Remove AbsoluteDOS from the XPath AST.

[tatoo.git] / src / formula.ml

diff --git a/src/formula.ml b/src/formula.ml
index f7eae85..14fd76f 100644 (file)
--- a/src/formula.ml
+++ b/src/formula.ml
@@ -15,18 +15,17 @@
 INCLUDE "utils.ml"
 
 open Format
-type move = [ `Left | `Right ]
-type 'hcons expr =
-  | False | True
-  | Or of 'hcons * 'hcons
-  | And of 'hcons * 'hcons
-  | Atom of (move * bool * State.t)
+type move = [ `Left | `Right | `Epsilon | `Up1 | `Up2 ]
+type 'formula expr =
+  | False
+  | True
+  | Or of 'formula * 'formula
+  | And of 'formula * 'formula
+  | Move of move * bool * State.t
 
 type 'hcons node = {
   pos : 'hcons expr;
   mutable neg : 'hcons;
-  st : StateSet.t * StateSet.t;
-  size: int; (* Todo check if this is needed *)
 }
 
 external hash_const_variant : [> ] -> int = "%identity"
@@ -37,12 +36,12 @@ module rec Node : Hcons.S
   and Data : Hashtbl.HashedType  with type t = Node.t node =
   struct
     type t =  Node.t node
-    let equal x y = x.size == y.size &&
+    let equal x y = (*x.size == y.size &&*)
       match x.pos, y.pos with
       | a,b when a == b -> true
       | Or(xf1, xf2), Or(yf1, yf2)
       | And(xf1, xf2), And(yf1,yf2)  -> (xf1 == yf1) && (xf2 == yf2)
-      | Atom(d1, p1, s1), Atom(d2 ,p2 ,s2) -> d1 == d2 && p1 == p2 && s1 == s2
+      | Move(d1, p1, s1), Move(d2 ,p2 ,s2) -> d1 == d2 && p1 == p2 && s1 == s2
       | _ -> false
 
     let hash f =
@@ -54,21 +53,20 @@ module rec Node : Hcons.S
       | And (f1, f2) ->
         HASHINT3(PRIME3, Uid.to_int f1.Node.id, Uid.to_int f2.Node.id)
 
-      | Atom(d, p, s) -> HASHINT4(PRIME5, hash_const_variant d,vb p,s)
+      | Move(d, p, s) -> HASHINT4(PRIME5, hash_const_variant d,vb p,s)
   end
 
 type t = Node.t
-let hash x = x.Node.key
+let hash x = x.Node.hash
 let uid x = x.Node.id
 let equal = Node.equal
 let expr f = f.Node.node.pos
-let st f = f.Node.node.st
-let size f = f.Node.node.size
+
 let compare f1 f2 = compare f1.Node.id  f2.Node.id
 let prio f =
   match expr f with
     | True | False -> 10
-    | Atom _ -> 8
+    | Move _ -> 8
     | And _ -> 6
     | Or _ -> 1
 
@@ -85,13 +83,16 @@ let rec print ?(parent=false) ppf f =
       (print ppf f1);
       fprintf ppf " %s " Pretty.vee;
       (print ppf f2);
-    | Atom(dir, b, s) ->
+    | Move(dir, b, s) ->
       let _ = flush_str_formatter() in
       let fmt = str_formatter in
         let a_str, d_str =
           match  dir with
           | `Left ->  Pretty.down_arrow, Pretty.subscript 1
           | `Right -> Pretty.down_arrow, Pretty.subscript 2
+          | `Epsilon -> Pretty.epsilon, ""
+          | `Up1 -> Pretty.up_arrow, Pretty.subscript 1
+          | `Up2 -> Pretty.up_arrow, Pretty.subscript 2
         in
         fprintf fmt "%s%s" a_str d_str;
         State.print fmt s;
@@ -107,36 +108,20 @@ let is_true f = (expr f) == True
 let is_false f = (expr f) == False
 
 
-let cons pos neg s1 s2 size1 size2 =
-  let nnode = Node.make { pos = neg; neg = (Obj.magic 0); st = s2; size = size2 } in
-  let pnode = Node.make { pos = pos; neg = nnode ; st = s1; size = size1 } in
+let cons pos neg =
+  let nnode = Node.make { pos = neg; neg = (Obj.magic 0); } in
+  let pnode = Node.make { pos = pos; neg = nnode } in
     (Node.node nnode).neg <- pnode; (* works because the neg field isn't taken into
                                        account for hashing ! *)
     pnode,nnode
 
 
-let empty_pair = StateSet.empty, StateSet.empty
-let true_,false_ = cons True False empty_pair empty_pair 0 0
+let true_,false_ = cons True False
 let atom_ d p s =
-  let si = StateSet.singleton s in
-  let ss = match d with
-    | `Left -> si, StateSet.empty
-    | `Right -> StateSet.empty, si
-  in fst (cons (Atom(d,p,s)) (Atom(d,not p,s)) ss ss 1 1)
+  fst (cons (Move(d,p,s)) (Move(d,not p,s)))
 
 let not_ f = f.Node.node.neg
 
-let union_pair (l1,r1) (l2, r2) =
-  StateSet.union l1 l2,
-  StateSet.union r1 r2
-
-let merge_states f1 f2 =
-  let sp =
-    union_pair (st f1) (st f2)
-  and sn =
-    union_pair (st (not_ f1)) (st (not_ f2))
-  in
-    sp,sn
 
 let order f1 f2 = if uid f1  < uid f2 then f2,f1 else f1,f2
 
@@ -155,10 +140,7 @@ let or_ f1 f2 =
   (* commutativity of | *)
   else
     let f1, f2 = order f1 f2 in
-    let psize = (size f1) + (size f2) in
-    let nsize = (size (not_ f1)) + (size (not_ f2)) in
-    let sp, sn = merge_states f1 f2 in
-      fst (cons (Or(f1,f2)) (And(not_ f1, not_ f2)) sp sn psize nsize)
+      fst (cons (Or(f1,f2)) (And(not_ f1, not_ f2)))
 
 
 let and_ f1 f2 =
@@ -167,12 +149,3 @@ let and_ f1 f2 =
 
 let of_bool = function true -> true_ | false -> false_
 
-
-module Infix = struct
-  let ( +| ) f1 f2 = or_ f1 f2
-
-  let ( *& ) f1 f2 = and_ f1 f2
-
-  let ( *+ ) d s = atom_ d true s
-  let ( *- ) d s = atom_ d false s
-end