exception MetaSubstFailure of string Lazy.t
exception Uncertain of string Lazy.t
-let newmeta =
+let newmeta,maxmeta =
let maxmeta = ref 0 in
- fun () -> incr maxmeta; !maxmeta
+ (fun () -> incr maxmeta; !maxmeta),
+ (fun () -> !maxmeta)
;;
exception NotInTheList;;
-let position n (shift, lc) =
+let position to_skip n (shift, lc) =
match lc with
+ | NCic.Irl _ when to_skip > 0 -> assert false (* unclear to me *)
| NCic.Irl len when n <= shift || n > shift + len -> raise NotInTheList
| NCic.Irl _ -> n - shift
| NCic.Ctx tl ->
- let rec aux k = function
+ let rec aux to_skip k = function
| [] -> raise NotInTheList
+ | _ :: tl when to_skip > 0 -> aux (to_skip - 1) (k+1) tl
| (NCic.Rel m)::_ when m + shift = n -> k
- | _::tl -> aux (k+1) tl
+ | _::tl -> aux to_skip (k+1) tl
in
- aux 1 tl
+ aux to_skip 1 tl
;;
let pack_lc orig =
in
if amount > 0 then ms, NCic.Rel (r - amount) else ms, orig
| NCic.Meta (n, (shift,lc as l)) as orig ->
- (* we ignore the subst since restrict will take care of already
- * instantiated/restricted metavariabels *)
- let (metasenv,subst as ms), restrictions_for_n, l' =
- let l = NCicUtils.expand_local_context lc in
-
- let ms, _, restrictions_for_n, l =
- List.fold_right
- (fun t (ms, i, restrictions_for_n, l) ->
- try
- let ms, t = aux (k-shift) ms t in
- ms, i-1, restrictions_for_n, t::l
- with Occur ->
- ms, i-1, i::restrictions_for_n, l)
- l (ms, List.length l, [], [])
- in
-
- ms, restrictions_for_n, pack_lc (shift, NCic.Ctx l)
+ let meta_chain =
+ try
+ Some (NCicUtils.lookup_subst n subst)
+ with
+ NCicUtils.Subst_not_found _ -> None
in
- if restrictions_for_n = [] then
- ms, if l = l' then orig else NCic.Meta (n, l')
- else
- let metasenv, subst, newmeta =
- restrict metasenv subst n restrictions_for_n
- in
- (metasenv, subst), NCic.Meta (newmeta, l')
+ (match meta_chain with
+ Some (_,_,bo,_) ->
+ aux k ms (NCicSubstitution.subst_meta l bo)
+ | None ->
+ (* we ignore the subst since restrict will take care of already
+ * instantiated/restricted metavariabels *)
+ let (metasenv,subst as ms), restrictions_for_n, l' =
+ let l = NCicUtils.expand_local_context lc in
+
+ let ms, _, restrictions_for_n, l =
+ List.fold_right
+ (fun t (ms, i, restrictions_for_n, l) ->
+ try
+ let ms, t = aux (k-shift) ms t in
+ ms, i-1, restrictions_for_n, t::l
+ with Occur ->
+ ms, i-1, i::restrictions_for_n, l)
+ l (ms, List.length l, [], [])
+ in
+
+ ms, restrictions_for_n, pack_lc (shift, NCic.Ctx l)
+ in
+ if restrictions_for_n = [] then
+ ms, if l = l' then orig else NCic.Meta (n, l')
+ else
+ let metasenv, subst, newmeta =
+ restrict metasenv subst n restrictions_for_n
+ in
+ (metasenv, subst), NCic.Meta (newmeta, l'))
| t -> NCicUntrusted.map_term_fold_a (fun _ k -> k+1) k aux ms t
in
aux 0 (metasenv,subst) t
| NCicUtils.Meta_not_found _ -> assert false
;;
+let rec flexible_arg context subst = function
+ | NCic.Meta (i,_) ->
+ (try
+ let _,_,t,_ = List.assoc i subst in
+ flexible_arg context subst t
+ with Not_found -> true)
+ | NCic.Appl (NCic.Meta (i,_) :: args)->
+ (try
+ let _,_,t,_ = List.assoc i subst in
+ flexible_arg context subst
+ (NCicReduction.head_beta_reduce ~delta:max_int
+ (NCic.Appl (t :: args)))
+ with Not_found -> true)
+ (* this is a cheap whd, it only performs zeta-reduction.
