+(*
+ ||M|| This file is part of HELM, an Hypertextual, Electronic
+ ||A|| Library of Mathematics, developed at the Computer Science
+ ||T|| Department, University of Bologna, Italy.
+ ||I||
+ ||T|| HELM is free software; you can redistribute it and/or
+ ||A|| modify it under the terms of the GNU General Public License
+ \ / version 2 or (at your option) any later version.
+ \ / This software is distributed as is, NO WARRANTY.
+ V_______________________________________________________________ *)
+
+(* $Id$ *)
+
+module C = NCic
+module Ref = NReference
+module R = NCicReduction
+module S = NCicSubstitution
+module U = NCicUtils
+module E = NCicEnvironment
+module PP = NCicPp
exception TypeCheckerFailure of string Lazy.t
exception AssertFailure of string Lazy.t
-(* typechecks the object, raising an exception if illtyped *)
-let typecheck_obj obj = match obj with _ -> ()
+(*
+let raise = function
+ | TypeCheckerFailure s as e -> prerr_endline (Lazy.force s); raise e
+ | e -> raise e
+;;
+*)
+
+type recf_entry =
+ | Evil of int (* rno *)
+ | UnfFix of bool list (* fixed arguments *)
+ | Safe
+;;
+
+let is_dangerous i l =
+ List.exists (function (j,Evil _) when j=i -> true | _ -> false) l
+;;
+
+let is_unfolded i l =
+ List.exists (function (j,UnfFix _) when j=i -> true | _ -> false) l
+;;
+
+let is_safe i l =
+ List.exists (function (j,Safe) when j=i -> true | _ -> false) l
+;;
+
+let get_recno i l =
+ try match List.assoc i l with Evil rno -> rno | _ -> assert false
+ with Not_found -> assert false
+;;
+
+let get_fixed_args i l =
+ try match List.assoc i l with UnfFix fa -> fa | _ -> assert false
+ with Not_found -> assert false
+;;
+
+let shift_k e (c,rf,x) = e::c,List.map (fun (k,v) -> k+1,v) rf,x+1;;
+
+(* for debugging only
+let string_of_recfuns ~subst ~metasenv ~context l =
+ let pp = PP.ppterm ~subst ~metasenv ~context in
+ let safe, rest = List.partition (function (_,Safe) -> true | _ -> false) l in
+ let dang,unf = List.partition (function (_,UnfFix _)-> false | _->true)rest in
+ "\n\tsafes: "^String.concat "," (List.map (fun (i,_)->pp (C.Rel i)) safe) ^
+ "\n\tfix : "^String.concat ","
+ (List.map
+ (function (i,UnfFix l)-> pp(C.Rel i)^"/"^String.concat "," (List.map
+ string_of_bool l)
+ | _ ->assert false) unf) ^
+ "\n\trec : "^String.concat ","
+ (List.map
+ (function (i,Evil rno)->pp(C.Rel i)^"/"^string_of_int rno
+ | _ -> assert false) dang)
+;;
+*)
+
+let fixed_args bos j n nn =
+ let rec aux k acc = function
+ | C.Appl (C.Rel i::args) when i-k > n && i-k <= nn ->
+ let rec combine l1 l2 =
+ match l1,l2 with
+ [],[] -> []
+ | he1::tl1, he2::tl2 -> (he1,he2)::combine tl1 tl2
+ | _::tl, [] -> (false,C.Rel ~-1)::combine tl [] (* dummy term *)
+ | [],_::_ -> assert false
+ in
+ let lefts, _ = HExtlib.split_nth (min j (List.length args)) args in
+ List.map (fun ((b,x),i) -> b && x = C.Rel (k-i))
+ (HExtlib.list_mapi (fun x i -> x,i) (combine acc lefts))
+ | t -> U.fold (fun _ k -> k+1) k aux acc t
+ in
+ List.fold_left (aux 0)
+ (let rec f = function 0 -> [] | n -> true :: f (n-1) in f j) bos
+;;
+
+let debruijn uri number_of_types ~subst context =
+(* manca la subst! *)
+ let rec aux k t =
+ match t with
+ | C.Meta (i,(s,l)) ->
+ (try
+ let _,_,term,_ = U.lookup_subst i subst in
+ let ts = S.subst_meta (0,l) term in
+ let ts' = aux (k-s) ts in
+ if ts == ts' then t else ts'
+ with U.Subst_not_found _ ->
+ match l with
+ C.Ctx l ->
+ let l1 = HExtlib.sharing_map (aux (k-s)) l in
+ if l1 == l then t else C.Meta (i,(s,C.Ctx l1))
+ | _ -> t)
+ | C.Const (Ref.Ref (uri1,(Ref.Fix (no,_,_) | Ref.CoFix no)))
+ | C.Const (Ref.Ref (uri1,Ref.Ind (_,no,_))) when NUri.eq uri uri1 ->
+ C.Rel (k + number_of_types - no)
+ | t -> U.map (fun _ k -> k+1) k aux t
+ in
+ aux (List.length context)
+;;
+
+let sort_of_prod ~metasenv ~subst context (name,s) t (t1, t2) =
+ let t1 = R.whd ~subst context t1 in
+ let t2 = R.whd ~subst ((name,C.Decl s)::context) t2 in
+ match t1, t2 with
+ | C.Sort _, C.Sort C.Prop -> t2
+ | C.Sort (C.Type u1), C.Sort (C.Type u2) ->
+ C.Sort (C.Type (NCicEnvironment.max u1 u2))
+ | C.Sort C.Prop,C.Sort (C.Type _) -> t2
+ | C.Meta (_,(_,(C.Irl 0 | C.Ctx []))), C.Sort _ -> t2
+ | C.Meta (_,(_,(C.Irl 0 | C.Ctx []))), C.Meta (i,(_,(C.Irl 0 | C.Ctx [])))
+ | C.Sort _, C.Meta (i,(_,(C.Irl 0 | C.Ctx []))) ->
+ NCic.Meta (i,(0, C.Irl 0))
+ | x, (C.Sort _ | C.Meta (_,(_,(C.Irl 0 | C.Ctx []))))
+ | _, x ->
+ let y, context =
+ if x == t1 then s, context else t, ((name,C.Decl s)::context)
+ in
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "%s is expected to be a type, but its type is %s that is not a sort"
+ (PP.ppterm ~subst ~metasenv ~context y)
+ (PP.ppterm ~subst ~metasenv ~context x))))
+;;
+
+(* instantiate_parameters ps (x1:T1)...(xn:Tn)C *)
+(* returns ((x_|ps|:T_|ps|)...(xn:Tn)C){ps_1 / x1 ; ... ; ps_|ps| / x_|ps|} *)
+let rec instantiate_parameters params c =
+ match c, params with
+ | c,[] -> c
+ | C.Prod (_,_,ta), he::tl -> instantiate_parameters tl (S.subst he ta)
+ | _,_ -> raise (AssertFailure (lazy "1"))
+;;
+
+let specialize_inductive_type_constrs ~subst context ty_term =
+ match R.whd ~subst context ty_term with
+ | C.Const (Ref.Ref (_,Ref.Ind _) as ref)
+ | C.Appl (C.Const (Ref.Ref (_,Ref.Ind _) as ref) :: _ ) as ty ->
+ let args = match ty with C.Appl (_::tl) -> tl | _ -> [] in
+ let _, leftno, itl, _, i = E.get_checked_indtys ref in
+ let left_args,_ = HExtlib.split_nth leftno args in
+ let _,_,_,cl = List.nth itl i in
+ List.map
+ (fun (rel,name,ty) -> rel, name, instantiate_parameters left_args ty) cl
+ | _ -> assert false
+;;
+
+let specialize_and_abstract_constrs ~subst r_uri r_len context ty_term =
+ let cl = specialize_inductive_type_constrs ~subst context ty_term in
+ let len = List.length context in
+ let context_dcl =
+ match E.get_checked_obj r_uri with
+ | _,_,_,_, C.Inductive (_,_,tys,_) ->
+ context @ List.map (fun (_,name,arity,_) -> name,C.Decl arity) tys
+ | _ -> assert false
+ in
+ context_dcl,
+ List.map (fun (_,id,ty) -> id, debruijn r_uri r_len ~subst context ty) cl,
