- let retrieve = if unify then IDX.DT.retrieve_unifiables
- else IDX.DT.retrieve_generalizations in
- let lcands = retrieve table l in
- let rcands = retrieve table r in
- let f b c =
- let id, dir, l, r, vl =
- match c with
- | (d, (id,Terms.Equation (l,r,ty,_),vl,_))-> id, d, l, r, vl
- |_ -> assert false
- in
- let reverse = (dir = Terms.Left2Right) = b in
- let l, r, proof_rewrite_dir = if reverse then l,r,Terms.Left2Right
- else r,l, Terms.Right2Left in
- (id,proof_rewrite_dir,Terms.Node [ Terms.Leaf B.eqP; ty; l; r ], vl)
- in
- let cands1 = List.map (f true) (IDX.ClauseSet.elements lcands) in
- let cands2 = List.map (f false) (IDX.ClauseSet.elements rcands) in
- let t = Terms.Node [ Terms.Leaf B.eqP; ty; l; r ] in
- let locked_vars = if unify then [] else vl in
- let rec aux = function
- | [] -> None
- | (id2,dir,c,vl1)::tl ->
- try
- let subst,vl1 = Unif.unification (vl@vl1) locked_vars c t in
- let id_t = Terms.Node [ Terms.Leaf B.eqP; ty; r; r ] in
- build_new_clause bag maxvar (fun _ -> true)
- Terms.Superposition id_t subst [] id id2 [2] dir
- with FoUnif.UnificationFailure _ -> aux tl
- in
- aux (cands1 @ cands2)
+ match rewrite_eq ~unify l r ty vl table with
+ | None -> None
+ | Some (id2, dir, subst) ->
+ let id_t = Terms.Node [ Terms.Leaf B.eqP; ty; r; r ] in
+ build_new_clause bag maxvar (fun _ -> true)
+ Terms.Superposition id_t subst [] id id2 [2] dir