* http://cs.unibo.it/helm/.
*)
-exception UnificationFailed;;
-(*CSC: Vecchia unificazione: exception Impossible;;*)
-exception Free;;
-exception OccurCheck;;
+open Printf
-type substitution = (int * Cic.term) list
+exception UnificationFailure of string Lazy.t;;
+exception Uncertain of string Lazy.t;;
+exception AssertFailure of string Lazy.t;;
-(*CSC: Hhhmmm. Forse dovremmo spostarla in CicSubstitution dove si trova la *)
-(*CSC: lift? O creare una proofEngineSubstitution? *)
-(* the function delift n m un-lifts a lambda term m of n level of abstractions.
- It returns an exception Free if M contains a free variable in the range 1--n *)
-let delift n =
- let rec deliftaux k =
- let module C = Cic in
- function
- C.Rel m ->
- if m < k then C.Rel m else
- if m < k+n then raise Free
- else C.Rel (m - n)
- | C.Var _ as t -> t
- | C.Meta _ as t -> t
- | 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,t) -> C.LetIn (n, deliftaux k s, deliftaux (k+1) t)
- | C.Appl l -> C.Appl (List.map (deliftaux k) l)
- | C.Const _ as t -> t
- | C.Abst _ as t -> t
- | C.MutInd _ as t -> t
- | C.MutConstruct _ as t -> t
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- C.MutCase (sp, cookingsno, 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
- if n = 0 then
- (function t -> t)
- else
- deliftaux 1
+let verbose = false;;
+let debug_print = fun _ -> ()
+
+let profiler_toa = HExtlib.profile "fo_unif_subst.type_of_aux'"
+let profiler_beta_expand = HExtlib.profile "fo_unif_subst.beta_expand"
+let profiler_deref = HExtlib.profile "fo_unif_subst.deref'"
+let profiler_are_convertible = HExtlib.profile "fo_unif_subst.are_convertible"
+
+let type_of_aux' metasenv subst context term ugraph =
+let foo () =
+ try
+ CicTypeChecker.type_of_aux' ~subst metasenv context term ugraph
+ with
+ CicTypeChecker.TypeCheckerFailure msg ->
+ let msg =
+ lazy
+ (sprintf
+ "Kernel Type checking error:
+%s\n%s\ncontext=\n%s\nmetasenv=\n%s\nsubstitution=\n%s\nException:\n%s.\nToo bad."
+ (CicMetaSubst.ppterm subst term)
+ (CicMetaSubst.ppterm [] term)
+ (CicMetaSubst.ppcontext subst context)
+ (CicMetaSubst.ppmetasenv subst metasenv)
+ (CicMetaSubst.ppsubst subst) (Lazy.force msg)) in
+ raise (AssertFailure msg)
+ | CicTypeChecker.AssertFailure msg ->
+ let msg = lazy
+ (sprintf
+ "Kernel Type checking assertion failure:
+%s\n%s\ncontext=\n%s\nmetasenv=\n%s\nsubstitution=\n%s\nException:\n%s.\nToo bad."
+ (CicMetaSubst.ppterm subst term)
+ (CicMetaSubst.ppterm [] term)
+ (CicMetaSubst.ppcontext subst context)
+ (CicMetaSubst.ppmetasenv subst metasenv)
+ (CicMetaSubst.ppsubst subst) (Lazy.force msg)) in
+ raise (AssertFailure msg)
+in profiler_toa.HExtlib.profile foo ()
;;
-(* Questa funzione non serve piu'... per il momento la lascio *)
-(*
-let closed_up_to_n n m =
- let rec closed_aux k =
- let module C = Cic in
- function
- C.Rel m -> if m > k then () else raise Free
- | C.Var _
- | C.Meta _ (* we assume Meta are closed up to k; note that during
- meta-unfolding we shall need to properly lift the
- "body" of Metavariables *)
- | C.Sort _
- | C.Implicit -> ()
- | C.Cast (te,ty) -> closed_aux k te; closed_aux k ty
- | C.Prod (n,s,t) -> closed_aux k s; closed_aux (k+1) t
- | C.Lambda (n,s,t) -> closed_aux k s; closed_aux (k+1) t
- | C.LetIn (n,s,t) -> closed_aux k s; closed_aux (k+1) t
- | C.Appl l -> List.iter (closed_aux k) l
- | C.Const _
- | C.Abst _
- | C.MutInd _
- | C.MutConstruct _ -> ()
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- closed_aux k outty; closed_aux k t;
- List.iter (closed_aux k) pl
- | C.Fix (i, fl) ->
- let len = List.length fl in
- List.iter
- (fun (name, i, ty, bo) -> closed_aux k ty; closed_aux (k+len) bo)
- fl
- | C.CoFix (i, fl) ->
