exception UnificationFailure of string Lazy.t;;
exception Uncertain of string Lazy.t;;
exception AssertFailure of string Lazy.t;;
+exception KeepReducing of string Lazy.t;;
+exception KeepReducingThis of
+ string Lazy.t * (NCicReduction.machine * bool) *
+ (NCicReduction.machine * bool) ;;
let (===) x y = Pervasives.compare x y = 0 ;;
-let uncert_exc metasenv subst context t1 t2 =
- Uncertain (lazy (
+let mk_msg metasenv subst context t1 t2 =
+ (lazy (
"Can't unify " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^
" with " ^ NCicPp.ppterm ~metasenv ~subst ~context t2))
-;;
-
-let fail_exc metasenv subst context t1 t2 =
- UnificationFailure (lazy (
- "Can't unify " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^
- " with " ^ NCicPp.ppterm ~metasenv ~subst ~context t2));
-;;
-
-let mk_appl hd tl =
- match hd with
- | NCic.Appl l -> NCic.Appl (l@tl)
- | _ -> NCic.Appl (hd :: tl)
-;;
-let flexible l =
- List.exists
- (function
- | NCic.Meta _
- | NCic.Appl (NCic.Meta _::_) -> true
- | _ -> false) l
+let mk_appl ~upto hd tl =
+ NCicReduction.head_beta_reduce ~upto
+ (match hd with
+ | NCic.Appl l -> NCic.Appl (l@tl)
+ | _ -> NCic.Appl (hd :: tl))
;;
exception WrongShape;;
-let eta_reduce =
- let delift_if_not_occur body orig =
+let eta_reduce subst t =
+ let delift_if_not_occur body =
try
- NCicSubstitution.psubst ~avoid_beta_redexes:true
- (fun () -> raise WrongShape) [()] body
- with WrongShape -> orig
+ Some (NCicSubstitution.psubst ~avoid_beta_redexes:true
+ (fun () -> raise WrongShape) [()] body)
+ with WrongShape -> None
+ in
+ let rec eat_lambdas ctx = function
+ | NCic.Lambda (name, src, tgt) ->
+ eat_lambdas ((name, src) :: ctx) tgt
+ | NCic.Meta (i,lc) as t->
+ (try
+ 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)
+ | t -> ctx, t
in
- function
- | NCic.Lambda(_, _, NCic.Appl [hd; NCic.Rel 1]) as orig ->
- delift_if_not_occur hd orig
- | NCic.Lambda(_, _, NCic.Appl (hd :: l)) as orig
- when HExtlib.list_last l = NCic.Rel 1 ->
- let body =
- let args, _ = HExtlib.split_nth (List.length l - 1) l in
- NCic.Appl (hd::args)
- in
- delift_if_not_occur body orig
- | t -> t
+ let context_body = eat_lambdas [] t in
+ let rec aux = function
+ | [],body -> body
+ | (name, src)::ctx, (NCic.Appl (hd::[NCic.Rel 1]) as bo) ->
+ (match delift_if_not_occur hd with
+ | None -> aux (ctx,NCic.Lambda(name,src, bo))
+ | Some bo -> aux (ctx,bo))
+ | (name, src)::ctx, (NCic.Appl args as bo)
+ when HExtlib.list_last args = NCic.Rel 1 ->
+ let args, _ = HExtlib.split_nth (List.length args - 1) args in
+ (match delift_if_not_occur (NCic.Appl args) with
+ | None -> aux (ctx,NCic.Lambda(name,src, bo))
+ | Some bo -> aux (ctx,bo))
+ | (name, src) :: ctx, t ->
+ aux (ctx,NCic.Lambda(name,src, t))
+ in
+ aux context_body
;;
-
+
module C = NCic;;
module Ref = NReference;;
+let debug = ref false;;
let indent = ref "";;
-let inside c = indent := !indent ^ String.make 1 c;;
-let outside () = indent := String.sub !indent 0 (String.length !indent -1);;
-
-(*
-let pp s =
+let times = ref [];;
+let pp s =
+ if !debug then
prerr_endline (Printf.sprintf "%-20s" !indent ^ " " ^ Lazy.force s)
-;;
-*)
+;;
+let inside c =
+ if !debug then
+ begin
+ let time1 = Unix.gettimeofday () in
+ indent := !indent ^ String.make 1 c;
+ times := time1 :: !times;
+ prerr_endline ("{{{" ^ !indent ^ " ")
+ end
+;;
+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));
+ (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
+ Invalid_argument _ -> indent := "??"; ()
+ end
+;;
-let pp _ = ();;
+let ppcontext ~metasenv ~subst c =
+ "\nctx:\n"^ NCicPp.ppcontext ~metasenv ~subst c
+;;
+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 metasenv subst context meta t =
+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" ;