+ len, len + r_len
+;;
+
+exception DoesOccur;;
+
+let does_not_occur ~subst context n nn t =
+ let rec aux k _ = function
+ | C.Rel m when m > n+k && m <= nn+k -> raise DoesOccur
+ | C.Rel m when m <= k || m > nn+k -> ()
+ | C.Rel m ->
+ (try match List.nth context (m-1-k) with
+ | _,C.Def (bo,_) -> aux (n-m) () bo
+ | _ -> ()
+ with Failure _ -> assert false)
+ | C.Meta (_,(_,(C.Irl 0 | C.Ctx []))) -> (* closed meta *) ()
+ | C.Meta (mno,(s,l)) ->
+ (try
+ (* possible optimization here: try does_not_occur on l and
+ perform substitution only if DoesOccur is raised *)
+ let _,_,term,_ = U.lookup_subst mno subst in
+ aux (k-s) () (S.subst_meta (0,l) term)
+ with U.Subst_not_found _ -> match l with
+ | C.Irl len -> if not (n+k >= s+len || s > nn+k) then raise DoesOccur
+ | C.Ctx lc -> List.iter (aux (k-s) ()) lc)
+ | t -> U.fold (fun _ k -> k + 1) k aux () t
+ in
+ try aux 0 () t; true
+ with DoesOccur -> false
+;;
+
+let rec eat_lambdas ~subst ~metasenv context n te =
+ match (n, R.whd ~subst context te) with
+ | (0, _) -> (te, context)
+ | (n, C.Lambda (name,so,ta)) when n > 0 ->
+ eat_lambdas ~subst ~metasenv ((name,(C.Decl so))::context) (n - 1) ta
+ | (n, te) ->
+ raise (AssertFailure (lazy (Printf.sprintf "eat_lambdas (%d, %s)" n
+ (PP.ppterm ~subst ~metasenv ~context te))))
+;;
+
+let rec eat_or_subst_lambdas
+ ~subst ~metasenv n te to_be_subst args (context,_,_ as k)
+=
+ match n, R.whd ~subst context te, to_be_subst, args with
+ | (n, C.Lambda (_,_,ta),true::to_be_subst,arg::args) when n > 0 ->
+ eat_or_subst_lambdas ~subst ~metasenv (n - 1) (S.subst arg ta)
+ to_be_subst args k
+ | (n, C.Lambda (name,so,ta),false::to_be_subst,_::args) when n > 0 ->
+ eat_or_subst_lambdas ~subst ~metasenv (n - 1) ta to_be_subst args
+ (shift_k (name,(C.Decl so)) k)
+ | (_, te, _, _) -> te, k
+;;
+
+let check_homogeneous_call ~subst context indparamsno n uri reduct tl =
+ let last =
+ List.fold_left
+ (fun k x ->
+ if k = 0 then 0
+ else
+ match R.whd ~subst context x with
+ | C.Rel m when m = n - (indparamsno - k) -> k - 1
+ | _ -> raise (TypeCheckerFailure (lazy
+ ("Argument "^string_of_int (indparamsno - k + 1) ^ " (of " ^
+ string_of_int indparamsno ^ " fixed) is not homogeneous in "^
+ "appl:\n"^ PP.ppterm ~context ~subst ~metasenv:[] reduct))))
+ indparamsno tl
+ in
+ if last <> 0 then
+ raise (TypeCheckerFailure
+ (lazy ("Non-positive occurence in mutual inductive definition(s) [2]"^
+ NUri.string_of_uri uri)))
+;;
+
+(* Inductive types being checked for positivity have *)
+(* indexes x s.t. n < x <= nn. *)
+let rec weakly_positive ~subst context n nn uri indparamsno posuri te =
+ (*CSC: Not very nice. *)
+ let dummy = C.Sort C.Prop in
+ (*CSC: to be moved in cicSubstitution? *)
+ let rec subst_inductive_type_with_dummy _ = function
+ | C.Const (Ref.Ref (uri',Ref.Ind (true,0,_))) when NUri.eq uri' uri -> dummy
+ | C.Appl ((C.Const (Ref.Ref (uri',Ref.Ind (true,0,lno))))::tl)
+ when NUri.eq uri' uri ->
+ let _, rargs = HExtlib.split_nth lno tl in
+ if rargs = [] then dummy else C.Appl (dummy :: rargs)
+ | t -> U.map (fun _ x->x) () subst_inductive_type_with_dummy t
+ in
+ (* this function has the same semantics of are_all_occurrences_positive
+ but the i-th context entry role is played by dummy and some checks
+ are skipped because we already know that are_all_occurrences_positive
+ of uri in te. *)
+ let rec aux context n nn te =
+ match R.whd ~subst context te with
+ | t when t = dummy -> true
+ | C.Appl (te::rargs) when te = dummy ->
+ List.for_all (does_not_occur ~subst context n nn) rargs
+ | C.Prod (name,source,dest) when
+ does_not_occur ~subst ((name,C.Decl source)::context) 0 1 dest ->
+ (* dummy abstraction, so we behave as in the anonimous case *)
+ strictly_positive ~subst context n nn indparamsno posuri source &&
+ aux ((name,C.Decl source)::context) (n + 1) (nn + 1) dest
+ | C.Prod (name,source,dest) ->
+ does_not_occur ~subst context n nn source &&
+ aux ((name,C.Decl source)::context) (n + 1) (nn + 1) dest
+ | _ ->
+ raise (TypeCheckerFailure (lazy "Malformed inductive constructor type"))
+ in
+ aux context n nn (subst_inductive_type_with_dummy () te)
+
+and strictly_positive ~subst context n nn indparamsno posuri te =
+ match R.whd ~subst context te with
+ | t when does_not_occur ~subst context n nn t -> true
+ | C.Rel _ when indparamsno = 0 -> true
+ | C.Appl ((C.Rel m)::tl) as reduct when m > n && m <= nn ->
+ check_homogeneous_call ~subst context indparamsno n posuri reduct tl;
+ List.for_all (does_not_occur ~subst context n nn) tl
+ | C.Prod (name,so,ta) ->
+ does_not_occur ~subst context n nn so &&
+ strictly_positive ~subst ((name,C.Decl so)::context) (n+1) (nn+1)
+ indparamsno posuri ta
+ | C.Appl (C.Const (Ref.Ref (uri,Ref.Ind _) as r)::tl) ->
+ let _,paramsno,tyl,_,i = E.get_checked_indtys r in
+ let _,name,ity,cl = List.nth tyl i in
+ let ok = List.length tyl = 1 in
+ let params, arguments = HExtlib.split_nth paramsno tl in
+ let lifted_params = List.map (S.lift 1) params in
+ let cl =
+ List.map (fun (_,_,te) -> instantiate_parameters lifted_params te) cl
+ in
+ ok &&
+ List.for_all (does_not_occur ~subst context n nn) arguments &&
+ List.for_all
+ (weakly_positive ~subst ((name,C.Decl ity)::context) (n+1) (nn+1)
+ uri indparamsno posuri) cl
+ | _ -> false
+
+(* the inductive type indexes are s.t. n < x <= nn *)
+and are_all_occurrences_positive ~subst context uri indparamsno i n nn te =
+ match R.whd ~subst context te with
+ | C.Appl ((C.Rel m)::tl) as reduct when m = i ->
+ check_homogeneous_call ~subst context indparamsno n uri reduct tl;
+ List.for_all (does_not_occur ~subst context n nn) tl
+ | C.Rel m when m = i ->
+ if indparamsno = 0 then
+ true
+ else
+ raise (TypeCheckerFailure
+ (lazy ("Non-positive occurence in mutual inductive definition(s) [3]"^
+ NUri.string_of_uri uri)))
+ | C.Prod (name,source,dest) when
+ does_not_occur ~subst ((name,C.Decl source)::context) 0 1 dest ->
+ strictly_positive ~subst context n nn indparamsno uri source &&