- let len = List.length fl in
- List.iter
- (fun (name, ty, bo) -> closed_aux k ty; closed_aux (k+len) bo)
- fl
- in
- if n = 0 then true
- else
- try closed_aux n m; true
- with Free -> false
-;; *)
+let exists_a_meta l =
+ List.exists (function Cic.Meta _ -> true | _ -> false) l
+
+let rec deref subst t =
+ let snd (_,a,_) = a in
+ match t with
+ Cic.Meta(n,l) ->
+ (try
+ deref subst
+ (CicSubstitution.subst_meta
+ l (snd (CicUtil.lookup_subst n subst)))
+ with
+ CicUtil.Subst_not_found _ -> t)
+ | Cic.Appl(Cic.Meta(n,l)::args) ->
+ (match deref subst (Cic.Meta(n,l)) with
+ | Cic.Lambda _ as t ->
+ deref subst (CicReduction.head_beta_reduce (Cic.Appl(t::args)))
+ | r -> Cic.Appl(r::args))
+ | Cic.Appl(((Cic.Lambda _) as t)::args) ->
+ deref subst (CicReduction.head_beta_reduce (Cic.Appl(t::args)))
+ | t -> t
+;;
+
+let deref subst t =
+ let foo () = deref subst t
+ in profiler_deref.HExtlib.profile foo ()
+
+exception WrongShape;;
+let eta_reduce after_beta_expansion after_beta_expansion_body
+ before_beta_expansion
+ =
+ try
+ match before_beta_expansion,after_beta_expansion_body with
+ Cic.Appl l, Cic.Appl l' ->
+ let rec all_but_last check_last =
+ function
+ [] -> assert false
+ | [Cic.Rel 1] -> []
+ | [_] -> if check_last then raise WrongShape else []
+ | he::tl -> he::(all_but_last check_last tl)
+ in
+ let all_but_last check_last l =
+ match all_but_last check_last l with
+ [] -> assert false
+ | [he] -> he
+ | l -> Cic.Appl l
+ in
+ let t = CicSubstitution.subst (Cic.Rel (-1)) (all_but_last true l') in
+ let all_but_last = all_but_last false l in
+ (* here we should test alpha-equivalence; however we know by
+ construction that here alpha_equivalence is equivalent to = *)
+ if t = all_but_last then
+ all_but_last
+ else
+ after_beta_expansion
+ | _,_ -> after_beta_expansion
+ with
+ WrongShape -> after_beta_expansion
+
+let rec beta_expand test_equality_only metasenv subst context t arg ugraph =
+ let module S = CicSubstitution in
+ let module C = Cic in
+let foo () =
+ let rec aux metasenv subst n context t' ugraph =
+ try
+
+ let subst,metasenv,ugraph1 =
+ fo_unif_subst test_equality_only subst context metasenv
+ (CicSubstitution.lift n arg) t' ugraph
+
+ in
+ subst,metasenv,C.Rel (1 + n),ugraph1
+ with
+ Uncertain _
+ | UnificationFailure _ ->
+ match t' with
+ | C.Rel m -> subst,metasenv,
+ (if m <= n then C.Rel m else C.Rel (m+1)),ugraph
+ | C.Var (uri,exp_named_subst) ->
+ let subst,metasenv,exp_named_subst',ugraph1 =
+ aux_exp_named_subst metasenv subst n context exp_named_subst ugraph
+ in
+ subst,metasenv,C.Var (uri,exp_named_subst'),ugraph1
+ | C.Meta (i,l) ->
+ (* 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 *)
+ let l =
+ List.map
+ (function
+ Some t -> Some (CicSubstitution.lift 1 t)
+ | None -> None) l in
+ subst, metasenv, C.Meta (i,l), ugraph
+ | C.Sort _
+ | C.Implicit _ as t -> subst,metasenv,t,ugraph
+ | C.Cast (te,ty) ->
+ let subst,metasenv,te',ugraph1 =
+ aux metasenv subst n context te ugraph in
+ let subst,metasenv,ty',ugraph2 =
+ aux metasenv subst n context ty ugraph1 in
+ (* TASSI: sure this is in serial? *)
+ subst,metasenv,(C.Cast (te', ty')),ugraph2
+ | C.Prod (nn,s,t) ->
+ let subst,metasenv,s',ugraph1 =
+ aux metasenv subst n context s ugraph in
+ let subst,metasenv,t',ugraph2 =
+ aux metasenv subst (n+1) ((Some (nn, C.Decl s))::context) t
+ ugraph1
+ in
+ (* TASSI: sure this is in serial? *)
+ subst,metasenv,(C.Prod (nn, s', t')),ugraph2
+ | C.Lambda (nn,s,t) ->
+ let subst,metasenv,s',ugraph1 =
+ aux metasenv subst n context s ugraph in
+ let subst,metasenv,t',ugraph2 =
+ aux metasenv subst (n+1) ((Some (nn, C.Decl s))::context) t ugraph1
+ in
+ (* TASSI: sure this is in serial? *)