- raise (fail_exc metasenv subst context meta t)
+ | 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 (
aux () t
;;
-let rec beta_expand hdb num test_eq_only swap metasenv subst context t arg =
- let rec aux (n,context,test_eq_only as k) (metasenv, subst as acc) t' =
+let is_locked n subst =
try
- let metasenv, subst =
- if swap then
- unify hdb test_eq_only metasenv subst context t' (NCicSubstitution.lift n arg)
- else
- unify hdb test_eq_only metasenv subst context (NCicSubstitution.lift n arg) t'
- in
- (metasenv, subst), NCic.Rel (1 + n)
- with Uncertain _ | UnificationFailure _ ->
- match t' with
- | NCic.Rel m as orig ->
- (metasenv, subst), if m <= n then orig else NCic.Rel (m+1)
- (* andrea: in general, beta_expand can create badly typed
- terms. This happens quite seldom in practice, UNLESS we
- iterate on the local context. For this reason, we renounce
- to iterate and just lift *)
- | NCic.Meta (i,(shift,lc)) ->
- (metasenv,subst), NCic.Meta (i,(shift+1,lc))
- | NCic.Prod (name, src, tgt) as orig ->
- let (metasenv, subst), src1 = aux (n,context,true) acc src in
- let k = n+1, (name, NCic.Decl src) :: context, test_eq_only in
- let ms, tgt1 = aux k (metasenv, subst) tgt in
- if src == src1 && tgt == tgt1 then ms, orig else
- ms, NCic.Prod (name, src1, tgt1)
- | t ->
- NCicUntrusted.map_term_fold_a
- (fun e (n,ctx,teq) -> n+1,e::ctx,teq) k aux acc t
+ match NCicUtils.lookup_subst n subst with
+ | tag, _,_,_ when NCicMetaSubst.is_out_scope_tag tag -> true
+ | _ -> false
+ with NCicUtils.Subst_not_found _ -> false
+;;
- in
- let argty = NCicTypeChecker.typeof ~metasenv ~subst context arg in
- let fresh_name = "Hbeta" ^ string_of_int num in
- let (metasenv,subst), t1 =
- aux (0, context, test_eq_only) (metasenv, subst) t in
- let t2 = eta_reduce (NCic.Lambda (fresh_name,argty,t1)) in
- try
- ignore(NCicTypeChecker.typeof ~metasenv ~subst context t2);
- metasenv, subst, t2
- with NCicTypeChecker.TypeCheckerFailure _ ->
- metasenv, subst, NCic.Lambda ("_", argty, NCicSubstitution.lift 1 arg)
-
-and beta_expand_many hdb test_equality_only swap metasenv subst context t args =
-(* (*D*) inside 'B'; try let rc = *)
- pp (lazy (String.concat ", "
- (List.map (NCicPp.ppterm ~metasenv ~subst ~context)
- args) ^ " ∈ " ^ NCicPp.ppterm ~metasenv ~subst ~context t));
- let _, subst, metasenv, hd =
- List.fold_right
- (fun arg (num,subst,metasenv,t) ->
- let metasenv, subst, t =
- beta_expand hdb num test_equality_only swap metasenv subst context t arg
- in
- num+1,subst,metasenv,t)
- args (1,subst,metasenv,t)
- in
- pp (lazy ("Head syntesized by b-exp: " ^
- NCicPp.ppterm ~metasenv ~subst ~context hd));
- metasenv, subst, hd
-(* (*D*) in outside (); rc with exn -> outside (); raise exn *)
+let rec mk_irl stop base =
+ if base > stop then []
+ else (NCic.Rel base) :: mk_irl stop (base+1)
+;;
-and instantiate hdb test_eq_only metasenv subst context n lc t swap =
+(* the argument must be a term in whd *)
+let rec could_reduce =
+ function
+ | C.Meta _ -> true
+ | C.Appl (C.Const (Ref.Ref (_,Ref.Fix (_,recno,_)))::args)
+ when List.length args > recno -> could_reduce (List.nth args recno)
+ | C.Match (_,_,arg,_) -> could_reduce arg
+ | C.Appl (he::_) -> could_reduce he
+ | C.Sort _ | C.Rel _ | C.Prod _ | C.Lambda _ | C.Const _ -> false
+ | C.Appl [] | C.LetIn _ | C.Implicit _ -> assert false
+;;
+
+let rec lambda_intros rdb metasenv subst context argsno ty =
+ pp (lazy ("LAMBDA INTROS: " ^ NCicPp.ppterm ~metasenv ~subst ~context ty));
+ match argsno with
+ 0 ->
+ let metasenv, _, bo, _ =
+ NCicMetaSubst.mk_meta metasenv context (`WithType ty)
+ in
+ 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,C.Lambda (n,so,bo)
+ | _ -> assert false)
+;;
+
+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 ^ " :=?= "^
