Sets et Maps avec egalite generique

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@121 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 109 insertions, 0 deletions

diff --git a/lib/gmap.ml b/lib/gmap.ml
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+(* $Id$ *)
+
+(* Maps using the generic comparison function of ocaml. Code borrowed from
+   the ocaml standard library. *)
+
+    type ('a,'b) t =
+        Empty
+      | Node of ('a,'b) t * 'a * 'b * ('a,'b) t * int
+
+    let empty = Empty
+
+    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) as t ->
+          let c = Pervasives.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 = Pervasives.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 = Pervasives.compare x v in
+          c = 0 || mem x (if c < 0 then l else r)
+
+    let rec merge t1 t2 =
+      match (t1, t2) with
+        (Empty, t) -> t
+      | (t, Empty) -> t
+      | (Node(l1, v1, d1, r1, h1), Node(l2, v2, d2, r2, h2)) ->
+          bal l1 v1 d1 (bal (merge r1 l2) v2 d2 r2)
+
+    let rec remove x = function
+        Empty ->
+          Empty
+      | Node(l, v, d, r, h) as t ->
+          let c = Pervasives.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)
+
+    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))