+ *
+ * it works when the **omissis** disambiguation algorithm
+ * is run on `let x := K a b in t`, K is substituted for a
+ * ? and thus in t metavariables have a flexible Rel
+ *)
+ | NCic.Rel i ->
+ (try
+ match List.nth context (i-1)
+ with
+ | _,NCic.Def (bo,_) ->
+ flexible_arg context subst
+ (NCicSubstitution.lift i bo)
+ | _ -> false
+ with
+ | Failure _ ->
+ prerr_endline (Printf.sprintf "Rel %d inside context:\n%s" i
+ (NCicPp.ppcontext ~subst ~metasenv:[] context));
+ assert false
+ | Invalid_argument _ -> assert false)
+ | _ -> false
+;;
+
+let is_out_scope = function `OutScope _ -> true | _ -> false;;
+let is_out_scope_tag = List.exists is_out_scope;;
+let int_of_out_scope_tag tag =
+ match List.filter is_out_scope tag with [`OutScope n] -> n | _ -> assert false
+;;
+
+
+exception Found;;
+
(* INVARIANT: we suppose that t is not another occurrence of Meta(n,_),
otherwise the occur check does not make sense in case of unification
of ?n with ?n *)
-let delift metasenv subst context n l t =
- let rec aux k (metasenv, subst as ms) = function
+let delift ~unify metasenv subst context n l t =
+ let is_in_scope_meta subst = function
+ | NCic.Meta (i,_) ->
+ (try
+ let tag, _, _, _ = NCicUtils.lookup_subst i subst in
+ List.mem `InScope tag
+ with NCicUtils.Subst_not_found _ -> false)
+ | _ -> false
+ in
+ let contains_in_scope subst t =
+ let rec aux _ () = function
+ | NCic.Meta _ as t ->
+ if is_in_scope_meta subst t then raise Found
+ else ()
+ | t ->
+ if is_in_scope_meta subst t then raise Found
+ else NCicUtils.fold (fun _ () -> ()) () aux () t
+ in
+ try aux () () t; false with Found -> true
+ in
+ let unify_list in_scope =
+ match l with
+ | _, NCic.Irl _ -> fun _ _ _ _ _ -> None
+ | shift, NCic.Ctx l -> fun metasenv subst context k t ->
+ if flexible_arg context subst t || contains_in_scope subst t then None else
+ let lb =
+ List.map (fun t ->
+ let t = NCicSubstitution.lift (k+shift) t in
+ t, flexible_arg context subst t)
+ l
+ in
+ HExtlib.list_findopt
+ (fun (li,flexible) i ->
+ if flexible || i < in_scope then None else
+ match unify metasenv subst context li t with
+ | Some (metasenv,subst) ->
+ Some ((metasenv, subst), NCic.Rel (i+1+k))
+ | None -> None)
+ lb
+ in
+ let rec aux (context,k,in_scope) (metasenv, subst as ms) t =
+ match unify_list in_scope metasenv subst context k t with
+ | Some x -> x
+ | None ->
+ match t with
| NCic.Rel n as t when n <= k -> ms, t
| NCic.Rel n ->
(try
- match List.nth context (n-k-1) with
+ match List.nth context (n-1) with
| _,NCic.Def (bo,_) ->
- (try ms, NCic.Rel ((position (n-k) l) + k)
+ (try ms, NCic.Rel ((position in_scope (n-k) l) + k)
with NotInTheList ->
(* CSC: This bit of reduction hurts performances since it is
* possible to have an exponential explosion of the size of the
* proof. required for nat/nth_prime.ma *)
- aux k ms (NCicSubstitution.lift n bo))
- | _,NCic.Decl _ -> ms, NCic.Rel ((position (n-k) l) + k)
+ aux (context,k,in_scope) ms (NCicSubstitution.lift n bo))
+ | _,NCic.Decl _ -> ms, NCic.Rel ((position in_scope (n-k) l) + k)
with Failure _ -> assert false) (*Unbound variable found in delift*)
| NCic.Meta (i,_) when i=n ->
raise (MetaSubstFailure (lazy (Printf.sprintf (
(NCicPp.ppterm ~context ~metasenv ~subst t))))
| NCic.Meta (i,l1) as orig ->
(try
- let _,_,t,_ = NCicUtils.lookup_subst i subst in
- aux k ms (NCicSubstitution.subst_meta l1 t)
+ let tag,c,t,ty = NCicUtils.lookup_subst i subst in
+ let in_scope, clear =
+ if List.mem `InScope tag then 0, true
+ else if is_out_scope_tag tag then int_of_out_scope_tag tag,true
+ else in_scope, false
+ in
+ let ms =
+ if not clear then ms
+ else
+ metasenv,
+ (i,([],c,t,ty)) :: List.filter (fun j,_ -> i <> j) subst
+ in
+ aux (context,k,in_scope) ms (NCicSubstitution.subst_meta l1 t)