+ are_all_occurrences_positive ~subst
+ ((name,C.Decl source)::context) uri indparamsno
+ (i+1) (n + 1) (nn + 1) dest
+ | C.Prod (name,source,dest) ->
+ if not (does_not_occur ~subst context n nn source) then
+ raise (TypeCheckerFailure (lazy ("Non-positive occurrence in "^
+ PP.ppterm ~context ~metasenv:[] ~subst te)));
+ are_all_occurrences_positive ~subst ((name,C.Decl source)::context)
+ uri indparamsno (i+1) (n + 1) (nn + 1) dest
+ | _ ->
+ raise
+ (TypeCheckerFailure (lazy ("Malformed inductive constructor type " ^
+ (NUri.string_of_uri uri))))
+;;
+
+exception NotGuarded of string Lazy.t;;
+
+let type_of_branch ~subst context leftno outty cons tycons =
+ let rec aux liftno context cons tycons =
+ match R.whd ~subst context tycons with
+ | C.Const (Ref.Ref (_,Ref.Ind _)) -> C.Appl [S.lift liftno outty ; cons]
+ | C.Appl (C.Const (Ref.Ref (_,Ref.Ind _))::tl) ->
+ let _,arguments = HExtlib.split_nth leftno tl in
+ C.Appl (S.lift liftno outty::arguments@[cons])
+ | C.Prod (name,so,de) ->
+ let cons =
+ match S.lift 1 cons with
+ | C.Appl l -> C.Appl (l@[C.Rel 1])
+ | t -> C.Appl [t ; C.Rel 1]
+ in
+ C.Prod (name,so, aux (liftno+1) ((name,(C.Decl so))::context) cons de)
+ | t -> raise (AssertFailure
+ (lazy ("type_of_branch, the contructor has type: " ^ NCicPp.ppterm
+ ~metasenv:[] ~context:[] ~subst:[] t)))
+ in
+ aux 0 context cons tycons
+;;
+
+
+let rec typeof ~subst ~metasenv context term =
+ let rec typeof_aux context =
+ fun t -> (*prerr_endline (PP.ppterm ~metasenv ~subst ~context t);*)
+ match t with
+ | C.Rel n ->
+ (try
+ match List.nth context (n - 1) with
+ | (_,C.Decl ty) -> S.lift n ty
+ | (_,C.Def (_,ty)) -> S.lift n ty
+ with Failure _ ->
+ raise (TypeCheckerFailure (lazy ("unbound variable " ^ string_of_int n
+ ^" under: " ^ NCicPp.ppcontext ~metasenv ~subst context))))
+ | C.Sort (C.Type [false,u]) -> C.Sort (C.Type [true, u])
+ | C.Sort (C.Type _) ->
+ raise (AssertFailure (lazy ("Cannot type an inferred type: "^
+ NCicPp.ppterm ~subst ~metasenv ~context t)))
+ | C.Sort _ -> C.Sort (C.Type NCicEnvironment.type0)
+ | C.Implicit _ -> raise (AssertFailure (lazy "Implicit found"))
+ | C.Meta (n,l) as t ->
+ let canonical_ctx,ty =
+ try
+ let _,c,_,ty = U.lookup_subst n subst in c,ty
+ with U.Subst_not_found _ -> try
+ let _,c,ty = U.lookup_meta n metasenv in c, ty
+(* match ty with C.Implicit _ -> assert false | _ -> c,ty *)
+ with U.Meta_not_found _ ->
+ raise (AssertFailure (lazy (Printf.sprintf
+ "%s not found in:\n%s" (PP.ppterm ~subst ~metasenv ~context t)
+ (PP.ppmetasenv ~subst metasenv)
+ )))
+ in
+ check_metasenv_consistency t ~subst ~metasenv context canonical_ctx l;
+ S.subst_meta l ty
+ | C.Const ref -> type_of_constant ref
+ | C.Prod (name,s,t) ->
+ let sort1 = typeof_aux context s in
+ let sort2 = typeof_aux ((name,(C.Decl s))::context) t in
+ sort_of_prod ~metasenv ~subst context (name,s) t (sort1,sort2)
+ | C.Lambda (n,s,t) ->
+ let sort = typeof_aux context s in
+ (match R.whd ~subst context sort with
+ | C.Meta _ | C.Sort _ -> ()
+ | _ ->
+ raise
+ (TypeCheckerFailure (lazy (Printf.sprintf
+ ("Not well-typed lambda-abstraction: " ^^
+ "the source %s should be a type; instead it is a term " ^^
+ "of type %s") (PP.ppterm ~subst ~metasenv ~context s)
+ (PP.ppterm ~subst ~metasenv ~context sort)))));
+ let ty = typeof_aux ((n,(C.Decl s))::context) t in
+ C.Prod (n,s,ty)
+ | C.LetIn (n,ty,t,bo) ->
+ let ty_t = typeof_aux context t in
+ let _ = typeof_aux context ty in
+ if not (R.are_convertible ~metasenv ~subst context ty_t ty) then
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ "The type of %s is %s but it is expected to be %s"
+ (PP.ppterm ~subst ~metasenv ~context t)
+ (PP.ppterm ~subst ~metasenv ~context ty_t)
+ (PP.ppterm ~subst ~metasenv ~context ty))))
+ else
+ let ty_bo = typeof_aux ((n,C.Def (t,ty))::context) bo in
+ S.subst ~avoid_beta_redexes:true t ty_bo
+ | C.Appl (he::(_::_ as args)) ->
+ let ty_he = typeof_aux context he in
+ let args_with_ty = List.map (fun t -> t, typeof_aux context t) args in
+ eat_prods ~subst ~metasenv context he ty_he args_with_ty
+ | C.Appl _ -> raise (AssertFailure (lazy "Appl of length < 2"))
+ | C.Match (Ref.Ref (_,Ref.Ind (_,tyno,_)) as r,outtype,term,pl) ->
+ let outsort = typeof_aux context outtype in
+ let _,leftno,itl,_,_ = E.get_checked_indtys r in
+ let constructorsno =
+ let _,_,_,cl = List.nth itl tyno in List.length cl
+ in
+ let parameters, arguments =
+ let ty = R.whd ~subst context (typeof_aux context term) in
+ let r',tl =
+ match ty with
+ C.Const (Ref.Ref (_,Ref.Ind _) as r') -> r',[]
+ | C.Appl (C.Const (Ref.Ref (_,Ref.Ind _) as r') :: tl) -> r',tl
+ | _ ->
+ raise
+ (TypeCheckerFailure (lazy (Printf.sprintf
+ "Case analysis: analysed term %s is not an inductive one"
+ (PP.ppterm ~subst ~metasenv ~context term)))) in
+ if not (Ref.eq r r') then
+ raise
+ (TypeCheckerFailure (lazy (Printf.sprintf
+ ("Case analysys: analysed term type is %s, but is expected " ^^
+ "to be (an application of) %s")
+ (PP.ppterm ~subst ~metasenv ~context ty)
+ (PP.ppterm ~subst ~metasenv ~context (C.Const r')))))
+ else
+ try HExtlib.split_nth leftno tl
+ with
+ Failure _ ->
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "%s is partially applied"
+ (PP.ppterm ~subst ~metasenv ~context ty)))) in
+ (* let's control if the sort elimination is allowed: [(I q1 ... qr)|B] *)
+ let sort_of_ind_type =
+ if parameters = [] then C.Const r
+ else C.Appl ((C.Const r)::parameters) in
+ let type_of_sort_of_ind_ty = typeof_aux context sort_of_ind_type in
+ check_allowed_sort_elimination ~subst ~metasenv r context
+ sort_of_ind_type type_of_sort_of_ind_ty outsort;
+ (* let's check if the type of branches are right *)
+ if List.length pl <> constructorsno then
+ raise (TypeCheckerFailure (lazy ("Wrong number of cases in a match")));
+ let j,branches_ok,p_ty, exp_p_ty =
+ List.fold_left
+ (fun (j,b,old_p_ty,old_exp_p_ty) p ->
+ if b then
+ let cons =
+ let cons = Ref.mk_constructor j r in
