-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