+++ /dev/null
-(* Copyright (C) 2003, HELM Team.
- *
- *
- * This file is part of HELM, an Hypertextual, Electronic
- * Library of Mathematics, developed at the Computer Science
- * Department, University of Bologna, Italy.
- *
- * HELM is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * HELM is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with HELM; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA.
- *
- * For details, see the HELM World-Wide-Web page,
- * http://cs.unibo.it/helm/.
- *)
-
-(* $Id$ *)
-
-open Printf
-
-(* PROFILING *)
-(*
-let deref_counter = ref 0
-let apply_subst_context_counter = ref 0
-let apply_subst_metasenv_counter = ref 0
-let lift_counter = ref 0
-let subst_counter = ref 0
-let whd_counter = ref 0
-let are_convertible_counter = ref 0
-let metasenv_length = ref 0
-let context_length = ref 0
-let reset_counters () =
- apply_subst_counter := 0;
- apply_subst_context_counter := 0;
- apply_subst_metasenv_counter := 0;
- lift_counter := 0;
- subst_counter := 0;
- whd_counter := 0;
- are_convertible_counter := 0;
- metasenv_length := 0;
- context_length := 0
-let print_counters () =
- debug_print (lazy (Printf.sprintf
-"apply_subst: %d
-apply_subst_context: %d
-apply_subst_metasenv: %d
-lift: %d
-subst: %d
-whd: %d
-are_convertible: %d
-metasenv length: %d (avg = %.2f)
-context length: %d (avg = %.2f)
-"
- !apply_subst_counter !apply_subst_context_counter
- !apply_subst_metasenv_counter !lift_counter !subst_counter !whd_counter
- !are_convertible_counter !metasenv_length
- ((float !metasenv_length) /. (float !apply_subst_metasenv_counter))
- !context_length
- ((float !context_length) /. (float !apply_subst_context_counter))
- ))*)
-
-
-
-exception MetaSubstFailure of string Lazy.t
-exception Uncertain of string Lazy.t
-exception AssertFailure of string Lazy.t
-exception DeliftingARelWouldCaptureAFreeVariable;;
-
-let debug_print = fun _ -> ()
-
-type substitution = (int * (Cic.context * Cic.term)) list
-
-(*
-let rec deref subst =
- let third _,_,a = a in
- function
- Cic.Meta(n,l) as t ->
- (try
- deref subst
- (CicSubstitution.subst_meta
- l (third (CicUtil.lookup_subst n subst)))
- with
- CicUtil.Subst_not_found _ -> t)
- | t -> t
-;;
-*)
-
-let lookup_subst = CicUtil.lookup_subst
-;;
-
-(* clean_up_meta take a metasenv and a term and make every local context
-of each occurrence of a metavariable consistent with its canonical context,
-with respect to the hidden hipothesis *)
-
-(*
-let clean_up_meta subst metasenv t =
- let module C = Cic in
- let rec aux t =
- match t with
- C.Rel _
- | C.Sort _ -> t
- | C.Implicit _ -> assert false
- | C.Meta (n,l) as t ->
- let cc =
- (try
- let (cc,_) = lookup_subst n subst in cc
- with CicUtil.Subst_not_found _ ->
- try
- let (_,cc,_) = CicUtil.lookup_meta n metasenv in cc
- with CicUtil.Meta_not_found _ -> assert false) in
- let l' =
- (try
- List.map2
- (fun t1 t2 ->
- match t1,t2 with
- None , _ -> None
- | _ , t -> t) cc l
- with
- Invalid_argument _ -> assert false) in
- C.Meta (n, l')
- | C.Cast (te,ty) -> C.Cast (aux te, aux ty)
- | C.Prod (name,so,dest) -> C.Prod (name, aux so, aux dest)
- | C.Lambda (name,so,dest) -> C.Lambda (name, aux so, aux dest)
- | C.LetIn (name,so,dest) -> C.LetIn (name, aux so, aux dest)
- | C.Appl l -> C.Appl (List.map aux l)
- | C.Var (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux t)) exp_named_subst
- in
- C.Var (uri, exp_named_subst')
- | C.Const (uri, exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux t)) exp_named_subst
- in
- C.Const (uri, exp_named_subst')
- | C.MutInd (uri,tyno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux t)) exp_named_subst