+ if parameters = [] then C.Const cons
+ else C.Appl (C.Const cons::parameters)
+ in
+ let ty_p = typeof_aux context p in
+ let ty_cons = typeof_aux context cons in
+ let ty_branch =
+ type_of_branch ~subst context leftno outtype cons ty_cons
+ in
+ j+1, R.are_convertible ~metasenv ~subst context ty_p ty_branch,
+ ty_p, ty_branch
+ else
+ j,false,old_p_ty,old_exp_p_ty
+ ) (1,true,C.Sort C.Prop,C.Sort C.Prop) pl
+ in
+ if not branches_ok then
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf ("Branch for constructor %s :=\n%s\n"^^
+ "has type %s\nnot convertible with %s")
+ (PP.ppterm ~subst ~metasenv ~context
+ (C.Const (Ref.mk_constructor (j-1) r)))
+ (PP.ppterm ~metasenv ~subst ~context (List.nth pl (j-2)))
+ (PP.ppterm ~metasenv ~subst ~context p_ty)
+ (PP.ppterm ~metasenv ~subst ~context exp_p_ty))));
+ let res = outtype::arguments@[term] in
+ R.head_beta_reduce (C.Appl res)
+ | C.Match _ -> assert false
+
+ (* check_metasenv_consistency checks that the "canonical" context of a
+ metavariable is consitent - up to relocation via the relocation list l -
+ with the actual context *)
+ and check_metasenv_consistency
+ ~subst ~metasenv term context canonical_context l
+ =
+ match l with
+ | shift, C.Irl n ->
+ let context = snd (HExtlib.split_nth shift context) in
+ let rec compare = function
+ | 0,_,[] -> ()
+ | 0,_,_::_
+ | _,_,[] ->
+ raise (AssertFailure (lazy (Printf.sprintf
+ "(2) Local and canonical context %s have different lengths"
+ (PP.ppterm ~subst ~context ~metasenv term))))
+ | m,[],_::_ ->
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "Unbound variable -%d in %s" m
+ (PP.ppterm ~subst ~metasenv ~context term))))
+ | m,t::tl,ct::ctl ->
+ (match t,ct with
+ (_,C.Decl t1), (_,C.Decl t2)
+ | (_,C.Def (t1,_)), (_,C.Def (t2,_))
+ | (_,C.Def (_,t1)), (_,C.Decl t2) ->
+ if not (R.are_convertible ~metasenv ~subst tl t1 t2) then
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ ("Not well typed metavariable local context for %s: " ^^
+ "%s expected, which is not convertible with %s")
+ (PP.ppterm ~subst ~metasenv ~context term)
+ (PP.ppterm ~subst ~metasenv ~context t2)
+ (PP.ppterm ~subst ~metasenv ~context t1))))
+ | _,_ ->
+ raise
+ (TypeCheckerFailure (lazy (Printf.sprintf
+ ("Not well typed metavariable local context for %s: " ^^
+ "a definition expected, but a declaration found")
+ (PP.ppterm ~subst ~metasenv ~context term)))));
+ compare (m - 1,tl,ctl)
+ in
+ compare (n,context,canonical_context)
+ | shift, lc_kind ->
+ (* we avoid useless lifting by shortening the context*)
+ let l,context = (0,lc_kind), snd (HExtlib.split_nth shift context) in
+ let lifted_canonical_context =
+ let rec lift_metas i = function
+ | [] -> []
+ | (n,C.Decl t)::tl ->
+ (n,C.Decl (S.subst_meta l (S.lift i t)))::(lift_metas (i+1) tl)
+ | (n,C.Def (t,ty))::tl ->
+ (n,C.Def ((S.subst_meta l (S.lift i t)),
+ S.subst_meta l (S.lift i ty)))::(lift_metas (i+1) tl)
+ in
+ lift_metas 1 canonical_context in
+ let l = U.expand_local_context lc_kind in
+ try
+ List.iter2
+ (fun t ct ->
+ match (t,ct) with
+ | t, (_,C.Def (ct,_)) ->
+ (*CSC: the following optimization is to avoid a possibly expensive
+ reduction that can be easily avoided and that is quite
+ frequent. However, this is better handled using levels to
+ control reduction *)
+ let optimized_t =
+ match t with
+ | C.Rel n ->
+ (try
+ match List.nth context (n - 1) with
+ | (_,C.Def (te,_)) -> S.lift n te
+ | _ -> t
+ with Failure _ -> t)
+ | _ -> t
+ in
+ if not (R.are_convertible ~metasenv ~subst context optimized_t ct)
+ then
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ ("Not well typed metavariable local context: " ^^
+ "expected a term convertible with %s, found %s")
+ (PP.ppterm ~subst ~metasenv ~context ct)
+ (PP.ppterm ~subst ~metasenv ~context t))))
+ | t, (_,C.Decl ct) ->
+ let type_t = typeof_aux context t in
+ if not (R.are_convertible ~metasenv ~subst context type_t ct) then
+ raise (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ ("Not well typed metavariable local context: "^^
+ "expected a term of type %s, found %s of type %s")
+ (PP.ppterm ~subst ~metasenv ~context ct)
+ (PP.ppterm ~subst ~metasenv ~context t)
+ (PP.ppterm ~subst ~metasenv ~context type_t))))
+ ) l lifted_canonical_context
+ with
+ | Invalid_argument "List.iter2" ->
+ raise (AssertFailure (lazy (Printf.sprintf
+ "(1) Local and canonical context %s have different lengths"
+ (PP.ppterm ~subst ~metasenv ~context term))))
+
+ in
+ typeof_aux context term
+
+and check_allowed_sort_elimination ~subst ~metasenv r =
+ let mkapp he arg =
+ match he with
+ | C.Appl l -> C.Appl (l @ [arg])
+ | t -> C.Appl [t;arg] in
+ let rec aux context ind arity1 arity2 =
+ let arity1 = R.whd ~subst context arity1 in
+ let arity2 = R.whd ~subst context arity2 in
+ match arity1,arity2 with
+ | C.Prod (name,so1,de1), C.Prod (_,so2,de2) ->
+ if not (R.are_convertible ~metasenv ~subst context so1 so2) then
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "In outtype: expected %s, found %s"
+ (PP.ppterm ~subst ~metasenv ~context so1)
+ (PP.ppterm ~subst ~metasenv ~context so2)
+ )));
+ aux ((name, C.Decl so1)::context)
+ (mkapp (S.lift 1 ind) (C.Rel 1)) de1 de2
+ | C.Sort _, C.Prod (name,so,ta) ->
+ if not (R.are_convertible ~metasenv ~subst context so ind) then
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "In outtype: expected %s, found %s"
+ (PP.ppterm ~subst ~metasenv ~context ind)
+ (PP.ppterm ~subst ~metasenv ~context so)
+ )));
+ (match arity1, R.whd ~subst ((name,C.Decl so)::context) ta with
+ | (C.Sort C.Type _, C.Sort _)
+ | (C.Sort C.Prop, C.Sort C.Prop) -> ()
+ | (C.Sort C.Prop, C.Sort C.Type _) ->
+ (* TODO: we should pass all these parameters since we
+ * have them already *)
+ let _,leftno,itl,_,i = E.get_checked_indtys r in
+ let itl_len = List.length itl in
+ let _,itname,ittype,cl = List.nth itl i in
+ let cl_len = List.length cl in
+ (* is it a singleton, non recursive and non informative
+ definition or an empty one? *)
+ if not
+ (cl_len = 0 ||
