X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_refiner%2FnCicUnification.ml;h=fcc76b0adc5bf72b38129bd36a3ddca7952d4676;hb=258d2e384e8bf7008d2fb01c7d3fee5126d65120;hp=7bec66a77fee305635b0dd6a671762c2c19c67b9;hpb=57c897b886b3cc52c62589b4a6e0b32566c6758a;p=helm.git diff --git a/helm/software/components/ng_refiner/nCicUnification.ml b/helm/software/components/ng_refiner/nCicUnification.ml index 7bec66a77..fcc76b0ad 100644 --- a/helm/software/components/ng_refiner/nCicUnification.ml +++ b/helm/software/components/ng_refiner/nCicUnification.ml @@ -50,7 +50,7 @@ let eta_reduce subst t = let _,_,t,_ = NCicUtils.lookup_subst i subst in let t = NCicSubstitution.subst_meta lc t in eat_lambdas ctx t - with Not_found -> ctx, t) + with NCicUtils.Subst_not_found _ -> ctx, t) | t -> ctx, t in let context_body = eat_lambdas [] t in @@ -91,14 +91,16 @@ let inside c = prerr_endline ("{{{" ^ !indent ^ " ") end ;; -let outside ok = +let outside exc_opt = if !debug then begin let time2 = Unix.gettimeofday () in let time1 = match !times with time1::tl -> times := tl; time1 | [] -> assert false in - prerr_endline ("}}} " ^ string_of_float (time2 -. time1)); - if not ok then prerr_endline "exception raised!"; + prerr_endline ("}}} " ^ !indent ^ " " ^ string_of_float (time2 -. time1)); + (match exc_opt with + | Some e -> prerr_endline ("exception raised: " ^ Printexc.to_string e) + | None -> ()); try indent := String.sub !indent 0 (String.length !indent -1) with @@ -113,26 +115,8 @@ let ppmetasenv ~subst m = "\nmenv:\n" ^ NCicPp.ppmetasenv ~subst m;; let ppcontext ~metasenv:_metasenv ~subst:_subst _context = "";; let ppmetasenv ~subst:_subst _metasenv = "";; - -let fix_sorts swap exc t = - let rec aux () = function - | NCic.Sort (NCic.Type u) as orig -> - if swap then - match NCicEnvironment.sup u with - | None -> - prerr_endline ("no sup for " ^ NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] orig) ; - raise exc - | Some u1 -> if u = u1 then orig else NCic.Sort (NCic.Type u1) - else - NCic.Sort (NCic.Type ( - match NCicEnvironment.sup NCicEnvironment.type0 with - | Some x -> x - | _ -> assert false)) - | NCic.Meta _ as orig -> orig - | t -> NCicUtils.map (fun _ _ -> ()) () aux t - in - aux () t -;; +let ppterm ~metasenv ~subst ~context = NCicPp.ppterm ~metasenv ~subst ~context;; +(* let ppterm ~metasenv:_ ~subst:_ ~context:_ _ = "";; *) let is_locked n subst = try @@ -159,247 +143,309 @@ let rec could_reduce = | C.Appl [] | C.LetIn _ | C.Implicit _ -> assert false ;; -let rec lambda_intros rdb metasenv subst context t args = - let tty = NCicTypeChecker.typeof ~metasenv ~subst context t in - let argsty = - List.map - (fun arg -> arg, NCicTypeChecker.typeof ~metasenv ~subst context arg) args in - let context_of_args = context in - let rec mk_lambda metasenv subst context n processed_args = function - | [] -> +let rec lambda_intros rdb metasenv subst context argsno ty = + pp (lazy ("LAMBDA INTROS: " ^ ppterm ~metasenv ~subst ~context ty)); + match argsno with + 0 -> let metasenv, _, bo, _ = - NCicMetaSubst.mk_meta metasenv context - (`WithType (NCicSubstitution.lift n tty)) - in - metasenv, subst, bo - | (arg,ty)::tail -> - pp(lazy("arg{ " ^ - NCicPp.ppterm ~metasenv ~subst ~context:context_of_args arg ^ " : " ^ - NCicPp.ppterm ~metasenv ~subst ~context:context_of_args ty)); - let metasenv, subst, telescopic_ty = - if processed_args = [] then metasenv, subst, ty else - let _ = pp(lazy("delift")) in - delift_type_wrt_terms rdb metasenv subst context - (NCicSubstitution.lift n ty) - (List.map (NCicSubstitution.lift n) (List.rev processed_args)) - in - pp(lazy("arg} "^NCicPp.ppterm ~metasenv ~subst ~context telescopic_ty)); - let name = "HBeta"^string_of_int n in - let metasenv, subst, bo = - mk_lambda metasenv subst ((name,NCic.Decl telescopic_ty)::context) (n+1) - (arg::processed_args) tail - in - metasenv, subst, NCic.Lambda (name, telescopic_ty, bo) - in - pp(lazy("LAMBDA_INTROS{ " ^ - NCicPp.ppterm ~metasenv ~subst ~context t ^ ":" ^ - NCicPp.ppterm ~metasenv ~subst ~context tty ^ " over " ^ - String.concat "," (List.map (NCicPp.ppterm ~metasenv ~subst ~context)args))); - let rc = mk_lambda metasenv subst context 0 [] argsty in - pp(lazy("LAMBDA_INTROS}")); - rc - -and instantiate rdb test_eq_only metasenv subst context n lc t swap = - (*D*) inside 'I'; try let rc = - pp (lazy(string_of_int n ^ " :=?