+ subst,metasenv,(C.Lambda (nn, s', t')),ugraph2
+ | C.LetIn (nn,s,t) ->
+ let subst,metasenv,s',ugraph1 =
+ aux metasenv subst n context s ugraph in
+ let subst,metasenv,t',ugraph2 =
+ aux metasenv subst (n+1) ((Some (nn, C.Def (s,None)))::context) t
+ ugraph1
+ in
+ (* TASSI: sure this is in serial? *)
+ subst,metasenv,(C.LetIn (nn, s', t')),ugraph2
+ | C.Appl l ->
+ let subst,metasenv,revl',ugraph1 =
+ List.fold_left
+ (fun (subst,metasenv,appl,ugraph) t ->
+ let subst,metasenv,t',ugraph1 =
+ aux metasenv subst n context t ugraph in
+ subst,metasenv,(t'::appl),ugraph1
+ ) (subst,metasenv,[],ugraph) l
+ in
+ subst,metasenv,(C.Appl (List.rev revl')),ugraph1
+ | C.Const (uri,exp_named_subst) ->
+ let subst,metasenv,exp_named_subst',ugraph1 =
+ aux_exp_named_subst metasenv subst n context exp_named_subst ugraph
+ in
+ subst,metasenv,(C.Const (uri,exp_named_subst')),ugraph1
+ | C.MutInd (uri,i,exp_named_subst) ->
+ let subst,metasenv,exp_named_subst',ugraph1 =
+ aux_exp_named_subst metasenv subst n context exp_named_subst ugraph
+ in
+ subst,metasenv,(C.MutInd (uri,i,exp_named_subst')),ugraph1
+ | C.MutConstruct (uri,i,j,exp_named_subst) ->
+ let subst,metasenv,exp_named_subst',ugraph1 =
+ aux_exp_named_subst metasenv subst n context exp_named_subst ugraph
+ in
+ subst,metasenv,(C.MutConstruct (uri,i,j,exp_named_subst')),ugraph1
+ | C.MutCase (sp,i,outt,t,pl) ->
+ let subst,metasenv,outt',ugraph1 =
+ aux metasenv subst n context outt ugraph in
+ let subst,metasenv,t',ugraph2 =
+ aux metasenv subst n context t ugraph1 in
+ let subst,metasenv,revpl',ugraph3 =
+ List.fold_left
+ (fun (subst,metasenv,pl,ugraph) t ->
+ let subst,metasenv,t',ugraph1 =
+ aux metasenv subst n context t ugraph in
+ subst,metasenv,(t'::pl),ugraph1
+ ) (subst,metasenv,[],ugraph2) pl
+ in
+ subst,metasenv,(C.MutCase (sp,i,outt', t', List.rev revpl')),ugraph3
+ (* TASSI: not sure this is serial *)
+ | C.Fix (i,fl) ->
+(*CSC: not implemented
+ let tylen = List.length fl in
+ let substitutedfl =
+ List.map
+ (fun (name,i,ty,bo) -> (name, i, aux n ty, aux (n+tylen) bo))
+ fl
+ in
+ C.Fix (i, substitutedfl)
+*)
+ subst,metasenv,(CicSubstitution.lift 1 t' ),ugraph
+ | C.CoFix (i,fl) ->
+(*CSC: not implemented
+ let tylen = List.length fl in
+ let substitutedfl =
+ List.map
+ (fun (name,ty,bo) -> (name, aux n ty, aux (n+tylen) bo))
+ fl
+ in
+ C.CoFix (i, substitutedfl)
+
+*)
+ subst,metasenv,(CicSubstitution.lift 1 t'), ugraph
+
+ and aux_exp_named_subst metasenv subst n context ens ugraph =
+ List.fold_right
+ (fun (uri,t) (subst,metasenv,l,ugraph) ->
+ let subst,metasenv,t',ugraph1 = aux metasenv subst n context t ugraph in
+ subst,metasenv,((uri,t')::l),ugraph1) ens (subst,metasenv,[],ugraph)
+ in
+ let argty,ugraph1 = type_of_aux' metasenv subst context arg ugraph in
+ let fresh_name =
+ FreshNamesGenerator.mk_fresh_name ~subst
+ metasenv context (Cic.Name "Hbeta") ~typ:argty
+ in
+ let subst,metasenv,t',ugraph2 = aux metasenv subst 0 context t ugraph1 in
+ let t'' = eta_reduce (C.Lambda (fresh_name,argty,t')) t' t in
+ subst, metasenv, t'', ugraph2
+in profiler_beta_expand.HExtlib.profile foo ()
+
+
+and beta_expand_many test_equality_only metasenv subst context t args ugraph =
+ let subst,metasenv,hd,ugraph =
+ List.fold_right
+ (fun arg (subst,metasenv,t,ugraph) ->
+ let subst,metasenv,t,ugraph1 =
+ beta_expand test_equality_only
+ metasenv subst context t arg ugraph
+ in
+ subst,metasenv,t,ugraph1
+ ) args (subst,metasenv,t,ugraph)
+ in
+ subst,metasenv,hd,ugraph
+
(* NUOVA UNIFICAZIONE *)
(* A substitution is a (int * Cic.term) list that associates a
metavariable i with its body.
A metaenv is a (int * Cic.term) list that associate a metavariable
i with is type.