+ (itl_len = 1 && cl_len = 1 &&
+ let _,_,constrty = List.hd cl in
+ is_non_recursive_singleton
+ ~subst r itname ittype constrty &&
+ is_non_informative ~metasenv ~subst leftno constrty))
+ then
+ raise (TypeCheckerFailure (lazy
+ ("Sort elimination not allowed")));
+ | _,_ -> ())
+ | _,_ -> ()
+ in
+ aux
+
+and eat_prods ~subst ~metasenv context he ty_he args_with_ty =
+ let rec aux ty_he = function
+ | [] -> ty_he
+ | (arg, ty_arg)::tl ->
+ match R.whd ~subst context ty_he with
+ | C.Prod (_,s,t) ->
+ if R.are_convertible ~metasenv ~subst context ty_arg s then
+ aux (S.subst ~avoid_beta_redexes:true arg t) tl
+ else
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ ("Appl: wrong application of %s: the argument %s has type"^^
+ "\n%s\nbut it should have type \n%s\nContext:\n%s\n")
+ (PP.ppterm ~subst ~metasenv ~context he)
+ (PP.ppterm ~subst ~metasenv ~context arg)
+ (PP.ppterm ~subst ~metasenv ~context ty_arg)
+ (PP.ppterm ~subst ~metasenv ~context s)
+ (PP.ppcontext ~subst ~metasenv context))))
+ | _ ->
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ "Appl: %s is not a function, it cannot be applied"
+ (PP.ppterm ~subst ~metasenv ~context
+ (let res = List.length tl in
+ let eaten = List.length args_with_ty - res in
+ (C.Appl
+ (he::List.map fst
+ (fst (HExtlib.split_nth eaten args_with_ty)))))))))
+ in
+ aux ty_he args_with_ty
+
+and is_non_recursive_singleton ~subst (Ref.Ref (uri,_)) iname ity cty =
+ let ctx = [iname, C.Decl ity] in
+ let cty = debruijn uri 1 [] ~subst cty in
+ let len = List.length ctx in
+ let rec aux ctx n nn t =
+ match R.whd ~subst ctx t with
+ | C.Prod (name, src, tgt) ->
+ does_not_occur ~subst ctx n nn src &&
+ aux ((name, C.Decl src) :: ctx) (n+1) (nn+1) tgt
+ | C.Rel k | C.Appl (C.Rel k :: _) when k = nn -> true
+ | _ -> assert false
+ in
+ aux ctx (len-1) len cty
+
+and is_non_informative ~metasenv ~subst paramsno c =
+ let rec aux context c =
+ match R.whd ~subst context c with
+ | C.Prod (n,so,de) ->
+ let s = typeof ~metasenv ~subst context so in
+ s = C.Sort C.Prop && aux ((n,(C.Decl so))::context) de
+ | _ -> true in
+ let context',dx = NCicReduction.split_prods ~subst [] paramsno c in
+ aux context' dx
+
+and check_mutual_inductive_defs uri ~metasenv ~subst leftno tyl =
+ (* let's check if the arity of the inductive types are well formed *)
+ List.iter (fun (_,_,x,_) -> ignore (typeof ~subst ~metasenv [] x)) tyl;
+ (* let's check if the types of the inductive constructors are well formed. *)
+ let len = List.length tyl in
+ let tys = List.rev_map (fun (_,n,ty,_) -> (n,(C.Decl ty))) tyl in
+ ignore
+ (List.fold_right
+ (fun (it_relev,_,ty,cl) i ->
+ let context,ty_sort = NCicReduction.split_prods ~subst [] ~-1 ty in
+ let sx_context_ty_rev,_ = HExtlib.split_nth leftno (List.rev context) in
+ List.iter
+ (fun (k_relev,_,te) ->
+ let k_relev =
+ try snd (HExtlib.split_nth leftno k_relev)
+ with Failure _ -> k_relev in
+ let te = debruijn uri len [] ~subst te in
+ let context,te = NCicReduction.split_prods ~subst tys leftno te in
+ let _,chopped_context_rev =
+ HExtlib.split_nth (List.length tys) (List.rev context) in
+ let sx_context_te_rev,_ =
+ HExtlib.split_nth leftno chopped_context_rev in
+ (try
+ ignore (List.fold_left2
+ (fun context item1 item2 ->
+ let convertible =
+ match item1,item2 with
+ (_,C.Decl ty1),(_,C.Decl ty2) ->
+ R.are_convertible ~metasenv ~subst context ty1 ty2
+ | (_,C.Def (bo1,ty1)),(_,C.Def (bo2,ty2)) ->
+ R.are_convertible ~metasenv ~subst context ty1 ty2 &&
+ R.are_convertible ~metasenv ~subst context bo1 bo2
+ | _,_ -> false
+ in
+ if not convertible then
+ raise (TypeCheckerFailure (lazy
+ ("Mismatch between the left parameters of the constructor " ^
+ "and those of its inductive type")))
+ else
+ item1::context
+ ) [] sx_context_ty_rev sx_context_te_rev)
+ with Invalid_argument "List.fold_left2" -> assert false);
+ let con_sort = typeof ~subst ~metasenv context te in
+ (match R.whd ~subst context con_sort, R.whd ~subst [] ty_sort with
+ (C.Sort (C.Type u1) as s1), (C.Sort (C.Type u2) as s2) ->
+ if not (E.universe_leq u1 u2) then
+ raise
+ (TypeCheckerFailure
+ (lazy ("The type " ^ PP.ppterm ~metasenv ~subst ~context s1^
+ " of the constructor is not included in the inductive" ^
+ " type sort " ^ PP.ppterm ~metasenv ~subst ~context s2)))
+ | C.Sort _, C.Sort C.Prop
+ | C.Sort _, C.Sort C.Type _ -> ()
+ | _, _ ->
+ raise
+ (TypeCheckerFailure
+ (lazy ("Wrong constructor or inductive arity shape"))));
+ (* let's check also the positivity conditions *)
+ if
+ not
+ (are_all_occurrences_positive ~subst context uri leftno
+ (i+leftno) leftno (len+leftno) te)
+ then
+ raise
+ (TypeCheckerFailure
+ (lazy ("Non positive occurence in "^NUri.string_of_uri
+ uri)))
+ else check_relevance ~subst ~metasenv context k_relev te)
+ cl;
+ check_relevance ~subst ~metasenv [] it_relev ty;
+ i+1)
+ tyl 1)
+
+and check_relevance ~subst ~metasenv context relevance ty =
+ let error context ty =
+ raise (TypeCheckerFailure
+ (lazy ("Wrong relevance declaration: " ^
+ String.concat "," (List.map string_of_bool relevance)^
+ "\nfor type: "^PP.ppterm ~metasenv ~subst ~context ty)))
+ in
+ let rec aux context relevance ty =
+ match R.whd ~subst context ty with
+ | C.Prod (name,so,de) ->
+ let sort = typeof ~subst ~metasenv context so in
+ (match (relevance,R.whd ~subst context sort) with
+ | [],_ -> ()
+ | false::tl,C.Sort C.Prop -> aux ((name,(C.Decl so))::context) tl de
+ | true::_,C.Sort C.Prop
+ | false::_,C.Sort _
+ | false::_,C.Meta _ -> error context ty
+ | true::tl,C.Sort _
+ | true::tl,C.Meta _ -> aux ((name,(C.Decl so))::context) tl de
+ | _ -> raise (AssertFailure (lazy (Printf.sprintf
+ "Prod: the type %s of the source of %s is not a sort"
+ (PP.ppterm ~subst ~metasenv ~context sort)
+ (PP.ppterm ~subst ~metasenv ~context so)))))
+ | _ -> (match relevance with
+ | [] -> ()
+ | _::_ -> error context ty)
+ in aux context relevance ty
+
+and guarded_by_destructors r_uri r_len ~subst ~metasenv context recfuns t =