with NCicUtils.Subst_not_found _ ->
if snd l1 = NCic.Irl 0 || snd l1 = NCic.Ctx [] then ms, orig
else
| t::tl ->
let ms, tbr, tl = deliftl tbr (j+1) ms tl in
try
- let ms, t = aux k ms t in
+ let ms, t = aux (context,k,in_scope) ms t in
ms, tbr, t::tl
with
| NotInTheList | MetaSubstFailure _ -> ms, j::tbr, tl
restrict metasenv subst i to_be_r in
(metasenv, subst), NCic.Meta(newmeta,l1))
- | t -> NCicUntrusted.map_term_fold_a (fun _ k -> k+1) k aux ms t
+ | t ->
+ NCicUntrusted.map_term_fold_a
+ (fun e (c,k,s) -> (e::c,k+1,s)) (context,k,in_scope) aux ms t
in
- try aux 0 (metasenv,subst) t
+(*
+ prerr_endline (
+ "DELIFTO " ^ NCicPp.ppterm ~metasenv ~subst ~context t ^ " w.r.t. " ^
+ String.concat ", " (List.map (NCicPp.ppterm ~metasenv ~subst ~context) (
+ let shift, lc = l in
+ (List.map (NCicSubstitution.lift shift)
+ (NCicUtils.expand_local_context lc))
+ )));
+*)
+ try aux (context,0,0) (metasenv,subst) t
with NotInTheList ->
(* This is the case where we fail even first order unification. *)
(* The reason is that our delift function is weaker than first *)
let lc = NCicUtils.expand_local_context lc in
let l = List.map (NCicSubstitution.lift shift) lc in
if
- List.exists
- (fun t ->
- NCicUntrusted.metas_of_term subst context t = [])
- l
+ List.exists (fun t-> NCicUntrusted.metas_of_term subst context t <> [])l
then
raise (Uncertain msg)
else
raise (MetaSubstFailure msg)
;;
-let mk_meta ?name metasenv context ty =
- match ty with
- | `Typeless ->
- let n = newmeta () in
- let ty = NCic.Implicit (`Typeof n) in
- let menv_entry = (n, (name, context, ty)) in
- menv_entry :: metasenv,NCic.Meta (n, (0,NCic.Irl (List.length context))), ty
- | `Type
- | `Term ->
- let context_for_ty = if ty = `Type then [] else context in
- let n = newmeta () in
- let ty_menv_entry = (n, (name,context_for_ty, NCic.Implicit (`Typeof n))) in
- let m = newmeta () in
- let ty = NCic.Meta (n, (0,NCic.Irl (List.length context_for_ty))) in
- let menv_entry = (m, (name, context, ty)) in
- menv_entry :: ty_menv_entry :: metasenv,
- NCic.Meta (m, (0,NCic.Irl (List.length context))), ty
+let mk_meta ?(attrs=[]) metasenv context ty =
+ let tyof = List.map (function `Name s -> `Name ("typeof_"^s) | x -> x) in
+ let rec mk_meta attrs n metasenv context = function
| `WithType ty ->
- let n = newmeta () in
let len = List.length context in
- let menv_entry = (n, (name, context, ty)) in
- menv_entry :: metasenv, NCic.Meta (n, (0,NCic.Irl len)), ty
+ let menv_entry = (n, (attrs, context, ty)) in
+ menv_entry :: metasenv, n, NCic.Meta (n, (0,NCic.Irl len)), ty
+ | `Sort ->
+ let ty = NCic.Implicit (`Typeof n) in
+ mk_meta (`IsSort::tyof attrs) n metasenv [] (`WithType ty)
+ | `Type ->
+ let metasenv, _, ty, _ =
+ mk_meta (tyof attrs) (newmeta ()) metasenv context `Sort in
+ mk_meta attrs n metasenv context (`WithType ty)
+ | `Term ->
+ let metasenv, _, ty, _ =
+ mk_meta (tyof attrs) (newmeta ()) metasenv context `Type in
+ mk_meta attrs n metasenv context (`WithType ty)
+ in
+ mk_meta attrs (newmeta ()) metasenv context ty
;;
-let saturate ?(delta=0) metasenv context ty goal_arity =
+let saturate ?(delta=0) metasenv subst context ty goal_arity =
assert (goal_arity >= 0);
let rec aux metasenv = function
- | NCic.Prod (name,s,t) ->
- let metasenv1, arg,_ =
- mk_meta ~name:name metasenv context (`WithType s) in
+ | NCic.Prod (name,s,t) as ty ->
+ let metasenv1, _, arg,_ =
+ mk_meta ~attrs:[`Name name] metasenv context (`WithType s) in
let t, metasenv1, args, pno =
aux metasenv1 (NCicSubstitution.subst arg t)
in
else
t, metasenv1, arg::args, pno+1
| ty ->
- match NCicReduction.whd context ty ~delta with
+ match NCicReduction.whd ~subst context ty ~delta with
| NCic.Prod _ as ty -> aux metasenv ty
| ty -> ty, metasenv, [], 0
in