= "^ - NCicPp.ppterm ~metasenv ~subst ~context t)); - let unify test_eq_only m s c t1 t2 = - if swap then unify rdb test_eq_only m s c t2 t1 - else unify rdb test_eq_only m s c t1 t2 - in - let has_tag = List.exists in - let tags, _, ty = NCicUtils.lookup_meta n metasenv in - (* on the types *) - let metasenv, subst, t = - match ty with - | NCic.Implicit (`Typeof _) -> - pp(lazy("meta with no type")); - assert(has_tag ((=)`IsSort) tags); - metasenv, subst, t - | _ -> - let exc_to_be = - UnificationFailure (mk_msg metasenv subst context (NCic.Meta (n,lc)) t) + NCicMetaSubst.mk_meta metasenv context ~with_type:ty `IsTerm in - let t, ty_t = - try t, NCicTypeChecker.typeof ~subst ~metasenv context t - with - | NCicTypeChecker.AssertFailure msg as exn -> - pp(lazy("we try to fix the sort\n"^ - Lazy.force msg^"\n"^NCicPp.ppmetasenv ~subst metasenv)); - let ft = fix_sorts swap exc_to_be t in - pp(lazy("unable to fix the sort")); - if ft == t then raise exn; - (try ft, NCicTypeChecker.typeof ~subst ~metasenv context ft - with NCicTypeChecker.AssertFailure _ -> raise exn) - | NCicTypeChecker.TypeCheckerFailure msg -> - prerr_endline (Lazy.force msg); - prerr_endline (NCicPp.ppterm ~metasenv ~subst ~context t); - prerr_endline (ppcontext ~metasenv ~subst context); - prerr_endline (ppmetasenv ~subst metasenv); - assert false - in - match ty_t with - | NCic.Implicit (`Typeof _) -> - raise (UnificationFailure(lazy "trying to unify a term with a type")) - | _ -> - let lty = NCicSubstitution.subst_meta lc ty in - pp (lazy ("On the types: " ^ - NCicPp.ppterm ~metasenv ~subst ~context lty ^ " === " ^ - NCicPp.ppterm ~metasenv ~subst ~context ty_t)); - let metasenv,subst = - try unify test_eq_only metasenv subst context lty ty_t - with NCicEnvironment.BadConstraint _ as exc -> - let ty_t = fix_sorts swap exc_to_be ty_t in - try unify test_eq_only metasenv subst context lty ty_t - with - | NCicEnvironment.BadConstraint _ - | UnificationFailure _ -> raise exc + metasenv, bo + | _ -> + (match NCicReduction.whd ~subst context ty with + C.Prod (n,so,ta) -> + let metasenv,bo = + lambda_intros rdb metasenv subst + ((n,C.Decl so)::context) (argsno - 1) ta in - metasenv, subst, t - in - (* viral sortification *) - let is_sort metasenv subst context t = - match NCicReduction.whd ~subst context t with - | NCic.Meta (i,_) -> - let tags, _, _ = NCicUtils.lookup_meta i metasenv in - has_tag ((=) `IsSort) tags - | NCic.Sort _ -> true - | _ -> false - in - let rec sortify metasenv subst = function - | NCic.Implicit (`Typeof _) -> assert false - | NCic.Sort _ as t -> metasenv, subst, t, 0 - | NCic.Meta (i,_) as t -> - let tags, context, ty = NCicUtils.lookup_meta i metasenv in - if has_tag ((=) `IsSort) tags then metasenv, subst, t, i - else - let ty = NCicReduction.whd ~subst context ty in - let metasenv, subst, ty, _ = sortify metasenv subst ty in - let metasenv, j, m, _ = - NCicMetaSubst.mk_meta metasenv ~attrs:[`IsSort] [] (`WithType ty) - in - pp(lazy("rimpiazzo " ^ string_of_int i^" con "^string_of_int j)); - let subst_entry = i, (tags, context, m, ty) in - let subst = subst_entry :: subst in - let metasenv = List.filter (fun x,_ -> i <> x) metasenv in - metasenv, subst, m, j - | NCic.Appl (NCic.Meta _ as hd :: args) as t -> - let metasenv, subst, lambda_Mj = - lambda_intros rdb metasenv subst context t args - in - let metasenv,subst= unify true metasenv subst context hd lambda_Mj in - let t = NCicReduction.whd ~subst context t in - let _result = sortify metasenv subst t in - (* untested, maybe dead, code *) assert false; - | t -> - if could_reduce t then raise (Uncertain(lazy "not a sort")) - else raise (UnificationFailure(lazy "not a sort")) - in - let metasenv, subst, _, n = - if has_tag ((=) `IsSort) tags then - let m,s,x,_ = sortify metasenv subst (NCicReduction.whd ~subst context t) - in m,s,x,n - else if is_sort metasenv subst context t then - sortify metasenv subst (NCic.Meta (n,lc)) - else - metasenv, subst, NCic.Rel ~-1,n + metasenv,C.Lambda (n,so,bo) + | _ -> assert false) +;; + +let unopt exc = function None -> raise exc | Some x -> x ;; + +let fix metasenv subst is_sup test_eq_only exc t = + (*D*) inside 'f'; try let rc = + pp (lazy (NCicPp.ppterm ~metasenv ~subst ~context:[] t)); + let rec aux test_eq_only metasenv = function + | NCic.Prod (n,so,ta) -> + let metasenv,so = aux true metasenv so in + let metasenv,ta = aux test_eq_only metasenv ta in + metasenv,NCic.Prod (n,so,ta) + | NCic.Sort (NCic.Type [(`CProp|`Type),_]) as orig when test_eq_only -> + metasenv,orig + | NCic.Sort (NCic.Type _) when test_eq_only -> raise exc + | NCic.Sort (NCic.Type u) when is_sup -> + metasenv, NCic.Sort (NCic.Type (unopt exc (NCicEnvironment.sup u))) + | NCic.Sort (NCic.Type u) -> + metasenv, NCic.Sort (NCic.Type + (unopt exc (NCicEnvironment.inf ~strict:false u))) + | NCic.Meta (n,_) as orig -> + (try + let _,_,_,_ = NCicUtils.lookup_subst n subst in metasenv,orig + with NCicUtils.Subst_not_found _ -> + let metasenv, _ = NCicMetaSubst.extend_meta metasenv n in + metasenv, orig) + | t -> + NCicUntrusted.map_term_fold_a (fun _ x -> x) test_eq_only aux metasenv t in - let tags, ctx, ty = NCicUtils.lookup_meta n metasenv in - (* instantiation *) - pp (lazy(string_of_int n ^ " := 111 = "^ - NCicPp.ppterm ~metasenv ~subst ~context t)); - let (metasenv, subst), t = - try - NCicMetaSubst.delift - ~unify:(fun