+ let recursor f k t = U.fold shift_k k (fun k () -> f k) () t in
+ let rec aux (context, recfuns, x as k) t =
+(*
+ prerr_endline ("GB:\n" ^
+ PP.ppcontext ~subst ~metasenv context^
+ PP.ppterm ~metasenv ~subst ~context t^
+ string_of_recfuns ~subst ~metasenv ~context recfuns);
+*)
+ try
+ match t with
+ | C.Rel m as t when is_dangerous m recfuns ->
+ raise (NotGuarded (lazy
+ (PP.ppterm ~subst ~metasenv ~context t ^
+ " is a partial application of a fix")))
+ | C.Appl ((C.Rel m)::tl) as t when is_dangerous m recfuns ->
+ let rec_no = get_recno m recfuns in
+ if not (List.length tl > rec_no) then
+ raise (NotGuarded (lazy
+ (PP.ppterm ~context ~subst ~metasenv t ^
+ " is a partial application of a fix")))
+ else
+ let rec_arg = List.nth tl rec_no in
+ if not (is_really_smaller r_uri r_len ~subst ~metasenv k rec_arg) then
+ raise (NotGuarded (lazy (Printf.sprintf ("Recursive call %s, %s is not"
+ ^^ " smaller.\ncontext:\n%s") (PP.ppterm ~context ~subst ~metasenv
+ t) (PP.ppterm ~context ~subst ~metasenv rec_arg)
+ (PP.ppcontext ~subst ~metasenv context))));
+ List.iter (aux k) tl
+ | C.Appl ((C.Rel m)::tl) when is_unfolded m recfuns ->
+ let fixed_args = get_fixed_args m recfuns in
+ HExtlib.list_iter_default2
+ (fun x b -> if not b then aux k x) tl false fixed_args
+ | C.Rel m ->
+ (match List.nth context (m-1) with
+ | _,C.Decl _ -> ()
+ | _,C.Def (bo,_) -> aux k (S.lift m bo))
+ | C.Meta _ -> ()
+ | C.Appl (C.Const ((Ref.Ref (uri,Ref.Fix (i,recno,_))) as r)::args) ->
+ if List.exists (fun t -> try aux k t;false with NotGuarded _ -> true) args
+ then
+ let fl,_,_ = E.get_checked_fixes_or_cofixes r in
+ let ctx_tys, bos =
+ List.split (List.map (fun (_,name,_,ty,bo) -> (name, C.Decl ty), bo) fl)
+ in
+ let fl_len = List.length fl in
+ let bos = List.map (debruijn uri fl_len context ~subst) bos in
+ let j = List.fold_left min max_int (List.map (fun (_,_,i,_,_)->i) fl) in
+ let ctx_len = List.length context in
+ (* we may look for fixed params not only up to j ... *)
+ let fa = fixed_args bos j ctx_len (ctx_len + fl_len) in
+ HExtlib.list_iter_default2
+ (fun x b -> if not b then aux k x) args false fa;
+ let context = context@ctx_tys in
+ let ctx_len = List.length context in
+ let extra_recfuns =
+ HExtlib.list_mapi (fun _ i -> ctx_len - i, UnfFix fa) ctx_tys
+ in
+ let new_k = context, extra_recfuns@recfuns, x in
+ let bos_and_ks =
+ HExtlib.list_mapi
+ (fun bo fno ->
+ let bo_and_k =
+ eat_or_subst_lambdas ~subst ~metasenv j bo fa args new_k
+ in
+ if
+ fno = i &&
+ List.length args > recno &&
+ (*case where the recursive argument is already really_smaller *)
+ is_really_smaller r_uri r_len ~subst ~metasenv k
+ (List.nth args recno)
+ then
+ let bo,(context, _, _ as new_k) = bo_and_k in
+ let bo, context' =
+ eat_lambdas ~subst ~metasenv context (recno + 1 - j) bo in
+ let new_context_part,_ =
+ HExtlib.split_nth (List.length context' - List.length context)
+ context' in
+ let k = List.fold_right shift_k new_context_part new_k in
+ let context, recfuns, x = k in
+ let k = context, (1,Safe)::recfuns, x in
+ bo,k
+ else
+ bo_and_k
+ ) bos
+ in
+ List.iter (fun (bo,k) -> aux k bo) bos_and_ks
+ | C.Match (Ref.Ref (_,Ref.Ind (true,_,_)),outtype,term,pl) as t ->
+ (match R.whd ~subst context term with
+ | C.Rel m | C.Appl (C.Rel m :: _ ) as t when is_safe m recfuns || m = x ->
+ let ty = typeof ~subst ~metasenv context term in
+ let dc_ctx, dcl, start, stop =
+ specialize_and_abstract_constrs ~subst r_uri r_len context ty in
+ let args = match t with C.Appl (_::tl) -> tl | _ -> [] in
+ aux k outtype;
+ List.iter (aux k) args;
+ List.iter2
+ (fun p (_,dc) ->
+ let rl = recursive_args ~subst ~metasenv dc_ctx start stop dc in
+ let p, k = get_new_safes ~subst k p rl in
+ aux k p)
+ pl dcl
+ | _ -> recursor aux k t)
+ | t -> recursor aux k t
+ with
+ NotGuarded _ as exc ->
+ let t' = R.whd ~delta:0 ~subst context t in
+ if t = t' then raise exc
+ else aux k t'
+ in
+ try aux (context, recfuns, 1) t
+ with NotGuarded s -> raise (TypeCheckerFailure s)
+
+and guarded_by_constructors ~subst ~metasenv context t indURI indlen nn =
+ let rec aux context n nn h te =
+ match R.whd ~subst context te with
+ | C.Rel m when m > n && m <= nn -> h
+ | C.Rel _ | C.Meta _ -> true
+ | C.Sort _
+ | C.Implicit _
+ | C.Prod _
+ | C.Const (Ref.Ref (_,Ref.Ind _))
+ | C.LetIn _ -> raise (AssertFailure (lazy "17"))
+ | C.Lambda (name,so,de) ->
+ does_not_occur ~subst context n nn so &&
+ aux ((name,C.Decl so)::context) (n + 1) (nn + 1) h de
+ | C.Appl ((C.Rel m)::tl) when m > n && m <= nn ->
+ h && List.for_all (does_not_occur ~subst context n nn) tl
+ | C.Const (Ref.Ref (_,Ref.Con _)) -> true
+ | C.Appl (C.Const (Ref.Ref (_, Ref.Con (_,j,paramsno))) :: tl) as t ->
+ let ty_t = typeof ~subst ~metasenv context t in
+ let dc_ctx, dcl, start, stop =
+ specialize_and_abstract_constrs ~subst indURI indlen context ty_t in
+ let _, dc = List.nth dcl (j-1) in
+(*
+ prerr_endline (PP.ppterm ~subst ~metasenv ~context:dc_ctx dc);
+ prerr_endline (PP.ppcontext ~subst ~metasenv dc_ctx);
+ *)
+ let rec_params = recursive_args ~subst ~metasenv dc_ctx start stop dc in
+ let rec analyse_instantiated_type rec_spec args =
+ match rec_spec, args with
+ | h::rec_spec, he::args ->
+ aux context n nn h he && analyse_instantiated_type rec_spec args
+ | _,[] -> true
+ | _ -> raise (AssertFailure (lazy
+ ("Too many args for constructor: " ^ String.concat " "
+ (List.map (fun x-> PP.ppterm ~subst ~metasenv ~context x) args))))
+ in
+ let _, args = HExtlib.split_nth paramsno tl in
+ analyse_instantiated_type rec_params args
+ | C.Appl ((C.Match (_,out,te,pl))::_)
+ | C.Match (_,out,te,pl) as t ->
+ let tl = match t with C.Appl (_::tl) -> tl | _ -> [] in
+ List.for_all (does_not_occur ~subst context n nn) tl &&
+ does_not_occur ~subst context n nn out &&
+ does_not_occur ~subst context n nn te &&
+ List.for_all (aux context n nn h) pl
+(* IMPOSSIBLE unsless we allow to pass cofix to other fix/cofix as we do for
+ higher order fix in g_b_destructors.