- in
- C.MutInd (uri, tyno, exp_named_subst')
- | C.MutConstruct (uri,tyno,consno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux t)) exp_named_subst
- in
- C.MutConstruct (uri, tyno, consno, exp_named_subst')
- | C.MutCase (uri,tyno,out,te,pl) ->
- C.MutCase (uri, tyno, aux out, aux te, List.map aux pl)
- | C.Fix (i,fl) ->
- let fl' =
- List.map
- (fun (name,j,ty,bo) -> (name, j, aux ty, aux bo)) fl
- in
- C.Fix (i, fl')
- | C.CoFix (i,fl) ->
- let fl' =
- List.map
- (fun (name,ty,bo) -> (name, aux ty, aux bo)) fl
- in
- C.CoFix (i, fl')
- in
- aux t *)
-
-(*** Functions to apply a substitution ***)
-
-let apply_subst_gen ~appl_fun subst term =
- let rec um_aux =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel _ as t -> t
- | C.Var (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri, t) -> (uri, um_aux t)) exp_named_subst
- in
- C.Var (uri, exp_named_subst')
- | C.Meta (i, l) ->
- (try
- let (_, t,_) = lookup_subst i subst in
- um_aux (S.subst_meta l t)
- with CicUtil.Subst_not_found _ ->
- (* unconstrained variable, i.e. free in subst*)
- let l' =
- List.map (function None -> None | Some t -> Some (um_aux t)) l
- in
- C.Meta (i,l'))
- | C.Sort _
- | C.Implicit _ as t -> t
- | C.Cast (te,ty) -> C.Cast (um_aux te, um_aux ty)
- | C.Prod (n,s,t) -> C.Prod (n, um_aux s, um_aux t)
- | C.Lambda (n,s,t) -> C.Lambda (n, um_aux s, um_aux t)
- | C.LetIn (n,s,ty,t) -> C.LetIn (n, um_aux s, um_aux ty, um_aux t)
- | C.Appl (hd :: tl) -> appl_fun um_aux hd tl
- | C.Appl _ -> assert false
- | C.Const (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri, t) -> (uri, um_aux t)) exp_named_subst
- in
- C.Const (uri, exp_named_subst')
- | C.MutInd (uri,typeno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri, t) -> (uri, um_aux t)) exp_named_subst
- in
- C.MutInd (uri,typeno,exp_named_subst')
- | C.MutConstruct (uri,typeno,consno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri, t) -> (uri, um_aux t)) exp_named_subst
- in
- C.MutConstruct (uri,typeno,consno,exp_named_subst')
- | C.MutCase (sp,i,outty,t,pl) ->
- let pl' = List.map um_aux pl in
- C.MutCase (sp, i, um_aux outty, um_aux t, pl')
- | C.Fix (i, fl) ->
- let fl' =
- List.map (fun (name, i, ty, bo) -> (name, i, um_aux ty, um_aux bo)) fl
- in
- C.Fix (i, fl')
- | C.CoFix (i, fl) ->
- let fl' =
- List.map (fun (name, ty, bo) -> (name, um_aux ty, um_aux bo)) fl
- in
- C.CoFix (i, fl')
- in
- um_aux term
-;;
-
-let apply_subst =
- let appl_fun um_aux he tl =
- let tl' = List.map um_aux tl in
- let t' =
- match um_aux he with
- Cic.Appl l -> Cic.Appl (l@tl')
- | he' -> Cic.Appl (he'::tl')
- in
- begin
- match he with
- Cic.Meta (m,_) -> CicReduction.head_beta_reduce t'
- | _ -> t'
- end
- in
- fun subst t ->
-(* incr apply_subst_counter; *)
-match subst with
- [] -> t
- | _ -> apply_subst_gen ~appl_fun subst t
-;;
-
-let profiler = HExtlib.profile "U/CicMetaSubst.apply_subst"
-let apply_subst s t =
- profiler.HExtlib.profile (apply_subst s) t
-
-
-let apply_subst_context subst context =
- match subst with
- [] -> context
- | _ ->
-(*
- incr apply_subst_context_counter;
- context_length := !context_length + List.length context;
-*)
- List.fold_right
- (fun item context ->
- match item with
- | Some (n, Cic.Decl t) ->
- let t' = apply_subst subst t in
- Some (n, Cic.Decl t') :: context
- | Some (n, Cic.Def (t, ty)) ->
- let ty' = apply_subst subst ty in
- let t' = apply_subst subst t in
- Some (n, Cic.Def (t', ty')) :: context
- | None -> None :: context)
- context []
-
-let apply_subst_metasenv subst metasenv =
-(*
- incr apply_subst_metasenv_counter;
- metasenv_length := !metasenv_length + List.length metasenv;