m s c t1 t2 -> - let ind = !indent in - let res = - try Some (unify test_eq_only m s c t1 t2 ) - with UnificationFailure _ | Uncertain _ -> None + aux test_eq_only metasenv t + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn +;; + +let metasenv_to_subst n (kind,context,ty) metasenv subst = + let infos,metasenv = List.partition (fun (n',_) -> n = n') metasenv in + let attrs,octx,oty = match infos with [_,infos] -> infos | _ -> assert false in + if octx=context && oty=ty then + (n,(NCicUntrusted.set_kind kind attrs, octx, oty))::metasenv,subst + else + let metasenv, _, bo, _ = + NCicMetaSubst.mk_meta metasenv context ~attrs ~with_type:ty kind in + let subst = (n,(NCicUntrusted.set_kind kind attrs,octx,bo,oty))::subst in + metasenv,subst +;; + +let rec sortfy exc metasenv subst context t = + let t = NCicReduction.whd ~subst context t in + let metasenv,subst = + match t with + | NCic.Sort _ -> metasenv, subst + | NCic.Meta (n,_) -> + let attrs, context, ty = NCicUtils.lookup_meta n metasenv in + let kind = NCicUntrusted.kind_of_meta attrs in + if kind = `IsSort then + metasenv,subst + else + (match ty with + | NCic.Implicit (`Typeof _) -> + metasenv_to_subst n (`IsSort,[],ty) metasenv subst + | ty -> + let metasenv,subst,ty = sortfy exc metasenv subst context ty in + metasenv_to_subst n (`IsSort,[],ty) metasenv subst) + | NCic.Implicit _ -> assert false + | _ -> raise exc + in + metasenv,subst,t + +let tipify exc metasenv subst context t ty = + let is_type attrs = + match NCicUntrusted.kind_of_meta attrs with + `IsType | `IsSort -> true + | `IsTerm -> false + in + let rec optimize_meta metasenv subst = + function + NCic.Meta (n,lc) -> + (try + let attrs,_,_ = NCicUtils.lookup_meta n metasenv in + if is_type attrs then + metasenv,subst,true + else + let _,cc,ty = NCicUtils.lookup_meta n metasenv in + let metasenv,subst,ty = sortfy exc metasenv subst cc ty in + let metasenv = + NCicUntrusted.replace_in_metasenv n + (fun attrs,cc,_ -> NCicUntrusted.set_kind `IsType attrs, cc, ty) + metasenv in - indent := ind; res) - metasenv subst context n lc t - with NCicMetaSubst.Uncertain msg -> - pp (lazy ("delift fails: " ^ Lazy.force msg)); - raise (Uncertain msg) - | NCicMetaSubst.MetaSubstFailure msg -> - pp (lazy ("delift fails: " ^ Lazy.force msg)); - raise (UnificationFailure msg) + metasenv,subst,false + with + NCicUtils.Meta_not_found _ -> + let attrs, _,bo,_ = NCicUtils.lookup_subst n subst in + if is_type attrs then + metasenv,subst,true + else + let _,cc,_,ty = NCicUtils.lookup_subst n subst in + let metasenv,subst,ty = sortfy exc metasenv subst cc ty in + let subst = + NCicUntrusted.replace_in_subst n + (fun attrs,cc,bo,_->NCicUntrusted.set_kind `IsType attrs,cc,bo,ty) + subst + in + optimize_meta metasenv subst (NCicSubstitution.subst_meta lc bo)) + | _ -> metasenv,subst,false + in + let metasenv,subst,b = optimize_meta metasenv subst t in + if b then + metasenv,subst,t + else + let metasenv,subst,_ = sortfy exc metasenv subst context ty in + metasenv,subst,t +;; + +let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = + (*D*) inside 'I'; try let rc = + pp (lazy(string_of_int n^" :=?= "^ppterm ~metasenv ~subst ~context t)); + let exc = + UnificationFailure (mk_msg metasenv subst context (NCic.Meta (n,lc)) t) in + let move_to_subst i ((_,cc,t,_) as infos) metasenv subst = + let metasenv = List.remove_assoc i metasenv in + pp(lazy(string_of_int n ^ " :==> "^ ppterm ~metasenv ~subst ~context:cc t)); + metasenv, (i,infos) :: subst in - pp (lazy(string_of_int n ^ " := 222 = "^ - NCicPp.ppterm ~metasenv ~subst ~context:ctx t - ^ ppmetasenv ~subst metasenv)); - (* Unifying the types may have already instantiated n. *) - try - let _, _,oldt,_ = NCicUtils.lookup_subst n subst in - let oldt = NCicSubstitution.subst_meta lc oldt in - let t = NCicSubstitution.subst_meta lc t in - (* conjecture: always fail --> occur check *) - unify test_eq_only metasenv subst context oldt t - with NCicUtils.Subst_not_found _ -> - let metasenv, tags = - let rec aux = function - | NCic.Meta (j,lc) -> - (try - let _, _, t, _ = NCicUtils.lookup_subst j subst in - aux (NCicSubstitution.subst_meta lc t) - with NCicUtils.Subst_not_found _ -> - let tags', ctx, ty = NCicUtils.lookup_meta j metasenv in - let metasenv = List.remove_assoc j metasenv in - let tags = tags @ tags' in - (j, (tags, ctx, ty)) :: metasenv, tags) - | _ -> metasenv, tags - in - aux t - in - (* by cumulativity when unify(?,Type_i) - * we could ? := Type_j with j <= i... *) - let subst = (n, (tags, ctx, t, ty)) :: subst in - pp (lazy ("?"