- fo_unif_new takes a metasenv, a context,
- two terms t1 and t2 and gives back a new
- substitution which is _NOT_ unwinded. It must be unwinded before
+ fo_unif_new takes a metasenv, a context, two terms t1 and t2 and gives back
+ a new substitution which is _NOT_ unwinded. It must be unwinded before
applying it. *)
-
-let fo_unif_new metasenv context t1 t2 =
- let module C = Cic in
- let module R = CicReduction in
- let module S = CicSubstitution in
- let rec fo_unif_aux subst k t1 t2 =
- match (t1, t2) with
- (C.Meta n, C.Meta m) -> if n == m then subst
- else let subst'=
- let tn = try List.assoc n subst
- with Not_found -> C.Meta n in
- let tm = try List.assoc m subst
- with Not_found -> C.Meta m in
- (match (tn, tm) with
- (C.Meta n, C.Meta m) -> if n==m then subst
- else if n<m
- then (m, C.Meta n)::subst
- else (n, C.Meta m)::subst
- | (C.Meta n, tm) -> (n, tm)::subst
- | (tn, C.Meta m) -> (m, tn)::subst
- | (tn,tm) -> fo_unif_aux subst 0 tn tm) in
- (* unify types first *)
- let tyn = List.assoc n metasenv in
- let tym = List.assoc m metasenv in
- fo_unif_aux subst' 0 tyn tym
- | (C.Meta n, t)
- | (t, C.Meta n) -> (* unify types first *)
- let t' = delift k t in
- let subst' =
- (try fo_unif_aux subst 0 (List.assoc n subst) t'
- with Not_found -> (n, t')::subst) in
- let tyn = List.assoc n metasenv in
- let tyt = CicTypeChecker.type_of_aux' metasenv context t' in
- fo_unif_aux subst' 0 tyn tyt
- | (C.Rel _, _)
- | (_, C.Rel _)
- | (C.Var _, _)
- | (_, C.Var _)
- | (C.Sort _ ,_)
- | (_, C.Sort _)
- | (C.Implicit, _)
- | (_, C.Implicit) -> if R.are_convertible t1 t2 then subst
- else raise UnificationFailed
- | (C.Cast (te,ty), t2) -> fo_unif_aux subst k te t2
- | (t1, C.Cast (te,ty)) -> fo_unif_aux subst k t1 te
- | (C.Prod (_,s1,t1), C.Prod (_,s2,t2)) ->
- let subst' = fo_unif_aux subst k s1 s2 in
- fo_unif_aux subst' (k+1) t1 t2
- | (C.Lambda (_,s1,t1), C.Lambda (_,s2,t2)) ->
- let subst' = fo_unif_aux subst k s1 s2 in
- fo_unif_aux subst' (k+1) t1 t2
- | (C.LetIn (_,s1,t1), t2) -> fo_unif_aux subst k (S.subst s1 t1) t2
- | (t1, C.LetIn (_,s2,t2)) -> fo_unif_aux subst k t1 (S.subst s2 t2)
- | (C.Appl l1, C.Appl l2) ->
- let lr1 = List.rev l1 in
- let lr2 = List.rev l2 in
- let rec fo_unif_l subst = function
- [],_
- | _,[] -> assert false
- | ([h1],[h2]) -> fo_unif_aux subst k h1 h2
- | ([h],l)
- | (l,[h]) -> fo_unif_aux subst k h (C.Appl l)
- | ((h1::l1),(h2::l2)) ->
- let subst' = fo_unif_aux subst k h1 h2 in
- fo_unif_l subst' (l1,l2)
- in
- fo_unif_l subst (lr1, lr2)
- | (C.Const _, _)
- | (_, C.Const _)
- | (C.Abst _, _)
- | (_, C.Abst _)
- | (C.MutInd _, _)
- | (_, C.MutInd _)
- | (C.MutConstruct _, _)
- | (_, C.MutConstruct _) -> if R.are_convertible t1 t2 then subst
- else raise UnificationFailed
- | (C.MutCase (_,_,_,outt1,t1,pl1), C.MutCase (_,_,_,outt2,t2,pl2))->
- let subst' = fo_unif_aux subst k outt1 outt2 in
- let subst'' = fo_unif_aux subst' k t1 t2 in
- List.fold_left2 (function subst -> fo_unif_aux subst k) subst'' pl1 pl2
- | (C.Fix _, _)
- | (_, C.Fix _)
- | (C.CoFix _, _)
- | (_, C.CoFix _) -> if R.are_convertible t1 t2 then subst
- else raise UnificationFailed
- | (_,_) -> raise UnificationFailed
- in fo_unif_aux [] 0 t1 t2;;
-(* VECCHIA UNIFICAZIONE -- molto piu' bella, alas *)
-(*
-let fo_unif_mgu k t1 t2 mgu =
- let module C = Cic in
- let module R = CicReduction in
- let module S = CicSubstitution in
- let rec deref n = match mgu.(n) with
- C.Meta m as t -> if n = m then t else (deref m)
- | t -> t
- in
- let rec fo_unif k t1 t2 = match (t1, t2) with
- (* aggiungere l'unificazione sui tipi in caso di istanziazione *)
- (C.Meta n, C.Meta m) -> if n == m then () else
- let t1' = deref n in
- let t2' = deref m in
- (* deref of metavariables ARE already delifted *)
- (match (t1',t2') with
- (C.Meta n, C.Meta m) -> if n = m then () else
- if n < m then mgu.(m) <- t1' else
- if n > m then mgu.(n) <- t2'
- | (C.Meta n, _) -> mgu.(n) <- t2'
- | (_, C.Meta m) -> mgu.(m) <- t1'
- | (_,_) -> fo_unif k t1' t2')
- | (C.Meta n, _) -> let t1' = deref n in
- let t2' = try delift k t2
- with Free -> raise UnificationFailed in
