-(* VECCHIA UNIFICAZIONE -- molto piu' bella, alas *)
-(*
-let fo_unif_mgu k t1 t2 mgu =
- let module C = Cic in
- let module R = CicReduction in
- let module S = CicSubstitution in
- let rec deref n = match mgu.(n) with
- C.Meta m as t -> if n = m then t else (deref m)
- | t -> t
- in
- let rec fo_unif k t1 t2 = match (t1, t2) with
- (* aggiungere l'unificazione sui tipi in caso di istanziazione *)
- (C.Meta n, C.Meta m) -> if n == m then () else
- let t1' = deref n in
- let t2' = deref m in
- (* deref of metavariables ARE already delifted *)
- (match (t1',t2') with
- (C.Meta n, C.Meta m) -> if n = m then () else
- if n < m then mgu.(m) <- t1' else
- if n > m then mgu.(n) <- t2'
- | (C.Meta n, _) -> mgu.(n) <- t2'
- | (_, C.Meta m) -> mgu.(m) <- t1'
- | (_,_) -> fo_unif k t1' t2')
- | (C.Meta n, _) -> let t1' = deref n in
- let t2' = try delift k t2
- with Free -> raise UnificationFailed in
- (match t1' with
- C.Meta n -> mgu.(n) <- t2'
- | _ -> fo_unif k t1' t2')
- | (_, C.Meta m) -> let t2' = deref m in
- let t1' = try delift k t1
- with Free -> raise UnificationFailed in
- (match t2' with
- C.Meta m -> mgu.(m) <- t1'
- | _ -> fo_unif k t1' t2')
- | (C.Rel _, _)
- | (_, C.Rel _)
- | (C.Var _, _)
- | (_, C.Var _)
- | (C.Sort _ ,_)
- | (_, C.Sort _)
- | (C.Implicit, _)
- | (_, C.Implicit) -> if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (C.Cast (te,ty), _) -> fo_unif k te t2
- | (_, C.Cast (te,ty)) -> fo_unif k t1 te
- | (C.Prod (_,s1,t1), C.Prod (_,s2,t2)) -> fo_unif k s1 s2;
- fo_unif (k+1) t1 t2
- | (C.Lambda (_,s1,t1), C.Lambda (_,s2,t2)) -> fo_unif k s1 s2;
- fo_unif (k+1) t1 t2
- | (C.LetIn (_,s1,t1), _) -> fo_unif k (S.subst s1 t1) t2
- | (_, C.LetIn (_,s2,t2)) -> fo_unif k t1 (S.subst s2 t2)
- | (C.Appl (h1::l1), C.Appl (h2::l2)) ->
- let lr1 = List.rev l1 in
- let lr2 = List.rev l2 in
- let rec fo_unif_aux = function
- ([],l2) -> ([],l2)
- | (l1,[]) -> (l1,[])
- | ((h1::l1),(h2::l2)) -> fo_unif k h1 h2;
- fo_unif_aux (l1,l2)
- in
- (match fo_unif_aux (lr1, lr2) with
- ([],[]) -> fo_unif k h1 h2
- | ([],l2) -> fo_unif k h1 (C.Appl (h2::List.rev l2))
- | (l1,[]) -> fo_unif k (C.Appl (h1::List.rev l1)) h2
- | (_,_) -> raise Impossible)
- | (C.Const _, _)
- | (_, C.Const _)
- | (C.Abst _, _)
- | (_, C.Abst _)
- | (C.MutInd _, _)
- | (_, C.MutInd _)
- | (C.MutConstruct _, _)
- | (_, C.MutConstruct _) -> print_endline "siamo qui"; flush stdout;
- if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (C.MutCase (_,_,_,outt1,t1,pl1), C.MutCase (_,_,_,outt2,t2,pl2))->
- fo_unif k outt1 outt2;
- fo_unif k t1 t2;
- List.iter2 (fo_unif k) pl1 pl2
- | (C.Fix _, _)
- | (_, C.Fix _)
- | (C.CoFix _, _)
- | (_, C.CoFix _) -> if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (_,_) -> raise UnificationFailed
- in fo_unif k t1 t2;mgu ;;
-*)
-