NCicPp.ppterm ~metasenv ~subst ~context t));
let unify test_eq_only m s c t1 t2 =
- if swap then unify hdb test_eq_only m s c t2 t1
- else unify hdb 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 name, ctx, ty = NCicUtils.lookup_meta n metasenv 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 _) ->
- metasenv,subst, t
- (* fix_sorts swap metasenv subst context (NCic.Meta(n,lc)) t *)
+ pp(lazy("meta with no type"));
+ assert(has_tag ((=)`IsSort) tags);
+ metasenv, subst, t
| _ ->
- pp (lazy (
- "typeof: " ^ NCicPp.ppterm ~metasenv ~subst ~context t ^ "\nctx:\n"^
- NCicPp.ppcontext ~metasenv ~subst context ^ "\nmenv:\n"^
- NCicPp.ppmetasenv ~subst metasenv));
+ let exc_to_be =
+ UnificationFailure (mk_msg metasenv subst context (NCic.Meta (n,lc)) t)
+ in
let t, ty_t =
try t, NCicTypeChecker.typeof ~subst ~metasenv context t
with
- | NCicTypeChecker.AssertFailure msg ->
- (pp (lazy "fine typeof (fallimento)");
- let ft=fix_sorts swap metasenv subst context (NCic.Meta (n,lc)) t in
- if ft == t then
- (prerr_endline ( ("ILLTYPED: " ^
- NCicPp.ppterm ~metasenv ~subst ~context t
- ^ "\nBECAUSE:" ^ Lazy.force msg ^ "\nCONTEXT:\n" ^
- NCicPp.ppcontext ~metasenv ~subst context ^ "\nMENV:\n" ^
- NCicPp.ppmetasenv ~subst metasenv
- ));
- assert false)
- else
- try
- pp (lazy ("typeof: " ^
- NCicPp.ppterm ~metasenv ~subst ~context ft));
- ft, NCicTypeChecker.typeof ~subst ~metasenv context ft
- with NCicTypeChecker.AssertFailure _ ->
- assert false)
+ | 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);
- pp msg; assert false
+ prerr_endline (NCicPp.ppterm ~metasenv ~subst ~context t);
+ prerr_endline (ppcontext ~metasenv ~subst context);
+ prerr_endline (ppmetasenv ~subst metasenv);
+ assert false
in
- let lty = NCicSubstitution.subst_meta lc ty in
- pp (lazy ("On the types: " ^
- NCicPp.ppterm ~metasenv ~subst ~context:ctx ty ^ " ~~~ " ^
- NCicPp.ppterm ~metasenv ~subst ~context lty ^ " === "
- ^ NCicPp.ppterm ~metasenv ~subst ~context ty_t));
- let metasenv,subst= unify test_eq_only metasenv subst context lty ty_t in
- metasenv, subst, t
+ 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
+ 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
- pp (lazy(string_of_int n ^ " := 111 = "^
- NCicPp.ppterm ~metasenv ~subst ~context t));
+ 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, lambda_Mj =
+ lambda_intros rdb metasenv subst context (List.length args)
+ (NCicTypeChecker.typeof ~metasenv ~subst context hd)
+ 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
+ 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 metasenv subst context n lc 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
+ in
+ indent := ind; res)
+ metasenv subst context n lc t
with NCicMetaSubst.Uncertain msg ->
pp (lazy ("delift fails: " ^ Lazy.force msg));
raise (Uncertain msg)
in
pp (lazy(string_of_int n ^ " := 222 = "^
NCicPp.ppterm ~metasenv ~subst ~context:ctx t
- ^ "\n" ^ NCicPp.ppmetasenv ~subst metasenv));
+ ^ ppmetasenv ~subst metasenv));
(* Unifying the types may have already instantiated n. *)
try
let _, _,oldt,_ = NCicUtils.lookup_subst n subst 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, (name, ctx, t, ty)) :: subst in
+ 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
in
metasenv, subst
- (*D*) in outside(); rc with exn -> outside (); raise exn
+ (*D*) in outside None; rc with exn -> outside (Some exn); raise exn
-and unify hdb test_eq_only metasenv subst context t1 t2 =
+and unify rdb test_eq_only metasenv subst context t1 t2 =
(*D*) inside 'U'; try let rc =
- let fo_unif test_eq_only metasenv subst t1 t2 =
+ 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 ^ "\n" ^ NCicPp.ppmetasenv
+ NCicPp.ppterm ~metasenv ~subst ~context t2 ^ ppmetasenv
+ ~subst metasenv));
+ pp (lazy(" " ^ NCicPp.ppterm ~metasenv ~subst:[] ~context t1 ^ " ==??== " ^