- (match t1' with
- C.Meta n -> mgu.(n) <- t2'
- | _ -> fo_unif k t1' t2')
- | (_, C.Meta m) -> let t2' = deref m in
- let t1' = try delift k t1
- with Free -> raise UnificationFailed in
- (match t2' with
- C.Meta m -> mgu.(m) <- t1'
- | _ -> fo_unif k t1' t2')
- | (C.Rel _, _)
- | (_, C.Rel _)
- | (C.Var _, _)
- | (_, C.Var _)
- | (C.Sort _ ,_)
- | (_, C.Sort _)
- | (C.Implicit, _)
- | (_, C.Implicit) -> if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (C.Cast (te,ty), _) -> fo_unif k te t2
- | (_, C.Cast (te,ty)) -> fo_unif k t1 te
- | (C.Prod (_,s1,t1), C.Prod (_,s2,t2)) -> fo_unif k s1 s2;
- fo_unif (k+1) t1 t2
- | (C.Lambda (_,s1,t1), C.Lambda (_,s2,t2)) -> fo_unif k s1 s2;
- fo_unif (k+1) t1 t2
- | (C.LetIn (_,s1,t1), _) -> fo_unif k (S.subst s1 t1) t2
- | (_, C.LetIn (_,s2,t2)) -> fo_unif k t1 (S.subst s2 t2)
- | (C.Appl (h1::l1), C.Appl (h2::l2)) ->
- let lr1 = List.rev l1 in
- let lr2 = List.rev l2 in
- let rec fo_unif_aux = function
- ([],l2) -> ([],l2)
- | (l1,[]) -> (l1,[])
- | ((h1::l1),(h2::l2)) -> fo_unif k h1 h2;
- fo_unif_aux (l1,l2)
+and fo_unif_subst test_equality_only subst context metasenv t1 t2 ugraph =
+ let module C = Cic in
+ let module R = CicReduction in
+ let module S = CicSubstitution in
+ let t1 = deref subst t1 in
+ let t2 = deref subst t2 in
+ let b,ugraph =
+let foo () =
+ R.are_convertible ~subst ~metasenv context t1 t2 ugraph
+in profiler_are_convertible.HExtlib.profile foo ()
+ in
+ if b then
+ subst, metasenv, ugraph
+ else
+ match (t1, t2) with
+ | (C.Meta (n,ln), C.Meta (m,lm)) when n=m ->
+ let _,subst,metasenv,ugraph1 =
+ (try
+ List.fold_left2
+ (fun (j,subst,metasenv,ugraph) t1 t2 ->
+ match t1,t2 with
+ None,_
+ | _,None -> j+1,subst,metasenv,ugraph
+ | Some t1', Some t2' ->
+ (* First possibility: restriction *)
+ (* Second possibility: unification *)
+ (* Third possibility: convertibility *)
+ let b, ugraph1 =
+ R.are_convertible
+ ~subst ~metasenv context t1' t2' ugraph
in
- (match fo_unif_aux (lr1, lr2) with
- ([],[]) -> fo_unif k h1 h2
- | ([],l2) -> fo_unif k h1 (C.Appl (h2::List.rev l2))
- | (l1,[]) -> fo_unif k (C.Appl (h1::List.rev l1)) h2
- | (_,_) -> raise Impossible)
- | (C.Const _, _)
- | (_, C.Const _)
- | (C.Abst _, _)
- | (_, C.Abst _)
- | (C.MutInd _, _)
- | (_, C.MutInd _)
- | (C.MutConstruct _, _)
- | (_, C.MutConstruct _) -> print_endline "siamo qui"; flush stdout;
- if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (C.MutCase (_,_,_,outt1,t1,pl1), C.MutCase (_,_,_,outt2,t2,pl2))->
- fo_unif k outt1 outt2;
- fo_unif k t1 t2;
- List.iter2 (fo_unif k) pl1 pl2
- | (C.Fix _, _)
- | (_, C.Fix _)
- | (C.CoFix _, _)
- | (_, C.CoFix _) -> if R.are_convertible t1 t2 then ()
- else raise UnificationFailed
- | (_,_) -> raise UnificationFailed
- in fo_unif k t1 t2;mgu ;;
-*)
-
-(* unwind mgu mark m applies mgu to the term m; mark is an array of integers
-mark.(n) = 0 if the term has not been unwinded, is 2 if it is under uwinding,
-and is 1 if it has been succesfully unwinded. Meeting the value 2 during
-the computation is an error: occur-check *)
-
-let unwind subst unwinded t =
- let unwinded = ref unwinded in
- let frozen = ref [] in
- let rec um_aux k =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel _ as t -> t
- | C.Var _ as t -> t
- | C.Meta i as t ->(try S.lift k (List.assoc i !unwinded)
- with Not_found ->
- if List.mem i !frozen then
- raise OccurCheck
+ if b then
+ j+1,subst,metasenv, ugraph1
else
- let saved_frozen = !frozen in
- frozen := i::!frozen ;
- let res =
- try
- let t = List.assoc i subst in
- let t' = um_aux 0 t in
- unwinded := (i,t)::!unwinded ;
- S.lift k t'
- with
- Not_found ->
- (* not constrained variable, i.e. free in subst *)
- C.Meta i
- in
- frozen := saved_frozen ;
- res
- )
- | C.Sort _ as t -> t
- | C.Implicit as t -> t
- | C.Cast (te,ty) -> C.Cast (um_aux k te, um_aux k ty)
- | C.Prod (n,s,t) -> C.Prod (n, um_aux k s, um_aux (k+1) t)
- | C.Lambda (n,s,t) -> C.Lambda (n, um_aux k s, um_aux (k+1) t)
- | C.LetIn (n,s,t) -> C.LetIn (n, um_aux k s, um_aux (k+1) t)
- | C.Appl (he::tl) ->
- let tl' = List.map (um_aux k) tl in
- begin