+
+ | C.Const (Ref.Ref (u,(Ref.Fix _| Ref.CoFix _)) as ref)
+ | C.Appl(C.Const (Ref.Ref(u,(Ref.Fix _| Ref.CoFix _)) as ref) :: _) as t ->
+ let tl = match t with C.Appl (_::tl) -> tl | _ -> [] in
+ let fl,_,_ = E.get_checked_fixes_or_cofixes ref in
+ let len = List.length fl in
+ let tys = List.map (fun (_,n,_,ty,_) -> n, C.Decl ty) fl in
+ List.for_all (does_not_occur ~subst context n nn) tl &&
+ List.for_all
+ (fun (_,_,_,_,bo) ->
+ aux (context@tys) n nn h (debruijn u len context bo))
+ fl
+*)
+ | C.Const _
+ | C.Appl _ as t -> does_not_occur ~subst context n nn t
+ in
+ aux context 0 nn false t
+
+and recursive_args ~subst ~metasenv context n nn te =
+ match R.whd ~subst context te with
+ | C.Rel _ | C.Appl _ | C.Const _ -> []
+ | C.Prod (name,so,de) ->
+ (not (does_not_occur ~subst context n nn so)) ::
+ (recursive_args ~subst ~metasenv
+ ((name,(C.Decl so))::context) (n+1) (nn + 1) de)
+ | t ->
+ raise (AssertFailure (lazy ("recursive_args:" ^ PP.ppterm ~subst
+ ~metasenv ~context:[] t)))
+
+and get_new_safes ~subst (context, recfuns, x as k) p rl =
+ match R.whd ~subst context p, rl with
+ | C.Lambda (name,so,ta), b::tl ->
+ let recfuns = (if b then [0,Safe] else []) @ recfuns in
+ get_new_safes ~subst
+ (shift_k (name,(C.Decl so)) (context, recfuns, x)) ta tl
+ | C.Meta _ as e, _ | e, [] -> e, k
+ | _ -> raise (AssertFailure (lazy "Ill formed pattern"))
+
+and is_really_smaller
+ r_uri r_len ~subst ~metasenv (context, recfuns, x as k) te
+=
+ match R.whd ~subst context te with
+ | C.Rel m when is_safe m recfuns -> true
+ | C.Lambda (name, s, t) ->
+ is_really_smaller r_uri r_len ~subst ~metasenv (shift_k (name,C.Decl s) k) t
+ | C.Appl (he::_) ->
+ is_really_smaller r_uri r_len ~subst ~metasenv k he
+ | C.Rel _
+ | C.Const (Ref.Ref (_,Ref.Con _)) -> false
+ | C.Appl []
+ | C.Const (Ref.Ref (_,Ref.Fix _)) -> assert false
+ | C.Meta _ -> true
+ | C.Match (Ref.Ref (_,Ref.Ind (isinductive,_,_)),_,term,pl) ->
+ (match term with
+ | C.Rel m | C.Appl (C.Rel m :: _ ) when is_safe m recfuns || m = x ->
+ if not isinductive then
+ List.for_all (is_really_smaller r_uri r_len ~subst ~metasenv k) pl
+ else
+ let ty = typeof ~subst ~metasenv context term in
+ let dc_ctx, dcl, start, stop =
+ specialize_and_abstract_constrs ~subst r_uri r_len context ty in
+ List.for_all2
+ (fun p (_,dc) ->
+ let rl = recursive_args ~subst ~metasenv dc_ctx start stop dc in
+ let e, k = get_new_safes ~subst k p rl in
+ is_really_smaller r_uri r_len ~subst ~metasenv k e)
+ pl dcl
+ | _ -> List.for_all (is_really_smaller r_uri r_len ~subst ~metasenv k) pl)
+ | _ -> assert false
+
+and returns_a_coinductive ~subst context ty =
+ match R.whd ~subst context ty with
+ | C.Const (Ref.Ref (uri,Ref.Ind (false,_,_)) as ref)
+ | C.Appl (C.Const (Ref.Ref (uri,Ref.Ind (false,_,_)) as ref)::_) ->
+ let _, _, itl, _, _ = E.get_checked_indtys ref in
+ Some (uri,List.length itl)
+ | C.Prod (n,so,de) ->
+ returns_a_coinductive ~subst ((n,C.Decl so)::context) de
+ | _ -> None
+
+and type_of_constant ((Ref.Ref (uri,_)) as ref) =
+ let error () =
+ raise (TypeCheckerFailure (lazy "Inconsistent cached infos in reference"))
+ in
+ match E.get_checked_obj uri, ref with
+ | (_,_,_,_,C.Inductive(isind1,lno1,tl,_)),Ref.Ref(_,Ref.Ind (isind2,i,lno2))->
+ if isind1 <> isind2 || lno1 <> lno2 then error ();
+ let _,_,arity,_ = List.nth tl i in arity
+ | (_,_,_,_,C.Inductive (_,lno1,tl,_)), Ref.Ref (_,Ref.Con (i,j,lno2)) ->
+ if lno1 <> lno2 then error ();
+ let _,_,_,cl = List.nth tl i in
+ let _,_,arity = List.nth cl (j-1) in
+ arity
+ | (_,_,_,_,C.Fixpoint (false,fl,_)), Ref.Ref (_,Ref.CoFix i) ->
+ let _,_,_,arity,_ = List.nth fl i in
+ arity
+ | (_,h1,_,_,C.Fixpoint (true,fl,_)), Ref.Ref (_,Ref.Fix (i,recno2,h2)) ->
+ let _,_,recno1,arity,_ = List.nth fl i in
+ if h1 <> h2 || recno1 <> recno2 then error ();
+ arity
+ | (_,_,_,_,C.Constant (_,_,None,ty,_)), Ref.Ref (_,Ref.Decl) -> ty
+ | (_,h1,_,_,C.Constant (_,_,Some _,ty,_)), Ref.Ref (_,Ref.Def h2) ->
+ if h1 <> h2 then error ();
+ ty
+ | _ ->
+ raise (AssertFailure
+ (lazy ("type_of_constant: environment/reference: " ^
+ Ref.string_of_reference ref)))
+
+and get_relevance ~metasenv ~subst context t args =
+ let ty = typeof ~subst ~metasenv context t in
+ let rec aux context ty = function
+ | [] -> []
+ | arg::tl -> match R.whd ~subst context ty with
+ | C.Prod (_,so,de) ->
+ let sort = typeof ~subst ~metasenv context so in
+ let new_ty = S.subst ~avoid_beta_redexes:true arg de in
+ (*prerr_endline ("so: " ^ PP.ppterm ~subst ~metasenv:[]
+ ~context so);
+ prerr_endline ("sort: " ^ PP.ppterm ~subst ~metasenv:[]
+ ~context sort);*)
+ (match R.whd ~subst context sort with
+ | C.Sort C.Prop ->
+ false::(aux context new_ty tl)
+ | C.Sort _
+ | C.Meta _ -> true::(aux context new_ty tl)
+ | _ -> raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "Prod: the type %s of the source of %s is not a sort"
+ (PP.ppterm ~subst ~metasenv ~context sort)
+ (PP.ppterm ~subst ~metasenv ~context so)))))
+ | _ ->
+ raise
+ (TypeCheckerFailure
+ (lazy (Printf.sprintf
+ "Appl: %s is not a function, it cannot be applied"
+ (PP.ppterm ~subst ~metasenv ~context
+ (let res = List.length tl in
+ let eaten = List.length args - res in
+ (C.Appl
+ (t::fst
+ (HExtlib.split_nth eaten args))))))))
+ in aux context ty args
+;;
+
+let typecheck_context ~metasenv ~subst context =
+ ignore
+ (List.fold_right
+ (fun d context ->
+ begin
+ match d with
+ _,C.Decl t -> ignore (typeof ~metasenv ~subst:[] context t)
+ | name,C.Def (te,ty) ->
+ ignore (typeof ~metasenv ~subst:[] context ty);
+ let ty' = typeof ~metasenv ~subst:[] context te in
+ if not (R.are_convertible ~metasenv ~subst context ty' ty) then
+ raise (AssertFailure (lazy (Printf.sprintf (
+ "the type of the definiens for %s in the context is not "^^
+ "convertible with the declared one.\n"^^
+ "inferred type:\n%s\nexpected type:\n%s")
+ name (PP.ppterm ~subst ~metasenv ~context ty')
+ (PP.ppterm ~subst ~metasenv ~context ty))))
+ end;
+ d::context
+ ) context [])
+;;
+
+let typecheck_metasenv metasenv =
+ ignore
+ (List.fold_left
+ (fun metasenv (i,(_,context,ty) as conj) ->
+ if List.mem_assoc i metasenv then
+ raise (TypeCheckerFailure (lazy ("duplicate meta " ^ string_of_int i ^
+ " in metasenv")));
+ typecheck_context ~metasenv ~subst:[] context;
+ ignore (typeof ~metasenv ~subst:[] context ty);
+ metasenv @ [conj]
+ ) [] metasenv)
+;;
+
+let typecheck_subst ~metasenv subst =
+ ignore
+ (List.fold_left
+ (fun subst (i,(_,context,ty,bo) as conj) ->
