Merge branch 'handle-stdout'

[SXSI/xpathcomp.git] / src / formula.ml

diff --git a/src/formula.ml b/src/formula.ml
index 16db6d5..4690ee0 100644 (file)
--- a/src/formula.ml
+++ b/src/formula.ml
@@ -6,13 +6,13 @@ type 'hcons expr =
   | False | True
   | Or of 'hcons * 'hcons
   | And of 'hcons * 'hcons
-  | Atom of ([ `Left | `Right ] * bool * State.t)
+  | Atom of ([ `Left | `Right | `Epsilon ] * bool * State.t)
   | Pred of Tree.Predicate.t
 
 type 'hcons node = {
   pos : 'hcons expr;
   mutable neg : 'hcons;
-  st : (StateSet.t*StateSet.t*StateSet.t)*(StateSet.t*StateSet.t*StateSet.t);
+  st : StateSet.t * StateSet.t;
   size: int; (* Todo check if this is needed *)
 }
 
@@ -78,6 +78,7 @@ let rec print ?(parent=false) ppf f =
          match  dir with
            | `Left ->  Pretty.down_arrow, Pretty.subscript 1
            | `Right -> Pretty.down_arrow, Pretty.subscript 2
+           | `Epsilon -> Pretty.epsilon, ""
        in
          fprintf fmt "%s%s" a_str d_str;
          State.print fmt s;
@@ -101,31 +102,33 @@ let cons pos neg s1 s2 size1 size2 =
                                      account for hashing ! *)
     pnode,nnode
 
-let empty_triple = StateSet.empty,StateSet.empty,StateSet.empty
-let empty_hex = empty_triple,empty_triple
-let true_,false_ = cons True False empty_hex empty_hex 0 0
+
+let empty_pair = StateSet.empty, StateSet.empty
+let true_,false_ = cons True False empty_pair empty_pair 0 0
 let atom_ d p s =
   let si = StateSet.singleton s in
   let ss = match d with
-    | `Left -> (si,StateSet.empty,si),empty_triple
-    | `Right -> empty_triple,(si,StateSet.empty,si)
+    | `Left -> si, StateSet.empty
+    | `Right -> StateSet.empty, si
+    | `Epsilon -> empty_pair (* TODO CHECK *)
   in fst (cons (Atom(d,p,s)) (Atom(d,not p,s)) ss ss 1 1)
 
 let pred_ p =
   let fneg = !(p.Tree.Predicate.node) in
   let pneg = Tree.Predicate.make (ref (fun t n -> not (fneg t n))) in
-  fst (cons (Pred p) (Pred pneg) empty_hex empty_hex 1 1)
+  fst (cons (Pred p) (Pred pneg) empty_pair empty_pair 1 1)
 
 let not_ f = f.Node.node.neg
-let union_hex  ((l1,ll1,lll1),(r1,rr1,rrr1))  ((l2,ll2,lll2),(r2,rr2,rrr2)) =
-  (StateSet.mem_union l1 l2 ,StateSet.mem_union ll1 ll2,StateSet.mem_union lll1 lll2),
-  (StateSet.mem_union r1 r2 ,StateSet.mem_union rr1 rr2,StateSet.mem_union rrr1 rrr2)
+
+let union_pair (l1,r1) (l2, r2) =
+  StateSet.mem_union l1 l2,
+  StateSet.mem_union r1 r2
 
 let merge_states f1 f2 =
   let sp =
-    union_hex (st f1) (st f2)
+    union_pair (st f1) (st f2)
   and sn =
-    union_hex (st (not_ f1)) (st (not_ f2))
+    union_pair (st (not_ f1)) (st (not_ f2))
   in
     sp,sn
 
@@ -141,7 +144,7 @@ let or_ f1 f2 =
   else if is_true f1 || is_true f2 then true_
   else if is_false f1 && is_false f2 then false_
   else if is_false f1 then f2
-  else if is_false f2 then f1 
+  else if is_false f2 then f1
 
              (* commutativity of | *)
   else