functorial abstraction over term blobs

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

diff --git a/helm/software/components/ng_paramodulation/terms.ml b/helm/software/components/ng_paramodulation/terms.ml
index 91ca56271404a9e9ccb2cd9df6ee37fa99e8a81b..8fad7187b958c089a1051dbae59f34027777e775 100644 (file)
--- a/helm/software/components/ng_paramodulation/terms.ml
+++ b/helm/software/components/ng_paramodulation/terms.ml
@@ -57,3 +57,70 @@ module M : Map.S with type key = int
   = Map.Make(OT) 
 
 type 'a bag = 'a unit_clause M.t
+
+module type Blob =
+  sig
+    type t
+    val eq : t -> t -> bool
+    val compare : t -> t -> int
+    val pp : t -> string
+  end
+
+module Utils (B : Blob) = struct
+  let rec eq_foterm x y =
+    x == y ||
+    match x, y with
+    | Leaf t1, Leaf t2 -> B.eq t1 t2
+    | Var i, Var j -> i = j
+    | Node l1, Node l2 -> List.for_all2 eq_foterm l1 l2
+    | _ -> false
+  ;;
+
+  let rec lexicograph f l1 l2 =
+    match l1, l2 with
+    | [], [] -> 0
+    | x::xs, y::ys ->
+       let c = f x y in
+       if c <> 0 then c else lexicograph f xs ys
+    | [],_ -> ~-1
+    | _,[] -> 1
+  ;;
+
+  let rec compare_foterm x y =
+    match x, y with
+    | Leaf t1, Leaf t2 -> B.compare t1 t2
+    | Var i, Var j -> i - j
+    | Node l1, Node l2 -> lexicograph compare_foterm l1 l2
+    | Leaf _, ( Node _ | Var _ ) -> ~-1
+    | Node _, Leaf _ -> 1
+    | Node _, Var _ -> ~-1
+    | Var _, _ ->  1
+  ;;
+
+  let eq_literal l1 l2 =
+    match l1, l2 with
+    | Predicate p1, Predicate p2 -> eq_foterm p1 p2
+    | Equation (l1,r1,ty1,o1), Equation (l2,r2,ty2,o2) ->
+        o1 = o2 && eq_foterm l1 l2 && eq_foterm r1 r2 && eq_foterm ty1 ty2
+    | _ -> false
+  ;;
+
+  let compare_literal l1 l2 =
+    match l1, l2 with
+    | Predicate p1, Predicate p2 -> compare_foterm p1 p2
+    | Equation (l1,r1,ty1,o1), Equation (l2,r2,ty2,o2) ->
+        let c = Pervasives.compare o1 o2 in
+        if c <> 0 then c else
+          let c = compare_foterm l1 l2 in
+          if c <> 0 then c else
+            let c = compare_foterm r1 r2 in
+            if c <> 0 then c else
+              compare_foterm ty1 ty2
+    | Predicate _, Equation _ -> ~-1
+    | Equation _, Predicate _ -> 1
+  ;;
+
+  let eq_unit_clause (id1,_,_,_) (id2,_,_,_) = id1 = id2
+  let compare_unit_clause (id1,_,_,_) (id2,_,_,_) = Pervasives.compare id1 id2
+
+end