- match um_aux k he with
- C.Appl l -> C.Appl (l@tl')
- | _ as he' -> C.Appl (he'::tl')
- end
- | C.Appl _ -> assert false
- | C.Const _ as t -> t
- | C.Abst _ as t -> t
- | C.MutInd _ as t -> t
- | C.MutConstruct _ as t -> t
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- C.MutCase (sp, cookingsno, i, um_aux k outty, um_aux k t,
- List.map (um_aux k) pl)
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, i, ty, bo) -> (name, i, um_aux k ty, um_aux (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, um_aux k ty, um_aux (k+len) bo))
- fl
- in
- C.CoFix (i, liftedfl)
- in
- um_aux 0 t,!unwinded
-;;
-
-(*
-let unwind_meta mgu mark =
- let rec um_aux k =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel _ as t -> t
- | C.Var _ as t -> t
- | C.Meta i as t -> if mark.(i)=2 then raise OccurCheck else
- if mark.(i)=1 then S.lift k mgu.(i)
- else (match mgu.(i) with
- C.Meta k as t1 -> if k = i then t
- else (mark.(i) <- 2;
- mgu.(i) <- (um_aux 0 t1);
- mark.(i) <- 1;
- S.lift k mgu.(i))
- | _ -> (mark.(i) <- 2;
- mgu.(i) <- (um_aux 0 mgu.(i));
- mark.(i) <- 1;
- S.lift k mgu.(i)))
- | C.Sort _ as t -> t
- | C.Implicit as t -> t
- | C.Cast (te,ty) -> C.Cast (um_aux k te, um_aux k ty)
- | C.Prod (n,s,t) -> C.Prod (n, um_aux k s, um_aux (k+1) t)
- | C.Lambda (n,s,t) -> C.Lambda (n, um_aux k s, um_aux (k+1) t)
- | C.LetIn (n,s,t) -> C.LetIn (n, um_aux k s, um_aux (k+1) t)
- | C.Appl (he::tl) ->
- let tl' = List.map (um_aux k) tl in
- begin
- match um_aux k he with
- C.Appl l -> C.Appl (l@tl')
- | _ as he' -> C.Appl (he'::tl')
- end
- | C.Appl _ -> assert false
- | C.Const _ as t -> t
- | C.Abst _ as t -> t
- | C.MutInd _ as t -> t
- | C.MutConstruct _ as t -> t
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- C.MutCase (sp, cookingsno, i, um_aux k outty, um_aux k t,
- List.map (um_aux k) pl)
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, i, ty, bo) -> (name, i, um_aux k ty, um_aux (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, um_aux k ty, um_aux (k+len) bo))
- fl
- in
- C.CoFix (i, liftedfl)
- in
- um_aux 0
-;;
-*)
-
-(* apply_subst_reducing subst (Some (mtr,reductions_no)) t *)
-(* performs as (apply_subst subst t) until it finds an application of *)
-(* (META [meta_to_reduce]) that, once unwinding is performed, creates *)
-(* a new beta-redex; in this case up to [reductions_no] consecutive *)
-(* beta-reductions are performed. *)
-(* Hint: this function is usually called when [reductions_no] *)
-(* eta-expansions have been performed and the head of the new *)
-(* application has been unified with (META [meta_to_reduce]): *)
-(* during the unwinding the eta-expansions are undone. *)
-
-let apply_subst_reducing subst meta_to_reduce t =
- let unwinded = ref subst in
- let rec um_aux k =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel _ as t -> t
- | C.Var _ as t -> t
- | C.Meta i as t ->
- (try
- S.lift k (List.assoc i !unwinded)
- with Not_found ->
- C.Meta i)
- | C.Sort _ as t -> t
- | C.Implicit as t -> t
- | C.Cast (te,ty) -> C.Cast (um_aux k te, um_aux k ty)
- | C.Prod (n,s,t) -> C.Prod (n, um_aux k s, um_aux (k+1) t)
- | C.Lambda (n,s,t) -> C.Lambda (n, um_aux k s, um_aux (k+1) t)
- | C.LetIn (n,s,t) -> C.LetIn (n, um_aux k s, um_aux (k+1) t)
- | C.Appl (he::tl) ->
- let tl' = List.map (um_aux k) tl in
- let t' =
- match um_aux k he with
- C.Appl l -> C.Appl (l@tl')
- | _ as he' -> C.Appl (he'::tl')
- in
+ (try
+ let subst,metasenv,ugraph2 =
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv t1' t2' ugraph
+ in
+ j+1,subst,metasenv,ugraph2
+ with
+ Uncertain _
+ | UnificationFailure _ ->
+debug_print (lazy ("restringo Meta n." ^ (string_of_int n) ^ "on variable n." ^ (string_of_int j)));
+ let metasenv, subst =
+ CicMetaSubst.restrict
+ subst [(n,j)] metasenv in
+ j+1,subst,metasenv,ugraph1)
+ ) (1,subst,metasenv,ugraph) ln lm
+ with
+ Exit ->
+ raise
+ (UnificationFailure (lazy "1"))
+ (*
+ (sprintf
+ "Error trying to unify %s with %s: the algorithm tried to check whether the two substitutions are convertible; if they are not, it tried to unify the two substitutions. No restriction was attempted."