-*)
-match subst with
- [] -> metasenv
- | _ ->
- List.map
- (fun (n, context, ty) ->
- (n, apply_subst_context subst context, apply_subst subst ty))
- (List.filter
- (fun (i, _, _) -> not (List.mem_assoc i subst))
- metasenv)
-
-(***** Pretty printing functions ******)
-
-let ppterm ~metasenv subst term =
- CicPp.ppterm ~metasenv (apply_subst subst term)
-
-let ppterm_in_context ~metasenv subst term context =
- let name_context =
- List.map (function None -> None | Some (n,_) -> Some n) context
- in
- CicPp.pp ~metasenv (apply_subst subst term) name_context
-
-let ppterm_in_context_ref = ref ppterm_in_context
-let set_ppterm_in_context f =
- ppterm_in_context_ref := f
-let use_low_level_ppterm_in_context = ref false
-
-let ppterm_in_context ~metasenv subst term context =
- if !use_low_level_ppterm_in_context then
- ppterm_in_context ~metasenv subst term context
- else
- !ppterm_in_context_ref ~metasenv subst term context
-
-let ppcontext' ~metasenv ?(sep = "\n") subst context =
- let separate s = if s = "" then "" else s ^ sep in
- List.fold_right
- (fun context_entry (i,context) ->
- match context_entry with
- Some (n,Cic.Decl t) ->
- sprintf "%s%s : %s" (separate i) (CicPp.ppname n)
- (ppterm_in_context ~metasenv subst t context),
- context_entry::context
- | Some (n,Cic.Def (bo,ty)) ->
- sprintf "%s%s : %s := %s" (separate i) (CicPp.ppname n)
- (ppterm_in_context ~metasenv subst ty context)
- (ppterm_in_context ~metasenv subst bo context),
- context_entry::context
- | None ->
- sprintf "%s_ :? _" (separate i), context_entry::context
- ) context ("",[])
-
-let ppsubst_unfolded ~metasenv subst =
- String.concat "\n"
- (List.map
- (fun (idx, (c, t,ty)) ->
- let scontext,context = ppcontext' ~metasenv ~sep:"; " subst c in
- sprintf "%s |- ?%d : %s := %s" scontext idx
-(ppterm_in_context ~metasenv [] ty context)
- (ppterm_in_context ~metasenv subst t context))
- subst)
-(*
- Printf.sprintf "?%d := %s" idx (CicPp.ppterm term))
- subst) *)
-;;
-
-let ppsubst ~metasenv subst =
- String.concat "\n"
- (List.map
- (fun (idx, (c, t, ty)) ->
- let scontext,context = ppcontext' ~metasenv ~sep:"; " [] c in
- sprintf "%s |- ?%d : %s := %s" scontext idx (ppterm_in_context ~metasenv [] ty context)
- (ppterm_in_context ~metasenv [] t context))
- subst)
-;;
-
-let ppcontext ~metasenv ?sep subst context =
- fst (ppcontext' ~metasenv ?sep subst context)
-
-let ppmetasenv ?(sep = "\n") subst metasenv =
- String.concat sep
- (List.map
- (fun (i, c, t) ->
- let scontext,context = ppcontext' ~metasenv ~sep:"; " subst c in
- sprintf "%s |- ?%d: %s" scontext i
- (ppterm_in_context ~metasenv subst t context))
- (List.filter
- (fun (i, _, _) -> not (List.mem_assoc i subst))
- metasenv))
-
-let tempi_type_of_aux_subst = ref 0.0;;
-let tempi_subst = ref 0.0;;
-let tempi_type_of_aux = ref 0.0;;
-
-(**** DELIFT ****)
-(* the delift function takes in input a metavariable index, an ordered list of
- * optional terms [t1,...,tn] and a term t, and substitutes every tk = Some
- * (rel(nk)) with rel(k). Typically, the list of optional terms is the explicit
- * substitution that is applied to a metavariable occurrence and the result of
- * the delift function is a term the implicit variable can be substituted with
- * to make the term [t] unifiable with the metavariable occurrence. In general,
- * the problem is undecidable if we consider equivalence in place of alpha
- * convertibility. Our implementation, though, is even weaker than alpha
- * convertibility, since it replace the term [tk] if and only if [tk] is a Rel
- * (missing all the other cases). Does this matter in practice?