^string_of_int n^" := "^NCicPp.ppterm - ~metasenv ~subst ~context (NCicSubstitution.subst_meta lc t))); - let metasenv = - List.filter (fun (m,_) -> not (n = m)) metasenv + let delift_to_subst test_eq_only n lc (attrs,cc,ty) t context metasenv subst = + pp (lazy(string_of_int n ^ " := 111 = "^ + ppterm ~metasenv ~subst ~context t)); + let (metasenv, subst), t = + try + NCicMetaSubst.delift + ~unify:(fun m s c t1 t2 -> + let ind = !indent in + let res = + try Some (unify rdb test_eq_only m s c t1 t2 false) + with UnificationFailure _ | Uncertain _ -> None + in + indent := ind; res) + metasenv subst context n lc t + with NCicMetaSubst.Uncertain msg -> + pp (lazy ("delift is uncertain: " ^ Lazy.force msg)); + raise (Uncertain msg) + | NCicMetaSubst.MetaSubstFailure msg -> + pp (lazy ("delift fails: " ^ Lazy.force msg)); + raise (UnificationFailure msg) in - metasenv, subst - (*D*) in outside true; rc with exn -> outside false; raise exn + pp (lazy(string_of_int n ^ " := 222 = "^ + ppterm ~metasenv ~subst ~context:cc t^ppmetasenv ~subst metasenv)); + (* Unifying the types may have already instantiated n. *) + try + let _, _,oldt,_ = NCicUtils.lookup_subst n subst in + let oldt = NCicSubstitution.subst_meta lc oldt in + let t = NCicSubstitution.subst_meta lc t in + (* conjecture: always fail --> occur check *) + unify rdb test_eq_only metasenv subst context t oldt false + with NCicUtils.Subst_not_found _ -> + move_to_subst n (attrs,cc,t,ty) metasenv subst + in + let attrs,cc,ty = NCicUtils.lookup_meta n metasenv in + let kind = NCicUntrusted.kind_of_meta attrs in + let metasenv,t = fix metasenv subst swap test_eq_only exc t in + let ty_t = NCicTypeChecker.typeof ~metasenv ~subst context t in + let metasenv,subst,t = + match kind with + `IsSort -> sortfy exc metasenv subst context t + | `IsType -> tipify exc metasenv subst context t ty_t + | `IsTerm -> metasenv,subst,t in + match kind with + | `IsSort -> + (match ty,t with + NCic.Implicit (`Typeof _), NCic.Sort _ -> + move_to_subst n (attrs,cc,t,ty_t) metasenv subst + | NCic.Sort (NCic.Type u1), NCic.Sort s -> + let s = + match s,swap with + NCic.Type u2, false -> + NCic.Sort (NCic.Type + (unopt exc (NCicEnvironment.inf ~strict:false + (unopt exc (NCicEnvironment.inf ~strict:true u1) @ u2)))) + | NCic.Type u2, true -> + if NCicEnvironment.universe_lt u2 u1 then + NCic.Sort (NCic.Type u2) + else (raise exc) + | NCic.Prop,_ -> NCic.Sort NCic.Prop + in + move_to_subst n (attrs,cc,s,ty) metasenv subst + | NCic.Implicit (`Typeof _), NCic.Meta _ -> + move_to_subst n (attrs,cc,t,ty_t) metasenv subst + | _, NCic.Meta _ + | NCic.Meta _, NCic.Sort _ -> + pp (lazy ("On the types: " ^ + ppterm ~metasenv ~subst ~context ty ^ "=<=" ^ + ppterm ~metasenv ~subst ~context ty_t)); + let metasenv, subst = + unify rdb false metasenv subst context ty_t ty false in + delift_to_subst test_eq_only n lc (attrs,cc,ty) t + context metasenv subst + | _ -> assert false) + | `IsType + | `IsTerm -> + (match ty with + NCic.Implicit (`Typeof _) -> + let (metasenv, subst), ty_t = + try + NCicMetaSubst.delift + ~unify:(fun m s c t1 t2 -> + let ind = !indent in + let res = try Some (unify rdb test_eq_only m s c t1 t2 false ) + with UnificationFailure _ | Uncertain _ -> None + in + indent := ind; res) + metasenv subst context n lc ty_t + with NCicMetaSubst.Uncertain msg -> + pp (lazy ("delift is uncertain: " ^ Lazy.force msg)); + raise (Uncertain msg) + | NCicMetaSubst.MetaSubstFailure msg -> + pp (lazy ("delift fails: " ^ Lazy.force msg)); + raise (UnificationFailure msg) + in + delift_to_subst test_eq_only n lc (attrs,cc,ty_t) t context metasenv + subst + | _ -> + let lty = NCicSubstitution.subst_meta lc ty in + pp (lazy ("On the types: " ^ + ppterm ~metasenv ~subst ~context ty_t ^ "=<=" ^ + ppterm ~metasenv ~subst ~context lty)); + let metasenv, subst = + unify rdb false metasenv subst context ty_t lty false + in + delift_to_subst test_eq_only n lc (attrs,cc,ty) t context metasenv + subst) + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn -and unify rdb test_eq_only metasenv subst context t1 t2 = +and unify rdb test_eq_only metasenv subst context t1 t2 swap = (*D*) inside 'U'; try let rc = let fo_unif test_eq_only metasenv subst (norm1,t1) (norm2,t2) = (*D*) inside 'F'; try let rc = - pp (lazy(" " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " ==?== " ^ - NCicPp.ppterm ~metasenv ~subst ~context t2 ^ ppmetasenv + pp (lazy(" " ^ ppterm ~metasenv ~subst ~context t1 ^ + (if swap then " ==>?== " + else " ==??