| _ -> NCic.Appl (hd :: tl))
;;
-let flexible l =
- List.exists
- (function
- | NCic.Meta _
- | NCic.Appl (NCic.Meta _::_) -> true
- | _ -> false) l
-;;
-
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 "NU 1" (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;;
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
+ | Some 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 lambda_intros metasenv subst context t args =
+ let tty = NCicTypeChecker.typeof ~metasenv ~subst context t in
+ let argsty = List.map (NCicTypeChecker.typeof ~metasenv ~subst context) args in
+ let rec mk_lambda context n = function
+ | [] ->
+ let metasenv, _, bo, _ =
+ NCicMetaSubst.mk_meta metasenv context
+ (`WithType (NCicSubstitution.lift n tty))
+ in
+ metasenv, bo
+ | ty::tail ->
+ let name = "HBeta"^string_of_int n in
+ let ty = NCicSubstitution.lift n ty in
+ let metasenv, bo = mk_lambda ((name,NCic.Decl ty)::context) (n+1) tail in
+ metasenv, NCic.Lambda (name, ty, bo)
+ in
+ mk_lambda context 0 argsty
and instantiate hdb test_eq_only metasenv subst context n lc t swap =
(*D*) inside 'I'; try let rc =
pp msg; 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 _ ->
+ raise (UnificationFailure
+ (lazy "trying to unify a term with a type"))
+ | ty_t ->
+ 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
in
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)
let term2 = NCicSubstitution.subst_meta lc2 term in
unify hdb test_eq_only metasenv subst context term1 term2
with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg))
+
+ | _, 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)::args) when
+ not (NCicMetaSubst.flexible subst args)
+ ->
+ let metasenv, lambda_Mj =
+ lambda_intros metasenv subst context t1 args
+ in
+ unify hdb test_eq_only metasenv subst context
+ (C.Meta (i,l)) lambda_Mj,
+ i
+ | NCic.Meta (i,_) -> (metasenv, subst), i
+ | _ -> assert false
+ 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 hdb test_eq_only metasenv subst context j lj t2 true
+ 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))
| C.Meta (n,lc), t ->
(try
with Invalid_argument _ ->
raise (fail_exc metasenv subst context t1 t2))
- | NCic.Appl (NCic.Meta (i,l)::args), _ when not (flexible args) ->
+ | NCic.Appl (NCic.Meta (i,l)::args), _ when
+ not (NCicMetaSubst.flexible subst 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
+ let metasenv, lambda_Mj =
+ lambda_intros metasenv subst context t1 args
in
+ let metasenv, subst =
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
+ (C.Meta (i,l)) lambda_Mj
+ in
+ let metasenv, subst =
+ unify hdb 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) when
+ not(NCicMetaSubst.flexible subst args) ->
+ let metasenv, lambda_Mj =
+ lambda_intros metasenv subst context t2 args
in
+ let metasenv, subst =
unify hdb test_eq_only metasenv subst context
- beta_expanded (C.Meta (i,l))
+ lambda_Mj (C.Meta (i,l))
+ in
+ let metasenv, subst =
+ unify hdb 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))
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
+ let relevance =
+ try snd (HExtlib.split_nth "NU 2" lno relevance)
+ with Failure _ -> []
+ in
HExtlib.mk_list false lno @ relevance
| _ -> relevance
in
(*D*) in outside(); rc with exn -> outside (); raise exn
in
let try_hints metasenv subst t1 t2 (* exc*) =
+(*
+ prerr_endline ("\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
in
let rec cand_iter = function
| [] -> None (* raise exc *)
- | (metasenv,c1,c2)::tl ->
+ | (metasenv,(c1,c2),premises)::tl ->
+(*
+ prerr_endline ("\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
+ 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
+ let metasenv,subst =
+ List.fold_left
+ (fun (metasenv, subst) (x,y) ->
+ unify hdb test_eq_only metasenv subst context x y)
+ (metasenv, subst) premises
+ in
Some (metasenv, subst)
with
- UnificationFailure _ | Uncertain _ -> cand_iter tl
+ UnificationFailure _ | Uncertain _ ->
+ cand_iter tl
in
cand_iter candidates
in
(*D*) in outside(); rc with exn -> outside (); raise exn
in
try fo_unif test_eq_only metasenv subst t1 t2
- with UnificationFailure msg | Uncertain msg as exn ->
+ with
+ | UnificationFailure msg as exn ->
+ (try
+ unif_machines metasenv subst
+ (put_in_whd (0,[],t1,[]) (0,[],t2,[]))
+ with
+ | UnificationFailure _ -> raise (UnificationFailure msg)
+ | Uncertain _ -> raise exn)
+ | Uncertain msg as exn ->
match try_hints metasenv subst t1 t2 with
| Some x -> x
| None ->
(*D*) in outside(); rc with exn -> outside (); raise exn
;;
-let unify hdb =
+let unify hdb ?(test_eq_only=false) =
indent := "";
- unify hdb false;;
-
-
+ unify hdb test_eq_only;;
projects / helm.git / blobdiff