Ported innermost strategy for demodulation from trunk

[helm.git] / helm / software / components / ng_paramodulation / terms.mli

diff --git a/helm/software/components/ng_paramodulation/terms.mli b/helm/software/components/ng_paramodulation/terms.mli
index c49eaff832727d06f200df5bffce38aacb2f5bf4..76eda3717c3f8457810e8d03ff86d4cfbc7f1cd7 100644 (file)
--- a/helm/software/components/ng_paramodulation/terms.mli
+++ b/helm/software/components/ng_paramodulation/terms.mli
@@ -18,14 +18,20 @@ type 'a foterm =
 
 type 'a substitution = (int * 'a foterm) list
 
-type comparison = Lt | Le | Eq | Ge | Gt | Incomparable
+type comparison = Lt | Eq | Gt | Incomparable | Invertible
 
-type rule = SuperpositionRight | SuperpositionLeft | Demodulation
+type rule = Superposition | Demodulation
+
+(* A Discrimination tree is a map: foterm |-> (dir, clause) *)
 type direction = Left2Right | Right2Left | Nodir
+
 type position = int list
 
 type 'a proof =
-  | Exact of 'a
+  | Exact of 'a foterm
+         (* for theorems like T : \forall x. C[x] = D[x] the proof is 
+          * a foterm like (Node [ Leaf T ; Var i ]), while for the Goal
+          * it is just (Var g), i.e. the identity proof *)
   | Step of rule * int * int * direction * position * 'a substitution
          (* rule, eq1, eq2, direction of eq2, position, substitution *)
 
@@ -44,9 +50,52 @@ type 'a unit_clause =
  * varlist
  * 'a proof      (* proof *)
 
-type 'a passive_clause = int * 'a unit_clause (* weight * equation *)
+type 'a clause =
+    int
+    * ('a literal * bool) list (* left hand side of the arrow,
+                                 with flag for selection *)
+    * ('a literal * bool) list (* right hand side of the arrow,
+                                 with flag for selection *)
+    * varlist
+    * 'a proof
+
+type 'a passive_clause = int * 'a clause (* weight * equation *)
+
+val vars_of_term : ?start_acc:int list -> 'a foterm  -> int list
 
 module M : Map.S with type key = int 
 
-type 'a bag = 'a unit_clause M.t
+type 'a bag = int (* max ID  *)
+              * (('a clause * bool * int) M.t)
+
+(* also gives a fresh ID to the clause *)
+    val add_to_bag : 
+          'a clause -> 'a bag ->
+            'a bag * 'a clause
+
+    val replace_in_bag : 
+          'a clause * bool * int -> 'a bag ->
+            'a bag
+
+    val get_from_bag : 
+          int -> 'a bag -> 'a clause * bool * int
+
+    val empty_bag : 'a bag
+
+module type Blob =
+  sig
+    (* Blob is the type for opaque leaves: 
+     * - checking equality should be efficient
+     * - atoms have to be equipped with a total order relation
+     *)
+    type t
+    val eq : t -> t -> bool
+    val compare : t -> t -> int
+    val eqP : t
+    (* TODO: consider taking in input an imperative buffer for Format 
+     *  val pp : Format.formatter -> t -> unit
+     * *)
+    val pp : t -> string
+
+  end