== " + else " == prerr_endline "Appl [Appl _;_] or Appl [] or Appl [_] invariant"; assert false - | (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only -> + | (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only -> + let a, b = if swap then b,a else a,b in if NCicEnvironment.universe_leq a b then metasenv, subst else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) | (C.Sort (C.Type a), C.Sort (C.Type b)) -> if NCicEnvironment.universe_eq a b then metasenv, subst else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) - | (C.Sort C.Prop,C.Sort (C.Type _)) -> + | (C.Sort C.Prop,C.Sort (C.Type _)) when not swap -> + if (not test_eq_only) then metasenv, subst + else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) + | (C.Sort (C.Type _), C.Sort C.Prop) when swap -> if (not test_eq_only) then metasenv, subst else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) | (C.Lambda (name1,s1,t1), C.Lambda(_,s2,t2)) | (C.Prod (name1,s1,t1), C.Prod(_,s2,t2)) -> - let metasenv, subst = unify rdb true metasenv subst context s1 s2 in - unify rdb test_eq_only metasenv subst ((name1, C.Decl s1)::context) t1 t2 + let metasenv, subst = unify rdb true metasenv subst context s1 s2 swap in + unify rdb test_eq_only metasenv subst ((name1, C.Decl s1)::context) t1 t2 swap | (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) -> - let metasenv,subst=unify rdb test_eq_only metasenv subst context ty1 ty2 in - let metasenv,subst=unify rdb test_eq_only metasenv subst context s1 s2 in + let metasenv,subst=unify rdb test_eq_only metasenv subst context ty1 ty2 swap in + let metasenv,subst=unify rdb test_eq_only metasenv subst context s1 s2 swap in let context = (name1, C.Def (s1,ty1))::context in - unify rdb test_eq_only metasenv subst context t1 t2 + unify rdb test_eq_only metasenv subst context t1 t2 swap | (C.Meta (n1,(s1,l1 as lc1)),C.Meta (n2,(s2,l2 as lc2))) when n1 = n2 -> (try @@ -410,8 +456,9 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = (fun t1 t2 (metasenv, subst, to_restrict, i) -> try let metasenv, subst = - unify rdb test_eq_only metasenv subst context + unify rdb (*test_eq_only*) true metasenv subst context (NCicSubstitution.lift s1 t1) (NCicSubstitution.lift s2 t2) + swap in metasenv, subst, to_restrict, i-1 with UnificationFailure _ | Uncertain _ -> @@ -419,7 +466,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = l1 l2 (metasenv, subst, [], List.length l1) in if to_restrict <> [] then - let metasenv, subst, _ = + let metasenv, subst, _, _ = NCicMetaSubst.restrict metasenv subst n1 to_restrict in metasenv, subst @@ -431,7 +478,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let _,_,term,_ = NCicUtils.lookup_subst n1 subst in let term1 = NCicSubstitution.subst_meta lc1 term in let term2 = NCicSubstitution.subst_meta lc2 term in - unify rdb test_eq_only metasenv subst context term1 term2 + unify rdb test_eq_only metasenv subst context term1 term2 swap with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg)) | NCic.Appl (NCic.Meta (i,_)::_ as l1), @@ -439,20 +486,22 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = (try List.fold_left2 (fun (metasenv, subst) t1 t2 -> - unify rdb test_eq_only metasenv subst context t1 t2) + unify rdb (*test_eq_only*) true metasenv subst context t1 + t2 swap) (metasenv,subst) l1 l2 with Invalid_argument _ -> raise (UnificationFailure (mk_msg metasenv subst context t1 t2))) - | _, NCic.Meta (n, _) when is_locked n subst -> + | _, NCic.Meta (n, _) when is_locked n subst && not swap-> (let (metasenv, subst), i = match NCicReduction.whd ~subst context t1 with - | NCic.Appl (NCic.Meta (i,l)::args) -> - let metasenv, subst, lambda_Mj = - lambda_intros rdb metasenv subst context t1 args + | NCic.Appl (NCic.Meta (i,l) as meta :: args) -> + let metasenv, lambda_Mj = + lambda_intros rdb metasenv subst context (List.length args) + (NCicTypeChecker.typeof ~metasenv ~subst context meta) in unify rdb test_eq_only metasenv subst context - (C.Meta (i,l)) lambda_Mj, + (C.Meta (i,l)) lambda_Mj false, i | NCic.Meta (i,_) -> (metasenv, subst), i | _ -> @@ -483,94 +532,114 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let subst = List.filter (fun (j,_) -> j <> i) subst in metasenv, ((i, (name, ctx, term, ty)) :: subst) with Not_found -> assert false)) - - | C.Meta (n,lc), t when List.mem_assoc n subst -> - let _,_,term,_ = NCicUtils.lookup_subst n subst in - let term = NCicSubstitution.subst_meta lc term in - unify rdb test_eq_only metasenv subst context term t + | NCic.Meta (n, _), _ when is_locked n subst && swap -> + unify rdb test_eq_only metasenv subst context t2 t1 false | t, C.Meta (n,lc) when List.mem_assoc n subst -> let _,_,term,_ = NCicUtils.lookup_subst n subst in let term = NCicSubstitution.subst_meta lc term in - unify rdb test_eq_only metasenv subst context t term - - | NCic.Appl (NCic.Meta (i,l)::args), _ when List.mem_assoc i subst -> - let _,_,term,_ = NCicUtils.lookup_subst i subst in - let term = NCicSubstitution.subst_meta l term in - unify rdb test_eq_only metasenv subst context - (mk_appl ~upto:(List.length args) term args) t2 + unify rdb test_eq_only metasenv subst context t term swap + | C.Meta (n,_), _ when List.mem_assoc n subst -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) | _, NCic.Appl (NCic.Meta (i,l)::args) when List.mem_assoc i subst -> let _,_,term,_ = NCicUtils.lookup_subst i subst in let term = NCicSubstitution.subst_meta l term in unify rdb test_eq_only metasenv subst context t1 - (mk_appl ~upto:(List.length args) term