+ NCicPp.ppterm ~metasenv ~subst:[] ~context t2 ^ ppmetasenv
~subst metasenv));
if t1 === t2 then
metasenv, subst
assert false
| (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only ->
if NCicEnvironment.universe_leq a b then metasenv, subst
- else raise (fail_exc metasenv subst context t1 t2)
+ 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 (fail_exc metasenv subst context t1 t2)
+ else raise (UnificationFailure (mk_msg metasenv subst context t1 t2))
| (C.Sort C.Prop,C.Sort (C.Type _)) ->
if (not test_eq_only) then metasenv, subst
- else raise (fail_exc metasenv subst context t1 t2)
+ 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 hdb true metasenv subst context s1 s2 in
- unify hdb test_eq_only metasenv subst ((name1, C.Decl s1)::context) t1 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
| (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) ->
- let metasenv,subst=unify hdb test_eq_only metasenv subst context ty1 ty2 in
- let metasenv,subst=unify hdb test_eq_only metasenv subst context s1 s2 in
+ 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 context = (name1, C.Def (s1,ty1))::context in
- unify hdb test_eq_only metasenv subst context t1 t2
+ unify rdb test_eq_only metasenv subst context t1 t2
| (C.Meta (n1,(s1,l1 as lc1)),C.Meta (n2,(s2,l2 as lc2))) when n1 = n2 ->
(try
(fun t1 t2 (metasenv, subst, to_restrict, i) ->
try
let metasenv, subst =
- unify hdb test_eq_only metasenv subst context
+ unify rdb test_eq_only metasenv subst context
(NCicSubstitution.lift s1 t1) (NCicSubstitution.lift s2 t2)
in
metasenv, subst, to_restrict, i-1
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 hdb test_eq_only metasenv subst context term1 term2
+ unify rdb test_eq_only metasenv subst context term1 term2
with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg))
- | C.Meta (n,lc), t ->
- (try
- let _,_,term,_ = NCicUtils.lookup_subst n subst in
- let term = NCicSubstitution.subst_meta lc term in
- unify hdb test_eq_only metasenv subst context term t
- with NCicUtils.Subst_not_found _->
- instantiate hdb test_eq_only metasenv subst context n lc t false)
-
- | t, C.Meta (n,lc) ->
- (try
- let _,_,term,_ = NCicUtils.lookup_subst n subst in
- let term = NCicSubstitution.subst_meta lc term in
- unify hdb test_eq_only metasenv subst context t term
- with NCicUtils.Subst_not_found _->
- instantiate hdb test_eq_only metasenv subst context n lc t true)
-
- | 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 hdb test_eq_only metasenv subst context (mk_appl term args) t2
-
- | _, 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 hdb test_eq_only metasenv subst context t1 (mk_appl term args)
-
| NCic.Appl (NCic.Meta (i,_)::_ as l1),
NCic.Appl (NCic.Meta (j,_)::_ as l2) when i=j ->
(try
List.fold_left2
(fun (metasenv, subst) t1 t2 ->
- unify hdb test_eq_only metasenv subst context t1 t2)
+ unify rdb test_eq_only metasenv subst context t1 t2)
(metasenv,subst) l1 l2
with Invalid_argument _ ->
- raise (fail_exc metasenv subst context t1 t2))
-
- | NCic.Appl (NCic.Meta (i,l)::args), _ when not (flexible args) ->
- (* we verify that none of the args is a Meta,
- since beta expanding w.r.t a metavariable makes no sense *)
- let metasenv, subst, beta_expanded =
- beta_expand_many hdb
- test_eq_only false
- metasenv subst context t2 args
+ raise (UnificationFailure (mk_msg metasenv subst context t1 t2)))
+
+ | _, NCic.Meta (n, _) when is_locked n subst ->
+ (let (metasenv, subst), i =
+ match NCicReduction.whd ~subst context t1 with
+ | 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,
+ i
+ | NCic.Meta (i,_) -> (metasenv, subst), i
+ | _ ->
+ raise (UnificationFailure (lazy "Locked term vs non
+ flexible term; probably not saturated enough yet!"))