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)
+ | Invalid_argument _ ->
+ raise
+ (UnificationFailure (lazy "2")))
+ (*
+ (sprintf
+ "Error trying to unify %s with %s: the lengths of the two local contexts do not match."
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2)))) *)
+ in subst,metasenv,ugraph1
+ | (C.Meta (n,_), C.Meta (m,_)) when n>m ->
+ fo_unif_subst test_equality_only subst context metasenv t2 t1 ugraph
+ | (C.Meta (n,l), t)
+ | (t, C.Meta (n,l)) ->
+ let swap =
+ match t1,t2 with
+ C.Meta (n,_), C.Meta (m,_) when n < m -> false
+ | _, C.Meta _ -> false
+ | _,_ -> true
+ in
+ let lower = fun x y -> if swap then y else x in
+ let upper = fun x y -> if swap then x else y in
+ let fo_unif_subst_ordered
+ test_equality_only subst context metasenv m1 m2 ugraph =
+ fo_unif_subst test_equality_only subst context metasenv
+ (lower m1 m2) (upper m1 m2) ugraph
+ in
begin
- match meta_to_reduce with
- Some (mtr,reductions_no) when he = C.Meta mtr ->
- let rec beta_reduce =
- function
- (n,(C.Appl (C.Lambda (_,_,t)::he'::tl'))) when n > 0 ->
- let he'' = CicSubstitution.subst he' t in
- if tl' = [] then
- he''
- else
- beta_reduce (n-1,C.Appl(he''::tl'))
- | (_,t) -> t
+ let subst,metasenv,ugraph1 =
+ let (_,_,meta_type) = CicUtil.lookup_meta n metasenv in
+ (try
+ let tyt,ugraph1 =
+ type_of_aux' metasenv subst context t ugraph
in
- beta_reduce (reductions_no,t')
- | _ -> t'
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv tyt (S.subst_meta l meta_type) ugraph1
+ with
+ UnificationFailure _ as e -> raise e
+ | Uncertain msg -> raise (UnificationFailure msg)
+ | AssertFailure _ ->
+ debug_print (lazy "siamo allo huge hack");
+ (* TODO huge hack!!!!
+ * we keep on unifying/refining in the hope that
+ * the problem will be eventually solved.
+ * In the meantime we're breaking a big invariant:
+ * the terms that we are unifying are no longer well
+ * typed in the current context (in the worst case
+ * we could even diverge) *)
+ (subst, metasenv,ugraph)) in
+ let t',metasenv,subst =
+ try
+ CicMetaSubst.delift n subst context metasenv l t
+ with
+ (CicMetaSubst.MetaSubstFailure msg)->
+ raise (UnificationFailure msg)
+ | (CicMetaSubst.Uncertain msg) -> raise (Uncertain msg)
+ in
+ let t'',ugraph2 =
+ match t' with
+ C.Sort (C.Type u) when not test_equality_only ->
+ let u' = CicUniv.fresh () in
+ let s = C.Sort (C.Type u') in
+ let ugraph2 =
+ CicUniv.add_ge (upper u u') (lower u u') ugraph1
+ in
+ s,ugraph2
+ | _ -> t',ugraph1
+ in
+ (* Unifying the types may have already instantiated n. Let's check *)
+ try
+ let (_, oldt,_) = CicUtil.lookup_subst n subst in
+ let lifted_oldt = S.subst_meta l oldt in
+ fo_unif_subst_ordered
+ test_equality_only subst context metasenv t lifted_oldt ugraph2
+ with
+ CicUtil.Subst_not_found _ ->
+ let (_, context, ty) = CicUtil.lookup_meta n metasenv in
+ let subst = (n, (context, t'',ty)) :: subst in
+ let metasenv =
+ List.filter (fun (m,_,_) -> not (n = m)) metasenv in
+ subst, metasenv, ugraph2
end
- | C.Appl _ -> assert false
- | C.Const _ as t -> t
- | C.Abst _ as t -> t
- | C.MutInd _ as t -> t
- | C.MutConstruct _ as t -> t
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- C.MutCase (sp, cookingsno, i, um_aux k outty, um_aux k t,
- List.map (um_aux k) pl)
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, i, ty, bo) -> (name, i, um_aux k ty, um_aux (k+len) bo))
- fl
+ | (C.Var (uri1,exp_named_subst1),C.Var (uri2,exp_named_subst2))
+ | (C.Const (uri1,exp_named_subst1),C.Const (uri2,exp_named_subst2)) ->
+ if UriManager.eq uri1 uri2 then
+ fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
+ exp_named_subst1 exp_named_subst2 ugraph
+ else
+ raise (UnificationFailure (lazy
+ (sprintf
+ "Can't unify %s with %s due to different constants"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))))