- * The metavariable index is the index of the metavariable that must not occur
- * in the term (for occur check).
- *)
-
-exception NotInTheList;;
-
-let position n =
- let rec aux k =
- function
- [] -> raise NotInTheList
- | (Some (Cic.Rel m))::_ when m=n -> k
- | _::tl -> aux (k+1) tl in
- aux 1
-;;
-
-exception Occur;;
-
-let rec force_does_not_occur subst to_be_restricted t =
- let module C = Cic in
- let more_to_be_restricted = ref [] in
- let rec aux k = function
- C.Rel r when List.mem (r - k) to_be_restricted -> raise Occur
- | C.Rel _
- | C.Sort _ as t -> t
- | C.Implicit _ -> assert false
- | C.Meta (n, l) ->
- (* we do not retrieve the term associated to ?n in subst since *)
- (* in this way we can restrict if something goes wrong *)
- let l' =
- let i = ref 0 in
- List.map
- (function t ->
- incr i ;
- match t with
- None -> None
- | Some t ->
- try
- Some (aux k t)
- with Occur ->
- more_to_be_restricted := (n,!i) :: !more_to_be_restricted;
- None)
- l
- in
- C.Meta (n, l')
- | C.Cast (te,ty) -> C.Cast (aux k te, aux k ty)
- | C.Prod (name,so,dest) -> C.Prod (name, aux k so, aux (k+1) dest)
- | C.Lambda (name,so,dest) -> C.Lambda (name, aux k so, aux (k+1) dest)
- | C.LetIn (name,so,ty,dest) ->
- C.LetIn (name, aux k so, aux k ty, aux (k+1) dest)
- | C.Appl l -> C.Appl (List.map (aux k) l)
- | C.Var (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux k t)) exp_named_subst
- in
- C.Var (uri, exp_named_subst')
- | C.Const (uri, exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux k t)) exp_named_subst
- in
- C.Const (uri, exp_named_subst')
- | C.MutInd (uri,tyno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux k t)) exp_named_subst
- in
- C.MutInd (uri, tyno, exp_named_subst')
- | C.MutConstruct (uri,tyno,consno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (fun (uri,t) -> (uri, aux k t)) exp_named_subst
- in
- C.MutConstruct (uri, tyno, consno, exp_named_subst')
- | C.MutCase (uri,tyno,out,te,pl) ->
- C.MutCase (uri, tyno, aux k out, aux k te, List.map (aux k) pl)
- | C.Fix (i,fl) ->
- let len = List.length fl in
- let k_plus_len = k + len in
- let fl' =
- List.map
- (fun (name,j,ty,bo) -> (name, j, aux k ty, aux k_plus_len bo)) fl
- in
- C.Fix (i, fl')
- | C.CoFix (i,fl) ->
- let len = List.length fl in
- let k_plus_len = k + len in
- let fl' =
- List.map
- (fun (name,ty,bo) -> (name, aux k ty, aux k_plus_len bo)) fl
- in
- C.CoFix (i, fl')
- in
- let res = aux 0 t in
- (!more_to_be_restricted, res)
-
-let rec restrict subst to_be_restricted metasenv =
- match to_be_restricted with
- | [] -> metasenv, subst
- | _ ->
- let names_of_context_indexes context indexes =
- String.concat ", "
- (List.map
- (fun i ->
- try
- match List.nth context (i-1) with
- | None -> assert false
- | Some (n, _) -> CicPp.ppname n
- with
- Failure _ -> assert false
- ) indexes)
- in
- let force_does_not_occur_in_context to_be_restricted = function
- | None -> [], None
- | Some (name, Cic.Decl t) ->
- let (more_to_be_restricted, t') =
- force_does_not_occur subst to_be_restricted t
- in
- more_to_be_restricted, Some (name, Cic.Decl t')
- | Some (name, Cic.Def (bo, ty)) ->
- let (more_to_be_restricted, bo') =
- force_does_not_occur subst to_be_restricted bo
- in
- let more_to_be_restricted, ty' =
- let more_to_be_restricted', ty' =
- force_does_not_occur subst to_be_restricted ty
- in
- more_to_be_restricted @ more_to_be_restricted',