+ in
+ let t1 = NCicReduction.whd ~subst context t1 in
+ let j, lj =
+ match t1 with NCic.Meta (j,l) -> j, l | _ -> assert false
+ in
+ let metasenv, subst =
+ instantiate rdb test_eq_only metasenv subst context j lj t2 true
in
- unify hdb test_eq_only metasenv subst context
- (C.Meta (i,l)) beta_expanded
-
- | _, NCic.Appl (NCic.Meta (i,l)::args) when not(flexible args) ->
- let metasenv, subst, beta_expanded =
- beta_expand_many hdb
- test_eq_only true
- metasenv subst context t1 args
+ (* We need to remove the out_scope_tags to avoid propagation of
+ them that triggers again the ad-hoc case *)
+ let subst =
+ List.map (fun (i,(tag,ctx,bo,ty)) ->
+ let tag =
+ List.filter
+ (function `InScope | `OutScope _ -> false | _ -> true) tag
+ in
+ i,(tag,ctx,bo,ty)
+ ) subst
in
- unify hdb test_eq_only metasenv subst context
- beta_expanded (C.Meta (i,l))
+ (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))
+
+ | 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
+
+ | 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
+
+ | _, 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)
+
+ | C.Meta (n,lc), t ->
+ instantiate rdb test_eq_only metasenv subst context n lc
+ (NCicReduction.head_beta_reduce ~subst t) false
+
+ | 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) as meta :: args), _ ->
+ let metasenv, lambda_Mj =
+ lambda_intros rdb metasenv subst context (List.length args)
+ (NCicTypeChecker.typeof ~metasenv ~subst context meta)
+ in
+ let metasenv, subst =
+ try
+ unify rdb test_eq_only metasenv subst context
+ (C.Meta (i,l)) lambda_Mj
+ with UnificationFailure msg | Uncertain msg when not norm2->
+ (* 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) as meta :: args) ->
+ let metasenv, lambda_Mj =
+ lambda_intros rdb metasenv subst context (List.length args)
+ (NCicTypeChecker.typeof ~metasenv ~subst context meta)
+ in
+ let metasenv, subst =
+ try
+ unify rdb test_eq_only metasenv subst context
+ lambda_Mj (C.Meta (i,l))
+ with UnificationFailure msg | Uncertain msg when not norm1 ->
+ (* 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)
(* 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 = HExtlib.split_nth lno relevance in
- HExtlib.mk_list false lno @ relevance
- | _ -> relevance
- in
let metasenv, subst, _ =
try
List.fold_left2
let b, relevance =
match relevance with b::tl -> b,tl | _ -> true, [] in
let metasenv, subst =
- try unify hdb test_eq_only metasenv subst context t1 t2
+ try unify rdb test_eq_only metasenv subst context t1 t2
with UnificationFailure _ | Uncertain _ when not b ->
metasenv, subst
in
metasenv, subst, relevance)
(metasenv, subst, relevance) tl1 tl2
- with Invalid_argument _ ->
- raise (uncert_exc 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
| _ -> false
in
if not (Ref.eq ref1 ref2) then
- raise (uncert_exc metasenv subst context t1 t2)
+ raise (Uncertain (mk_msg metasenv subst context t1 t2))
else
let metasenv, subst =
- unify hdb test_eq_only metasenv subst context outtype1 outtype2 in
+ unify rdb test_eq_only metasenv subst context outtype1 outtype2 in
let metasenv, subst =
- try unify hdb test_eq_only metasenv subst context term1 term2
+ try unify rdb test_eq_only metasenv subst context term1 term2
with UnificationFailure _ | Uncertain _ when is_prop ->
metasenv, subst
in
(try
List.fold_left2