+ if List.mem_assoc i subst then
+ raise (AssertFailure (lazy ("duplicate meta " ^ string_of_int i ^
+ " in substitution")));
+ if List.mem_assoc i metasenv then
+ raise (AssertFailure (lazy ("meta " ^ string_of_int i ^
+ " is both in the metasenv and in the substitution")));
+ typecheck_context ~metasenv ~subst context;
+ ignore (typeof ~metasenv ~subst context ty);
+ let ty' = typeof ~metasenv ~subst context bo in
+ if not (R.are_convertible ~metasenv ~subst context ty' ty) then
+ raise (AssertFailure (lazy (Printf.sprintf (
+ "the type of the definiens for %d in the substitution is not "^^
+ "convertible with the declared one.\n"^^
+ "inferred type:\n%s\nexpected type:\n%s")
+ i
+ (PP.ppterm ~subst ~metasenv ~context ty')
+ (PP.ppterm ~subst ~metasenv ~context ty))));
+ subst @ [conj]
+ ) [] subst)
+;;
+
+let height_of_term tl =
+ let h = ref 0 in
+ let get_height (NReference.Ref (uri,_)) =
+ let _,height,_,_,_ = NCicEnvironment.get_checked_obj uri in
+ height in
+ let rec aux =
+ function
+ NCic.Meta (_,(_,NCic.Ctx l)) -> List.iter aux l
+ | NCic.Meta _ -> ()
+ | NCic.Rel _
+ | NCic.Sort _ -> ()
+ | NCic.Implicit _ -> assert false
+ | NCic.Const nref -> h := max !h (get_height nref)
+ | NCic.Prod (_,t1,t2)
+ | NCic.Lambda (_,t1,t2) -> aux t1; aux t2
+ | NCic.LetIn (_,s,ty,t) -> aux s; aux ty; aux t
+ | NCic.Appl l -> List.iter aux l
+ | NCic.Match (_,outty,t,pl) -> aux outty; aux t; List.iter aux pl
+ in
+ List.iter aux tl;
+ 1 + !h
+;;
+
+let height_of_obj_kind uri ~subst =
+ function
+ NCic.Inductive _
+ | NCic.Constant (_,_,None,_,_)
+ | NCic.Fixpoint (false,_,_) -> 0
+ | NCic.Fixpoint (true,ifl,_) ->
+ let iflno = List.length ifl in
+ height_of_term
+ (List.fold_left
+ (fun l (_,_,_,ty,bo) ->
+ let bo = debruijn uri iflno [] ~subst bo in
+ ty::bo::l
+ ) [] ifl)
+ | NCic.Constant (_,_,Some bo,ty,_) -> height_of_term [bo;ty]
+;;
+
+let typecheck_obj (uri,height,metasenv,subst,kind) =
+(*height must be checked since it is not only an optimization during reduction*)
+ let iheight = height_of_obj_kind uri ~subst kind in
+ if height <> iheight then
+ raise (TypeCheckerFailure (lazy (Printf.sprintf
+ "the declared object height (%d) is not the inferred one (%d)"
+ height iheight)));
+ typecheck_metasenv metasenv;
+ typecheck_subst ~metasenv subst;
+ match kind with
+ | C.Constant (relevance,_,Some te,ty,_) ->
+ let _ = typeof ~subst ~metasenv [] ty in
+ let ty_te = typeof ~subst ~metasenv [] te in
+ if not (R.are_convertible ~metasenv ~subst [] ty_te ty) then
+ raise (TypeCheckerFailure (lazy (Printf.sprintf (
+ "the type of the body is not convertible with the declared one.\n"^^
+ "inferred type:\n%s\nexpected type:\n%s")
+ (PP.ppterm ~subst ~metasenv ~context:[] ty_te)
+ (PP.ppterm ~subst ~metasenv ~context:[] ty))));
+ check_relevance ~subst ~metasenv [] relevance ty
+ (*check_relevance ~in_type:false ~subst ~metasenv relevance te*)
+ | C.Constant (relevance,_,None,ty,_) ->
+ ignore (typeof ~subst ~metasenv [] ty);
+ check_relevance ~subst ~metasenv [] relevance ty
+ | C.Inductive (_, leftno, tyl, _) ->
+ check_mutual_inductive_defs uri ~metasenv ~subst leftno tyl
+ | C.Fixpoint (inductive,fl,_) ->
+ let types, kl =
+ List.fold_left
+ (fun (types,kl) (relevance,name,k,ty,_) ->
+ let _ = typeof ~subst ~metasenv [] ty in
+ check_relevance ~subst ~metasenv [] relevance ty;
+ ((name,C.Decl ty)::types, k::kl)
+ ) ([],[]) fl
+ in
+ let len = List.length types in
+ let dfl, kl =
+ List.split (List.map2
+ (fun (_,_,_,_,bo) rno ->
+ let dbo = debruijn uri len [] ~subst bo in
+ dbo, Evil rno)
+ fl kl)
+ in
+ List.iter2 (fun (_,_,x,ty,_) bo ->
+ let ty_bo = typeof ~subst ~metasenv types bo in
+ if not (R.are_convertible ~metasenv ~subst types ty_bo ty)
+ then raise (TypeCheckerFailure (lazy ("(Co)Fix: ill-typed bodies")))
+ else
+ if inductive then begin
+ let m, context = eat_lambdas ~subst ~metasenv types (x + 1) bo in
+ let r_uri, r_len =
+ let he =
+ match List.hd context with _,C.Decl t -> t | _ -> assert false
+ in
+ match R.whd ~subst (List.tl context) he with
+ | C.Const (Ref.Ref (uri,Ref.Ind _) as ref)
+ | C.Appl (C.Const (Ref.Ref (uri,Ref.Ind _) as ref) :: _) ->
+ let _,_,itl,_,_ = E.get_checked_indtys ref in
+ uri, List.length itl
+ | _ -> assert false
+ in
+ (* guarded by destructors conditions D{f,k,x,M} *)
+ let rec enum_from k =
+ function [] -> [] | v::tl -> (k,v)::enum_from (k+1) tl
+ in
+ guarded_by_destructors r_uri r_len
+ ~subst ~metasenv context (enum_from (x+2) kl) m
+ end else
+ match returns_a_coinductive ~subst [] ty with
+ | None ->
+ raise (TypeCheckerFailure
+ (lazy "CoFix: does not return a coinductive type"))
+ | Some (r_uri, r_len) ->
+ (* guarded by constructors conditions C{f,M} *)
+ if not
+ (guarded_by_constructors ~subst ~metasenv types bo r_uri r_len len)
+ then
+ raise (TypeCheckerFailure
+ (lazy "CoFix: not guarded by constructors"))
+ ) fl dfl
+;;
+
+(* trust *)
+
+let trust = ref (fun _ -> false);;
+let set_trust f = trust := f
+let trust_obj obj = !trust obj
+
+
+(* web interface stuff *)
+
+let logger =
+ ref (function (`Start_type_checking _|`Type_checking_completed _|`Type_checking_interrupted _|`Type_checking_failed _|`Trust_obj _) -> ())
+;;
+
+let set_logger f = logger := f;;
+
+let typecheck_obj obj =
+ let u,_,_,_,_ = obj in
+ try
+ !logger (`Start_type_checking u);
+ typecheck_obj obj;
+ !logger (`Type_checking_completed u)
+ with
+ Sys.Break as e ->
+ !logger (`Type_checking_interrupted u);
+ raise e
+ | e ->
+ !logger (`Type_checking_failed u);
+ raise e
+;;
+
+E.set_typecheck_obj
+ (fun obj ->
+ if trust_obj obj then
+ let u,_,_,_,_ = obj in
+ !logger (`Trust_obj u)
+ else
+ typecheck_obj obj)
+;;
+
+let _ = NCicReduction.set_get_relevance get_relevance;;
+
+
+let indent = ref 0;;
+let debug = true;;
+let logger =
+ let do_indent () = String.make !indent ' ' in
+ (function
+ | `Start_type_checking s ->
+ if debug then
+ prerr_endline (do_indent () ^ "Start: " ^ NUri.string_of_uri s);
+ incr indent
+ | `Type_checking_completed s ->
+ decr indent;
+ if debug then
+ prerr_endline (do_indent () ^ "End: " ^ NUri.string_of_uri s)
+ | `Type_checking_interrupted s ->
+ decr indent;
+ if debug then
+ prerr_endline (do_indent () ^ "Break: " ^ NUri.string_of_uri s)
+ | `Type_checking_failed s ->
+ decr indent;
+ if debug then
+ prerr_endline (do_indent () ^ "Fail: " ^ NUri.string_of_uri s)
+ | `Trust_obj s ->
+ if debug then
+ prerr_endline (do_indent () ^ "Trust: " ^ NUri.string_of_uri s))
+;;
+(* let _ = set_logger logger ;; *)
+(* EOF *)
projects / helm.git / blobdiff