- ty'
- in
- more_to_be_restricted, Some (name, Cic.Def (bo', ty'))
- in
- let rec erase i to_be_restricted n = function
- | [] -> [], to_be_restricted, []
- | hd::tl ->
- let more_to_be_restricted,restricted,tl' =
- erase (i+1) to_be_restricted n tl
- in
- let restrict_me = List.mem i restricted in
- if restrict_me then
- more_to_be_restricted, restricted, None:: tl'
- else
- (try
- let more_to_be_restricted', hd' =
- let delifted_restricted =
- let rec aux =
- function
- [] -> []
- | j::tl when j > i -> (j - i)::aux tl
- | _::tl -> aux tl
- in
- aux restricted
- in
- force_does_not_occur_in_context delifted_restricted hd
- in
- more_to_be_restricted @ more_to_be_restricted',
- restricted, hd' :: tl'
- with Occur ->
- more_to_be_restricted, (i :: restricted), None :: tl')
- in
- let (more_to_be_restricted, metasenv) = (* restrict metasenv *)
- List.fold_right
- (fun (n, context, t) (more, metasenv) ->
- let to_be_restricted =
- List.map snd (List.filter (fun (m, _) -> m = n) to_be_restricted)
- in
- let (more_to_be_restricted, restricted, context') =
- (* just an optimization *)
- if to_be_restricted = [] then
- [],[],context
- else
- erase 1 to_be_restricted n context
- in
- try
- let more_to_be_restricted', t' =
- force_does_not_occur subst restricted t
- in
- let metasenv' = (n, context', t') :: metasenv in
- (more @ more_to_be_restricted @ more_to_be_restricted',
- metasenv')
- with Occur ->
- raise (MetaSubstFailure (lazy (sprintf
- "Cannot restrict the context of the metavariable ?%d over the hypotheses %s since metavariable's type depends on at least one of them"
- n (names_of_context_indexes context to_be_restricted)))))
- metasenv ([], [])
- in
- let (more_to_be_restricted', subst) = (* restrict subst *)
- List.fold_right
- (* TODO: cambiare dopo l'aggiunta del ty *)
- (fun (n, (context, term,ty)) (more, subst') ->
- let to_be_restricted =
- List.map snd (List.filter (fun (m, _) -> m = n) to_be_restricted)
- in
- (try
- let (more_to_be_restricted, restricted, context') =
- (* just an optimization *)
- if to_be_restricted = [] then
- [], [], context
- else
- erase 1 to_be_restricted n context
- in
- let more_to_be_restricted', term' =
- force_does_not_occur subst restricted term
- in
- let more_to_be_restricted'', ty' =
- force_does_not_occur subst restricted ty in
- let subst' = (n, (context', term',ty')) :: subst' in
- let more =
- more @ more_to_be_restricted
- @ more_to_be_restricted'@more_to_be_restricted'' in
- (more, subst')
- with Occur ->
- let error_msg = lazy (sprintf
- "Cannot restrict the context of the metavariable ?%d over the hypotheses %s since ?%d is already instantiated with %s and at least one of the hypotheses occurs in the substituted term"
- n (names_of_context_indexes context to_be_restricted) n
- (ppterm ~metasenv subst term))
- in
- (* DEBUG
- debug_print (lazy error_msg);
- debug_print (lazy ("metasenv = \n" ^ (ppmetasenv metasenv subst)));
- debug_print (lazy ("subst = \n" ^ (ppsubst subst)));
- debug_print (lazy ("context = \n" ^ (ppcontext subst context))); *)
- raise (MetaSubstFailure error_msg)))
- subst ([], [])
- in
- restrict subst (more_to_be_restricted @ more_to_be_restricted') metasenv
-;;
-
-(*CSC: maybe we should rename delift in abstract, as I did in my dissertation *)(*Andrea: maybe not*)
-
-let delift n subst context metasenv l t =
-(* INVARIANT: we suppose that t is not another occurrence of Meta(n,_),