(fun (metasenv,subst) ->
- unify hdb test_eq_only metasenv subst context)
+ unify rdb test_eq_only metasenv subst context)
(metasenv, subst) pl1 pl2
- with Invalid_argument _ ->
- raise (uncert_exc metasenv subst context t1 t2))
+ with Invalid_argument _ -> assert false)
| (C.Implicit _, _) | (_, C.Implicit _) -> assert false
- | _ when NCicUntrusted.metas_of_term subst context t1 = [] &&
- NCicUntrusted.metas_of_term subst context t2 = [] ->
- raise (fail_exc metasenv subst context t1 t2)
- | _ -> raise (uncert_exc metasenv subst context t1 t2)
- (*D*) in outside(); rc with exn -> outside (); raise exn
+ | _ when norm1 && norm2 ->
+ if (could_reduce t1 || could_reduce t2) then
+ raise (Uncertain (mk_msg 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 None; rc with exn -> outside (Some exn); raise exn
in
- let try_hints metasenv subst t1 t2 (* exc*) =
+ let try_hints metasenv subst (_,t1 as mt1) (_,t2 as mt2) (* exc*) =
+ (*D*) inside 'H'; try let rc =
+ pp(lazy ("\nProblema:\n" ^
+ NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " =?= " ^
+ NCicPp.ppterm ~metasenv ~subst ~context t2));
let candidates =
- NCicUnifHint.look_for_hint hdb metasenv subst context t1 t2
+ NCicUnifHint.look_for_hint rdb metasenv subst context t1 t2
in
let rec cand_iter = function
| [] -> None (* raise exc *)
- | (metasenv,c1,c2)::tl ->
+ | (metasenv,(c1,c2),premises)::tl ->
+ pp (lazy ("\nProvo il candidato:\n" ^
+ String.concat "\n"
+ (List.map
+ (fun (a,b) ->
+ NCicPp.ppterm ~metasenv ~subst ~context a ^ " =?= " ^
+ NCicPp.ppterm ~metasenv ~subst ~context b) premises) ^
+ "\n-------------------------------------------\n"^
+ NCicPp.ppterm ~metasenv ~subst ~context c1 ^ " = " ^
+ NCicPp.ppterm ~metasenv ~subst ~context c2));
try
- let metasenv,subst = fo_unif test_eq_only metasenv subst t1 c1 in
- let metasenv,subst = fo_unif test_eq_only metasenv subst c2 t2 in
+ (*D*) inside 'K'; try let rc =
+ let metasenv,subst =
+ fo_unif test_eq_only metasenv subst mt1 (false,c1) in
+ let metasenv,subst =
+ fo_unif test_eq_only metasenv subst (false,c2) mt2 in
+ let metasenv,subst =
+ List.fold_left
+ (fun (metasenv, subst) (x,y) ->
+ unify rdb test_eq_only metasenv subst context x y)
+ (metasenv, subst) premises
+ in
+ pp(lazy("FUNZIONA!"));
Some (metasenv, subst)
+ (*D*) in outside None; rc with exn -> outside (Some exn); raise exn
with
- UnificationFailure _ | Uncertain _ -> cand_iter tl
+ KeepReducing _ | UnificationFailure _ | Uncertain _ -> cand_iter tl
+ | KeepReducingThis _ -> assert false
in
cand_iter candidates
+ (*D*) in outside None; rc with exn -> outside (Some exn); raise exn
+ in
+ let put_in_whd m1 m2 =
+ NCicReduction.reduce_machine ~delta:max_int ~subst context m1,
+ NCicReduction.reduce_machine ~delta:max_int ~subst context m2
+ in
+ let fo_unif_w_hints test_eq_only metasenv subst (xx1,t1 as m1) (xx2,t2 as m2) =
+ try fo_unif test_eq_only metasenv subst m1 m2
+ with
+ | UnificationFailure _ as exn -> raise exn
+ | KeepReducing _ | Uncertain _ as exn ->
+ let (t1,norm1 as tm1),(t2,norm2 as tm2) =
+ put_in_whd (0,[],t1,[]) (0,[],t2,[])
+ in
+ match
+ try_hints metasenv subst
+ (norm1,NCicReduction.unwind t1) (norm2,NCicReduction.unwind t2)
+ with
+ | Some x -> x
+ | None ->
+ match exn with
+ | KeepReducing msg -> raise (KeepReducingThis (msg,tm1,tm2))
+ | Uncertain _ as exn -> raise exn
