      match (t1, t2) with
+        (Empty, t) -> t
+      | (t, Empty) -> t
+      | (_, _) ->
+          let (x, d) = min_binding t2 in
+          bal t1 x d (remove_min_binding t2)
+
+    let rec remove x = function
+        Empty ->
+          Empty
+      | Node(l, v, d, r, h) ->
+          let c = X.compare x v in
+          if c = 0 then
+            merge l r
+          else if c < 0 then
+            bal (remove x l) v d r
+          else
+            bal l v d (remove x r)
+
+    let rec iter f = function
+        Empty -> ()
+      | Node(l, v, d, r, _) ->
+          iter f l; f v d; iter f r
+
+    let rec map f = function
+        Empty               -> Empty
+      | Node(l, v, d, r, h) -> Node(map f l, v, f d, map f r, h)
+
+    (* Maintien de fold_right par compatibilité (changé en fold_left dans
+       ocaml-3.09.0) *)
+
+    let rec fold f m accu =
+      match m with
+        Empty -> accu
+      | Node(l, v, d, r, _) ->
+          fold f l (f v d (fold f r accu))
+
+(* Added with respect to ocaml standard library. *)
+
+    let dom m = fold (fun x _ acc -> x::acc) m []
+
+    let rng m = fold (fun _ y acc -> y::acc) m []
+
+    let to_list m = fold (fun x y acc -> (x,y)::acc) m []
+
+end