- otherwise the occur check does not make sense *)
-
-(*
- debug_print (lazy ("sto deliftando il termine " ^ (CicPp.ppterm t) ^ " rispetto
- al contesto locale " ^ (CicPp.ppterm (Cic.Meta(0,l)))));
-*)
-
- let module S = CicSubstitution in
- let l =
- let (_, canonical_context, _) =
- try
- CicUtil.lookup_meta n metasenv
- with CicUtil.Meta_not_found _ ->
- raise (MetaSubstFailure (lazy
- ("delifting error: the metavariable " ^ string_of_int n ^ " is not " ^
- "declared in the metasenv")))
- in
- List.map2 (fun ct lt ->
- match (ct, lt) with
- | None, _ -> None
- | Some _, _ -> lt)
- canonical_context l
- in
- let to_be_restricted = ref [] in
- let rec deliftaux k =
- let module C = Cic in
- function
- | C.Rel m as t->
- if m <=k then
- t
- else
- (try
- match List.nth context (m-k-1) with
- Some (_,C.Def (t,_)) ->
- (try
- C.Rel ((position (m-k) l) + k)
- with
- NotInTheList ->
- (*CSC: Hmmm. This bit of reduction is not in the spirit of *)
- (*CSC: first order unification. Does it help or does it harm? *)
- (*CSC: ANSWER: it hurts performances since it is possible to *)
- (*CSC: have an exponential explosion of the size of the proof.*)
- (*CSC: However, without this bit of reduction some "apply" in *)
- (*CSC: the library fail (e.g. nat/nth_prime.ma). *)
- deliftaux k (S.lift m t))
- | Some (_,C.Decl t) ->
- C.Rel ((position (m-k) l) + k)
- | None -> raise (MetaSubstFailure (lazy "RelToHiddenHypothesis"))
- with
- Failure _ ->
- raise (MetaSubstFailure (lazy "Unbound variable found in deliftaux"))
- )
- | C.Var (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (function (uri,t) -> uri,deliftaux k t) exp_named_subst
- in
- C.Var (uri,exp_named_subst')
- | C.Meta (i, l1) as t ->
- (try
- let (_,t,_) = CicUtil.lookup_subst i subst in
- deliftaux k (CicSubstitution.subst_meta l1 t)
- with CicUtil.Subst_not_found _ ->
- (* see the top level invariant *)
- if (i = n) then
- raise (MetaSubstFailure (lazy (sprintf
- "Cannot unify the metavariable ?%d with a term that has as subterm %s in which the same metavariable occurs (occur check)"
- i (ppterm ~metasenv subst t))))
- else
- begin
- (* I do not consider the term associated to ?i in subst since *)
- (* in this way I can restrict if something goes wrong. *)
- let rec deliftl j =
- function
- [] -> []
- | None::tl -> None::(deliftl (j+1) tl)
- | (Some t)::tl ->
- let l1' = (deliftl (j+1) tl) in
- try
- Some (deliftaux k t)::l1'
- with
- NotInTheList
- | MetaSubstFailure _ ->
- to_be_restricted :=
- (i,j)::!to_be_restricted ; None::l1'
- in
- let l' = deliftl 1 l1 in
- C.Meta(i,l')
- end)
- | C.Sort _ as t -> t
- | C.Implicit _ as t -> t
- | C.Cast (te,ty) -> C.Cast (deliftaux k te, deliftaux k ty)
- | C.Prod (n,s,t) -> C.Prod (n, deliftaux k s, deliftaux (k+1) t)
- | C.Lambda (n,s,t) -> C.Lambda (n, deliftaux k s, deliftaux (k+1) t)
- | C.LetIn (n,s,ty,t) ->
- C.LetIn (n, deliftaux k s, deliftaux k ty, deliftaux (k+1) t)
- | C.Appl l -> C.Appl (List.map (deliftaux k) l)
- | C.Const (uri,exp_named_subst) ->
- let exp_named_subst' =
- List.map (function (uri,t) -> uri,deliftaux k t) exp_named_subst
- in
- C.Const (uri,exp_named_subst')
- | C.MutInd (uri,typeno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (function (uri,t) -> uri,deliftaux k t) exp_named_subst
- in
- C.MutInd (uri,typeno,exp_named_subst')
- | C.MutConstruct (uri,typeno,consno,exp_named_subst) ->