args) - + (mk_appl ~upto:(List.length args) term args) swap + | NCic.Appl (NCic.Meta (i,_)::_), _ when List.mem_assoc i subst -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) + + | C.Meta (n,_), C.Meta (m,lc') when + let _,cc1,_ = NCicUtils.lookup_meta n metasenv in + let _,cc2,_ = NCicUtils.lookup_meta m metasenv in + (n < m && cc1 = cc2) || + let len1 = List.length cc1 in + let len2 = List.length cc2 in + len2 < len1 && cc2 = fst (HExtlib.split_nth len2 cc1) -> + instantiate rdb test_eq_only metasenv subst context m lc' + (NCicReduction.head_beta_reduce ~subst t1) (not swap) + | C.Meta (n,lc), C.Meta (m,lc') when + let _,_,tyn = NCicUtils.lookup_meta n metasenv in + let _,_,tym = NCicUtils.lookup_meta m metasenv in + let tyn = NCicSubstitution.subst_meta lc tyn in + let tym = NCicSubstitution.subst_meta lc tym in + match tyn,tym with + NCic.Sort NCic.Type u1, NCic.Sort NCic.Type u2 -> + NCicEnvironment.universe_lt u1 u2 + | _,_ -> false -> + instantiate rdb test_eq_only metasenv subst context m lc' + (NCicReduction.head_beta_reduce ~subst t1) (not swap) | C.Meta (n,lc), t -> instantiate rdb test_eq_only metasenv subst context n lc - (NCicReduction.head_beta_reduce ~subst t) false - + (NCicReduction.head_beta_reduce ~subst t) swap | t, C.Meta (n,lc) -> instantiate rdb test_eq_only metasenv subst context n lc - (NCicReduction.head_beta_reduce ~subst t) true - - | NCic.Appl (NCic.Meta (i,l)::args), _ -> - let metasenv, subst, lambda_Mj = - lambda_intros rdb metasenv subst context t1 args - in - let metasenv, subst = - try - unify rdb test_eq_only metasenv subst context - (C.Meta (i,l)) lambda_Mj - with UnificationFailure msg | Uncertain msg -> - (* failure: let's try again argument vs argument *) - raise (KeepReducing msg) - in - let metasenv, subst = - unify rdb test_eq_only metasenv subst context t1 t2 - in - (try - let name, ctx, term, ty = NCicUtils.lookup_subst i subst in - let term = eta_reduce subst term in - let subst = List.filter (fun (j,_) -> j <> i) subst in - metasenv, ((i, (name, ctx, term, ty)) :: subst) - with Not_found -> assert false) - - | _, NCic.Appl (NCic.Meta (i,l)::args) -> - let metasenv, subst, lambda_Mj = - lambda_intros rdb metasenv subst context t2 args - in - let metasenv, subst = - try - unify rdb test_eq_only metasenv subst context - lambda_Mj (C.Meta (i,l)) - with UnificationFailure msg | Uncertain msg -> - (* failure: let's try again argument vs argument *) - raise (KeepReducing msg) - in - let metasenv, subst = - unify rdb test_eq_only metasenv subst context t1 t2 - in - (try - let name, ctx, term, ty = NCicUtils.lookup_subst i subst in - let term = eta_reduce subst term in - let subst = List.filter (fun (j,_) -> j <> i) subst in - metasenv, ((i, (name, ctx, term, ty)) :: subst) - with Not_found -> assert false) + (NCicReduction.head_beta_reduce ~subst t) (not swap) + + (* higher order unification case *) + | NCic.Appl (NCic.Meta (i,l) as meta :: args), _ -> + (* this easy_case handles "(? ?) =?= (f a)", same number of + * args, preferring the instantiation "f" over "\_.f a" for the + * metavariable in head position. Since the arguments of the meta + * are flexible, delift would ignore them generating a constant + * function even in the easy case above *) + let easy_case = + match t2 with + | NCic.Appl (f :: f_args) + when + List.exists (NCicMetaSubst.is_flexible context ~subst) args -> + let mlen = List.length args in + let flen = List.length f_args in + let min_len = min mlen flen in + let mhe,margs = HExtlib.split_nth (mlen - min_len) args in + let fhe,fargs = HExtlib.split_nth (flen - min_len) f_args in + (try + Some (List.fold_left2 + (fun (m, s) t1 t2 -> + unify rdb test_eq_only m s context t1 t2 swap + ) (metasenv,subst) + ((NCicUntrusted.mk_appl meta mhe)::margs) + ((NCicUntrusted.mk_appl f fhe)::fargs)) + with UnificationFailure _ | Uncertain _ | KeepReducing _ -> + None) + | _ -> None + in + (match easy_case with + | Some ms -> ms + | None -> + (* This case handles "(?_f ..ti..) =?= t2", abstracting every + * non flexible ti (delift skips local context items that are + * flexible) from t2 in two steps: + * 1) ?_f := \..xi.. .? + * 2) ?_f ..ti.. =?= t2 --unif_machines--> + ?_f[..ti..] =?