+ | _ -> assert false
in
let height_of = function
| NCic.Const (Ref.Ref (_,Ref.Def h))
| NCic.Appl(NCic.Const(Ref.Ref(_,Ref.Fix (_,_,h)))::_) -> h
| _ -> 0
in
- let put_in_whd m1 m2 =
- NCicReduction.reduce_machine ~delta:max_int ~subst context m1,
- NCicReduction.reduce_machine ~delta:max_int ~subst context m2
- in
let small_delta_step ~subst
((_,_,t1,_ as m1, norm1) as x1) ((_,_,t2,_ as m2, norm2) as x2)
=
assert (not (norm1 && norm2));
if norm1 then
- x1,NCicReduction.reduce_machine ~delta:(height_of t2 -1) ~subst context m2
+ x1,NCicReduction.reduce_machine ~delta:0 ~subst context m2
else if norm2 then
- NCicReduction.reduce_machine ~delta:(height_of t1 -1) ~subst context m1,x2
+ NCicReduction.reduce_machine ~delta:0 ~subst context m1,x2
else
let h1 = height_of t1 in
let h2 = height_of t2 in
" === " ^
NCicPp.ppterm ~metasenv ~subst ~context
(NCicReduction.unwind (k2,e2,t2,s2))));
-pp (lazy (string_of_bool norm1 ^ " ?? " ^ string_of_bool norm2));
+ 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 =
try
- let t1 = NCicReduction.from_stack t1 in
- let t2 = NCicReduction.from_stack t2 in
+ let t1 = NCicReduction.from_stack ~delta:max_int t1 in
+ let t2 = NCicReduction.from_stack ~delta:max_int t2 in
unif_machines metasenv subst (put_in_whd t1 t2)
with UnificationFailure _ | Uncertain _ when not b ->
metasenv, subst
in
let hh1,hh2,todo=check_stack (List.rev s1) (List.rev s2) relevance [] in
try
- let metasenv,subst = fo_unif test_eq_only metasenv subst hh1 hh2 in
+ 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
- with UnificationFailure _ | Uncertain _ when not (norm1 && norm2) ->
+ with
+ | KeepReducing _ -> assert false
+ | KeepReducingThis _ ->
+ assert (not (norm1 && norm2));
unif_machines metasenv subst (small_delta_step ~subst m1 m2)
- (*D*) in outside(); rc with exn -> outside (); raise exn
+ | 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 None; rc with exn -> outside (Some exn); raise exn
in
- try fo_unif test_eq_only metasenv subst t1 t2
- with UnificationFailure msg | Uncertain msg as exn ->
- match try_hints metasenv subst t1 t2 with
- | Some x -> x
- | None ->
- try
- unif_machines metasenv subst
- (put_in_whd (0,[],t1,[]) (0,[],t2,[]))
+ try fo_unif_w_hints test_eq_only metasenv subst (false,t1) (false,t2)
+ with
+ | KeepReducingThis (msg,tm1,tm2) ->
+ (try
+ unif_machines metasenv subst (tm1,tm2)
with
| UnificationFailure _ -> raise (UnificationFailure msg)
- | Uncertain _ -> raise exn
- (*D*) in outside(); rc with exn -> outside (); raise exn
+ | Uncertain _ -> raise (Uncertain msg)
+ | KeepReducing _ -> assert false)
+ | KeepReducing _ -> assert false
+
+ (*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
+ let (metasenv, subst), t =
+ try
+ NCicMetaSubst.delift
+ ~unify:(fun m s c t1 t2 ->
+ let ind = !indent in
+ let res =
+ try Some (unify rdb false m s c t1 t2 )
+ with UnificationFailure _ | Uncertain _ -> None
+ in
+ indent := ind; res)
+ metasenv subst context 0 (0,NCic.Ctx lc) t
+ with
+ NCicMetaSubst.MetaSubstFailure _
+ | NCicMetaSubst.Uncertain _ -> (metasenv, subst), t
+ in
+ metasenv, subst, t
;;
-let unify hdb =
- indent := "";
- unify hdb false;;
+let unify rdb ?(test_eq_only=false) =
+ indent := "";
+ unify rdb test_eq_only;;
+let fix_sorts = fix_sorts true (UnificationFailure (lazy "no sup"));;