- let exp_named_subst' =
- List.map (function (uri,t) -> uri,deliftaux k t) exp_named_subst
- in
- C.MutConstruct (uri,typeno,consno,exp_named_subst')
- | C.MutCase (sp,i,outty,t,pl) ->
- C.MutCase (sp, i, deliftaux k outty, deliftaux k t,
- List.map (deliftaux k) pl)
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, i, ty, bo) ->
- (name, i, deliftaux k ty, deliftaux (k+len) bo))
- fl
- in
- C.Fix (i, liftedfl)
- | C.CoFix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, ty, bo) -> (name, deliftaux k ty, deliftaux (k+len) bo))
- fl
- in
- C.CoFix (i, liftedfl)
- in
- let res =
- try
- deliftaux 0 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 *)
- (* order (in the sense of alpha-conversion). See comment above *)
- (* related to the delift function. *)
-(* debug_print (lazy "First Order UnificationFailure during delift") ;
-debug_print(lazy (sprintf
- "Error trying to abstract %s over [%s]: the algorithm only tried to abstract over bound variables"
- (ppterm subst t)
- (String.concat "; "
- (List.map
- (function Some t -> ppterm subst t | None -> "_") l
- )))); *)
- let msg = (lazy (sprintf
- "Error trying to abstract %s over [%s]: the algorithm only tried to abstract over bound variables"
- (ppterm ~metasenv subst t)
- (String.concat "; "
- (List.map
- (function Some t -> ppterm ~metasenv subst t | None -> "_")
- l))))
- in
- if
- List.exists
- (function
- Some t -> CicUtil.is_meta_closed (apply_subst subst t)
- | None -> true) l
- then
- raise (Uncertain msg)
- else
- raise (MetaSubstFailure msg)
- in
- let (metasenv, subst) = restrict subst !to_be_restricted metasenv in
- res, metasenv, subst
-;;
-
-(* delifts a term t of n levels strating from k, that is changes (Rel m)
- * to (Rel (m - n)) when m > (k + n). if k <= m < k + n delift fails
- *)
-let delift_rels_from subst metasenv k n =
- let rec liftaux subst metasenv k =
- let module C = Cic in
- function
- C.Rel m as t ->
- if m < k then
- t, subst, metasenv
- else if m < k + n then
- raise DeliftingARelWouldCaptureAFreeVariable
- else
- C.Rel (m - n), subst, metasenv
- | C.Var (uri,exp_named_subst) ->
- let exp_named_subst',subst,metasenv =
- List.fold_right
- (fun (uri,t) (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- (uri,t')::l,subst,metasenv) exp_named_subst ([],subst,metasenv)
- in
- C.Var (uri,exp_named_subst'),subst,metasenv
- | C.Meta (i,l) ->
- (try
- let (_, t,_) = lookup_subst i subst in
- liftaux subst metasenv k (CicSubstitution.subst_meta l t)
- with CicUtil.Subst_not_found _ ->
- let l',to_be_restricted,subst,metasenv =
- let rec aux con l subst metasenv =
- match l with
- [] -> [],[],subst,metasenv
- | he::tl ->
- let tl',to_be_restricted,subst,metasenv =
- aux (con + 1) tl subst metasenv in
- let he',more_to_be_restricted,subst,metasenv =
- match he with
- None -> None,[],subst,metasenv
- | Some t ->
- try
- let t',subst,metasenv = liftaux subst metasenv k t in
- Some t',[],subst,metasenv
- with
- DeliftingARelWouldCaptureAFreeVariable ->
- None,[i,con],subst,metasenv
- in
- he'::tl',more_to_be_restricted@to_be_restricted,subst,metasenv
- in
- aux 1 l subst metasenv in
- let metasenv,subst = restrict subst to_be_restricted metasenv in
- C.Meta(i,l'),subst,metasenv)
- | C.Sort _ as t -> t,subst,metasenv
- | C.Implicit _ as t -> t,subst,metasenv
- | C.Cast (te,ty) ->
- let te',subst,metasenv = liftaux subst metasenv k te in
- let ty',subst,metasenv = liftaux subst metasenv k ty in