= t2 --instantiate--> + delift [..ti..] t2 *) + let metasenv, lambda_Mj = + lambda_intros rdb metasenv subst context (List.length args) + (NCicTypeChecker.typeof ~metasenv ~subst context meta) + in + let metasenv, subst = + unify rdb test_eq_only metasenv subst context + (C.Meta (i,l)) lambda_Mj swap + in + let metasenv, subst = + unify rdb test_eq_only metasenv subst context t1 t2 swap + in + (try + let name, ctx, term, ty = NCicUtils.lookup_subst i subst in + let term = eta_reduce subst term in + let subst = List.filter (fun (j,_) -> j <> i) subst in + metasenv, ((i, (name, ctx, term, ty)) :: subst) + with Not_found -> assert false)) + + | _, NCic.Appl (NCic.Meta (_,_) :: _) -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) (* processing this case here we avoid a useless small delta step *) | (C.Appl ((C.Const r1) as _hd1::tl1), C.Appl (C.Const r2::tl2)) when Ref.eq r1 r2 -> let relevance = NCicEnvironment.get_relevance r1 in - let relevance = match r1 with - | Ref.Ref (_,Ref.Con (_,_,lno)) -> - let relevance = - try snd (HExtlib.split_nth lno relevance) - with Failure _ -> [] - in - HExtlib.mk_list false lno @ relevance - | _ -> relevance - in let metasenv, subst, _ = try List.fold_left2 @@ -579,6 +648,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = match relevance with b::tl -> b,tl | _ -> true, [] in let metasenv, subst = try unify rdb test_eq_only metasenv subst context t1 t2 + swap with UnificationFailure _ | Uncertain _ when not b -> metasenv, subst in @@ -587,13 +657,12 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = with Invalid_argument _ -> raise (Uncertain (mk_msg metasenv subst context t1 t2)) - | UnificationFailure _ | Uncertain _ when not (norm1 && norm2) -> - raise (KeepReducing (mk_msg metasenv subst context t1 t2)) + | KeepReducing _ | KeepReducingThis _ -> assert false in metasenv, subst | (C.Match (Ref.Ref (_,Ref.Ind (_,tyno,_)) as ref1,outtype1,term1,pl1), - C.Match (ref2,outtype2,term2,pl2)) -> + C.Match (ref2,outtype2,term2,pl2)) when Ref.eq ref1 ref2 -> let _,_,itl,_,_ = NCicEnvironment.get_checked_indtys ref1 in let _,_,ty,_ = List.nth itl tyno in let rec remove_prods ~subst context ty = @@ -609,20 +678,20 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = | C.Sort C.Prop -> true | _ -> false in - if not (Ref.eq ref1 ref2) then + (* if not (Ref.eq ref1 ref2) then raise (Uncertain (mk_msg metasenv subst context t1 t2)) - else + else*) let metasenv, subst = - unify rdb test_eq_only metasenv subst context outtype1 outtype2 in + unify rdb test_eq_only metasenv subst context outtype1 outtype2 swap in let metasenv, subst = - try unify rdb test_eq_only metasenv subst context term1 term2 + try unify rdb test_eq_only metasenv subst context term1 term2 swap with UnificationFailure _ | Uncertain _ when is_prop -> metasenv, subst in (try List.fold_left2 - (fun (metasenv,subst) -> - unify rdb test_eq_only metasenv subst context) + (fun (metasenv,subst) t1 t2 -> + unify rdb test_eq_only metasenv subst context t1 t2 swap) (metasenv, subst) pl1 pl2 with Invalid_argument _ -> assert false) | (C.Implicit _, _) | (_, C.Implicit _) -> assert false @@ -632,13 +701,23 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) | _ -> raise (KeepReducing (mk_msg metasenv subst context t1 t2)) - (*D*) in outside true; rc with exn -> outside false; raise exn + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn + in + let fo_unif test_eq_only metasenv subst (norm1,t1 as nt1) (norm2,t2 as nt2)= + try fo_unif test_eq_only metasenv subst nt1 nt2 + with + UnificationFailure _ | Uncertain _ when not norm1 || not norm2 -> + raise (KeepReducing (mk_msg metasenv subst context t1 t2)) in let try_hints metasenv subst (_,t1 as mt1) (_,t2 as mt2) (* exc*) = + if NCicUntrusted.metas_of_term subst context t1 = [] && + NCicUntrusted.metas_of_term subst context t2 = [] + then None + else begin (*D*) inside 'H'; try let rc = pp(lazy ("\nProblema:\n" ^ - NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " =?= " ^ - NCicPp.ppterm ~metasenv ~subst ~context t2)); + ppterm ~metasenv ~subst ~context t1 ^ " =?= " ^ + ppterm ~metasenv ~subst ~context t2)); let candidates = NCicUnifHint.look_for_hint rdb metasenv subst context t1 t2 in @@ -649,11 +728,11 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = String.concat "\n" (List.map (fun (a,b) -> - NCicPp.ppterm ~metasenv ~subst ~context a ^ " =?= " ^ - NCicPp.ppterm ~metasenv ~subst ~context b) premises) ^ + ppterm ~metasenv ~subst ~context a ^ " =?= " ^ + ppterm ~metasenv ~subst ~context b) premises) ^ "\n-------------------------------------------\n"^ - NCicPp.ppterm ~metasenv ~subst ~context c1 ^ " = " ^ - NCicPp.ppterm ~metasenv ~subst ~context c2)); + ppterm ~metasenv ~subst ~context c1 ^ " = " ^ + ppterm ~metasenv ~subst ~context c2)); try (*D*) inside 'K'; try let rc = let metasenv,subst = @@ -663,17 +742,19 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let metasenv,subst = List.fold_left (fun (metasenv, subst) (x,y) -> - unify rdb test_eq_only metasenv subst context x y) - (metasenv, subst) premises + unify rdb test_eq_only metasenv subst context x y false) + (metasenv, subst) (List.rev premises) in pp(lazy("FUNZIONA!")); Some (metasenv, subst) - (*D*) in outside true; rc with exn -> outside false; raise exn + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn with KeepReducing _ | UnificationFailure _ | Uncertain _ -> cand_iter tl + | KeepReducingThis _ -> assert false in cand_iter candidates - (*D*) in outside true; rc with exn -> outside false; raise