X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=inline;f=helm%2Fsoftware%2Fcomponents%2Fng_paramodulation%2Fterms.ml;h=87b4f383bc53bf13885069592eaf896ad9f58a0e;hb=509151febaf7817e5b6ac4bd22a3d9ffa1d9a1be;hp=aefbc01a864ea3a870746f11d7273f27d5eef8ff;hpb=a872dba2b03e27967d5b9b51e950e85967340e52;p=helm.git

diff --git a/helm/software/components/ng_paramodulation/terms.ml b/helm/software/components/ng_paramodulation/terms.ml
index aefbc01a8..87b4f383b 100644
--- a/helm/software/components/ng_paramodulation/terms.ml
+++ b/helm/software/components/ng_paramodulation/terms.ml
@@ -18,7 +18,7 @@ type 'a foterm =
 
 type 'a substitution = (int * 'a foterm) list
 
-type comparison = Lt | Eq | Gt | Incomparable
+type comparison = Lt | Eq | Gt | Incomparable | Invertible
 
 type rule = Superposition | Demodulation
 type direction = Left2Right | Right2Left | Nodir
@@ -46,6 +46,19 @@ type 'a unit_clause =
 
 type 'a passive_clause = int * 'a unit_clause (* weight * equation *)
 
+let is_eq_clause (_,l,_,_) =
+  match l with
+    | Equation _ -> true
+    | Predicate _ -> false
+;;
+
+let vars_of_term t =
+  let rec aux acc = function
+    | Leaf _ -> acc
+    | Var i -> if (List.mem i acc) then acc else i::acc
+    | Node l -> List.fold_left aux acc l
+  in aux [] t
+;;
 
 module OT =
  struct
@@ -57,16 +70,16 @@ module M : Map.S with type key = int
   = Map.Make(OT) 
 
 type 'a bag = int
-              * (('a unit_clause * bool) M.t)
+              * (('a unit_clause * bool * int) M.t)
 
   let add_to_bag (_,lit,vl,proof) (id,bag) =
     let id = id+1 in
     let clause = (id, lit, vl, proof) in
-    let bag = M.add id (clause,false) bag in
+    let bag = M.add id (clause,false,0) bag in
     (id,bag), clause 
    ;;
 
-  let replace_in_bag ((id,_,_,_),_ as cl) (max_id,bag) =
+  let replace_in_bag ((id,_,_,_),_,_ as cl) (max_id,bag) =
     let bag = M.add id cl bag in
       (max_id,bag)
   ;;
@@ -83,6 +96,7 @@ module type Blob =
     val eq : t -> t -> bool
     val compare : t -> t -> int
     val eqP : t
+    val is_eq: t foterm -> (t foterm* t foterm *t foterm) option 
     val pp : t -> string
     type input
     val embed : input -> t foterm