- C.Cast (te',ty'),subst,metasenv
- | C.Prod (n,s,t) ->
- let s',subst,metasenv = liftaux subst metasenv k s in
- let t',subst,metasenv = liftaux subst metasenv (k+1) t in
- C.Prod (n,s',t'),subst,metasenv
- | C.Lambda (n,s,t) ->
- let s',subst,metasenv = liftaux subst metasenv k s in
- let t',subst,metasenv = liftaux subst metasenv (k+1) t in
- C.Lambda (n,s',t'),subst,metasenv
- | C.LetIn (n,s,ty,t) ->
- let s',subst,metasenv = liftaux subst metasenv k s in
- let ty',subst,metasenv = liftaux subst metasenv k ty in
- let t',subst,metasenv = liftaux subst metasenv (k+1) t in
- C.LetIn (n,s',ty',t'),subst,metasenv
- | C.Appl l ->
- let l',subst,metasenv =
- List.fold_right
- (fun t (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- t'::l,subst,metasenv) l ([],subst,metasenv) in
- C.Appl l',subst,metasenv
- | C.Const (uri,exp_named_subst) ->
- let exp_named_subst',subst,metasenv =
- List.fold_right
- (fun (uri,t) (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- (uri,t')::l,subst,metasenv) exp_named_subst ([],subst,metasenv)
- in
- C.Const (uri,exp_named_subst'),subst,metasenv
- | C.MutInd (uri,tyno,exp_named_subst) ->
- let exp_named_subst',subst,metasenv =
- List.fold_right
- (fun (uri,t) (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- (uri,t')::l,subst,metasenv) exp_named_subst ([],subst,metasenv)
- in
- C.MutInd (uri,tyno,exp_named_subst'),subst,metasenv
- | C.MutConstruct (uri,tyno,consno,exp_named_subst) ->
- let exp_named_subst',subst,metasenv =
- List.fold_right
- (fun (uri,t) (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- (uri,t')::l,subst,metasenv) exp_named_subst ([],subst,metasenv)
- in
- C.MutConstruct (uri,tyno,consno,exp_named_subst'),subst,metasenv
- | C.MutCase (sp,i,outty,t,pl) ->
- let outty',subst,metasenv = liftaux subst metasenv k outty in
- let t',subst,metasenv = liftaux subst metasenv k t in
- let pl',subst,metasenv =
- List.fold_right
- (fun t (l,subst,metasenv) ->
- let t',subst,metasenv = liftaux subst metasenv k t in
- t'::l,subst,metasenv) pl ([],subst,metasenv)
- in
- C.MutCase (sp,i,outty',t',pl'),subst,metasenv
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl,subst,metasenv =
- List.fold_right
- (fun (name, i, ty, bo) (l,subst,metasenv) ->
- let ty',subst,metasenv = liftaux subst metasenv k ty in
- let bo',subst,metasenv = liftaux subst metasenv (k+len) bo in
- (name,i,ty',bo')::l,subst,metasenv
- ) fl ([],subst,metasenv)
- in
- C.Fix (i, liftedfl),subst,metasenv
- | C.CoFix (i, fl) ->
- let len = List.length fl in
- let liftedfl,subst,metasenv =
- List.fold_right
- (fun (name, ty, bo) (l,subst,metasenv) ->
- let ty',subst,metasenv = liftaux subst metasenv k ty in
- let bo',subst,metasenv = liftaux subst metasenv (k+len) bo in
- (name,ty',bo')::l,subst,metasenv
- ) fl ([],subst,metasenv)
- in
- C.CoFix (i, liftedfl),subst,metasenv
- in
- liftaux subst metasenv k
-
-let delift_rels subst metasenv n t =
- delift_rels_from subst metasenv 1 n t
-
-
-(**** END OF DELIFT ****)
-
-
-(** {2 Format-like pretty printers} *)
-
-let fpp_gen ppf s =
- Format.pp_print_string ppf s;
- Format.pp_print_newline ppf ();
- Format.pp_print_flush ppf ()
-
-let fppsubst ppf subst = fpp_gen ppf (ppsubst ~metasenv:[] subst)
-let fppterm ppf term = fpp_gen ppf (CicPp.ppterm term)
-let fppmetasenv ppf metasenv = fpp_gen ppf (ppmetasenv [] metasenv)
projects / helm.git / blobdiff