exn + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn + end in let put_in_whd m1 m2 = NCicReduction.reduce_machine ~delta:max_int ~subst context m1, @@ -698,6 +779,32 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = | Uncertain _ as exn -> raise exn | _ -> assert false in + let fo_unif_heads_and_cont_or_unwind_and_hints + test_eq_only metasenv subst m1 m2 cont hm1 hm2 + = + let ms, continuation = + (* calling the continuation inside the outermost try is an option + and makes unification stronger, but looks not frequent to me + that heads unify but not the arguments and that an hints can fix + that *) + try fo_unif test_eq_only metasenv subst m1 m2, cont + with + | UnificationFailure _ + | KeepReducing _ | Uncertain _ as exn -> + let (t1,norm1),(t2,norm2) = hm1, hm2 in + match + try_hints metasenv subst + (norm1,NCicReduction.unwind t1) (norm2,NCicReduction.unwind t2) + with + | Some x -> x, fun x -> x + | None -> + match exn with + | KeepReducing msg -> raise (KeepReducingThis (msg,hm1,hm2)) + | UnificationFailure _ | Uncertain _ as exn -> raise exn + | _ -> assert false + in + continuation ms + in let height_of = function | NCic.Const (Ref.Ref (_,Ref.Def h)) | NCic.Const (Ref.Ref (_,Ref.Fix (_,_,h))) @@ -725,17 +832,17 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = | ((k1,e1,t1,s1),norm1 as m1),((k2,e2,t2,s2),norm2 as m2) -> (*D*) inside 'M'; try let rc = pp (lazy("UM: " ^ - NCicPp.ppterm ~metasenv ~subst ~context + ppterm ~metasenv ~subst ~context (NCicReduction.unwind (k1,e1,t1,s1)) ^ " === " ^ - NCicPp.ppterm ~metasenv ~subst ~context + ppterm ~metasenv ~subst ~context (NCicReduction.unwind (k2,e2,t2,s2)))); pp (lazy (string_of_bool norm1 ^ " ?? " ^ string_of_bool norm2)); let relevance = [] (* TO BE UNDERSTOOD match t1 with | C.Const r -> NCicEnvironment.get_relevance r | _ -> [] *) in - let unif_from_stack t1 t2 b metasenv subst = + let unif_from_stack (metasenv, subst) (t1, t2, b) = try let t1 = NCicReduction.from_stack ~delta:max_int t1 in let t2 = NCicReduction.from_stack ~delta:max_int t2 in @@ -752,26 +859,31 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = NCicReduction.unwind (k2,e2,t2,List.rev l2), todo in - let hh1,hh2,todo=check_stack (List.rev s1) (List.rev s2) relevance [] in + let check_stack l1 l2 r = + match t1, t2 with + | NCic.Meta _, _ | _, NCic.Meta _ -> + (NCicReduction.unwind (k1,e1,t1,s1)), + (NCicReduction.unwind (k2,e2,t2,s2)),[] + | _ -> check_stack l1 l2 r [] + in + let hh1,hh2,todo = check_stack (List.rev s1) (List.rev s2) relevance in try - let metasenv,subst = - fo_unif_w_hints test_eq_only metasenv subst (norm1,hh1) (norm2,hh2) in - List.fold_left - (fun (metasenv,subst) (x1,x2,r) -> - unif_from_stack x1 x2 r metasenv subst - ) (metasenv,subst) todo + fo_unif_heads_and_cont_or_unwind_and_hints + test_eq_only metasenv subst (norm1,hh1) (norm2,hh2) + (fun ms -> List.fold_left unif_from_stack ms todo) + m1 m2 with | KeepReducing _ -> assert false | KeepReducingThis _ -> assert (not (norm1 && norm2)); - unif_machines metasenv subst (small_delta_step ~subst m1 m2) + unif_machines metasenv subst (small_delta_step ~subst m1 m2) | UnificationFailure _ | Uncertain _ when (not (norm1 && norm2)) -> unif_machines metasenv subst (small_delta_step ~subst m1 m2) | UnificationFailure msg when could_reduce (NCicReduction.unwind (fst m1)) || could_reduce (NCicReduction.unwind (fst m2)) -> raise (Uncertain msg) - (*D*) in outside true; rc with exn -> outside false; raise exn + (*D*) in outside None; rc with exn -> outside (Some exn); raise exn in try fo_unif_w_hints test_eq_only metasenv subst (false,t1) (false,t2) with @@ -784,7 +896,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = | KeepReducing _ -> assert false) | KeepReducing _ -> assert false - (*D*) in outside true; rc with KeepReducing _ -> assert false | exn -> outside false; raise exn + (*D*) in outside None; rc with KeepReducing _ -> assert false | exn -> outside (Some exn); raise exn and delift_type_wrt_terms rdb metasenv subst context t args = let lc = List.rev args @ mk_irl (List.length context) (List.length args+1) in @@ -794,7 +906,7 @@ and delift_type_wrt_terms rdb metasenv subst context t args = ~unify:(fun m s c t1 t2 -> let ind = !indent in let res = - try Some (unify rdb false m s c t1 t2 ) + try Some (unify rdb false m s c t1 t2 false) with UnificationFailure _ | Uncertain _ -> None in indent := ind; res) @@ -807,8 +919,10 @@ and delift_type_wrt_terms rdb metasenv subst context t args = ;; -let unify rdb ?(test_eq_only=false) = +let unify rdb ?(test_eq_only=false) ?(swap=false) metasenv subst context t1 t2= indent := ""; - unify rdb test_eq_only;; + unify rdb test_eq_only metasenv subst context t1 t2 swap;; -let fix_sorts = fix_sorts true (UnificationFailure (lazy "no sup"));; +let fix_sorts m s = + fix m s true false (UnificationFailure (lazy "no sup")) +;;