+ | C.MutInd (uri1,i1,exp_named_subst1),C.MutInd (uri2,i2,exp_named_subst2) ->
+ if UriManager.eq uri1 uri2 && i1 = i2 then
+ fo_unif_subst_exp_named_subst
+ test_equality_only
+ subst context metasenv exp_named_subst1 exp_named_subst2 ugraph
+ else
+ raise (UnificationFailure (lazy "4"))
+ (* (sprintf
+ "Can't unify %s with %s due to different inductive principles"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)
+ | C.MutConstruct (uri1,i1,j1,exp_named_subst1),
+ C.MutConstruct (uri2,i2,j2,exp_named_subst2) ->
+ if UriManager.eq uri1 uri2 && i1 = i2 && j1 = j2 then
+ fo_unif_subst_exp_named_subst
+ test_equality_only
+ subst context metasenv exp_named_subst1 exp_named_subst2 ugraph
+ else
+ raise (UnificationFailure (lazy "5"))
+ (* (sprintf
+ "Can't unify %s with %s due to different inductive constructors"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)
+ | (C.Implicit _, _) | (_, C.Implicit _) -> assert false
+ | (C.Cast (te,ty), t2) -> fo_unif_subst test_equality_only
+ subst context metasenv te t2 ugraph
+ | (t1, C.Cast (te,ty)) -> fo_unif_subst test_equality_only
+ subst context metasenv t1 te ugraph
+ | (C.Prod (n1,s1,t1), C.Prod (_,s2,t2)) ->
+ let subst',metasenv',ugraph1 =
+ fo_unif_subst true subst context metasenv s1 s2 ugraph
in
- C.Fix (i, liftedfl)
- | C.CoFix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, ty, bo) -> (name, um_aux k ty, um_aux (k+len) bo))
- fl
+ fo_unif_subst test_equality_only
+ subst' ((Some (n1,(C.Decl s1)))::context) metasenv' t1 t2 ugraph1
+ | (C.Lambda (n1,s1,t1), C.Lambda (_,s2,t2)) ->
+ let subst',metasenv',ugraph1 =
+ fo_unif_subst test_equality_only subst context metasenv s1 s2 ugraph
in
- C.CoFix (i, liftedfl)
- in
- um_aux 0 t
-;;
-
-(* unwind mgu mark mm m applies mgu to the term m; mark is an array of integers
-mark.(n) = 0 if the term has not been unwinded, is 2 if it is under uwinding,
-and is 1 if it has been succesfully unwinded. Meeting the value 2 during
-the computation is an error: occur-check. When the META mm is to be unfolded
-and it is applied to something, one-step beta reduction is performed just
-after the unfolding. *)
-
-(*
-let unwind_meta_reducing mgu mark meta_to_reduce =
- let rec um_aux k =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel _ as t -> t
- | C.Var _ as t -> t
- | C.Meta i as t -> if mark.(i)=2 then raise OccurCheck else
- if mark.(i)=1 then S.lift k mgu.(i)
- else (match mgu.(i) with
- C.Meta k as t1 -> if k = i then t
- else (mark.(i) <- 2;
- mgu.(i) <- (um_aux 0 t1);
- mark.(i) <- 1;
- S.lift k mgu.(i))
- | _ -> (mark.(i) <- 2;
- mgu.(i) <- (um_aux 0 mgu.(i));
- mark.(i) <- 1;
- S.lift k mgu.(i)))
- | C.Sort _ as t -> t
- | C.Implicit as t -> t
- | C.Cast (te,ty) -> C.Cast (um_aux k te, um_aux k ty)
- | C.Prod (n,s,t) -> C.Prod (n, um_aux k s, um_aux (k+1) t)
- | C.Lambda (n,s,t) -> C.Lambda (n, um_aux k s, um_aux (k+1) t)
- | C.LetIn (n,s,t) -> C.LetIn (n, um_aux k s, um_aux (k+1) t)
- | C.Appl (he::tl) ->
- let tl' = List.map (um_aux k) tl in
- let t' =
- match um_aux k he with
- C.Appl l -> C.Appl (l@tl')
- | _ as he' -> C.Appl (he'::tl')
- in
- begin
- match t', meta_to_reduce with
- (C.Appl (C.Lambda (n,s,t)::he'::tl')),Some mtr
- when he = C.Meta mtr ->
-(*CSC: Sbagliato!!! Effettua beta riduzione solo del primo argomento
- *CSC: mentre dovrebbe farla dei primi n, dove n sono quelli eta-astratti
-*)
- C.Appl((CicSubstitution.subst he' t)::tl')
- | _ -> t'
- end
- | C.Appl _ -> assert false
- | C.Const _ as t -> t
- | C.Abst _ as t -> t
- | C.MutInd _ as t -> t
- | C.MutConstruct _ as t -> t
- | C.MutCase (sp,cookingsno,i,outty,t,pl) ->
- C.MutCase (sp, cookingsno, i, um_aux k outty, um_aux k t,
- List.map (um_aux k) pl)
- | C.Fix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, i, ty, bo) -> (name, i, um_aux k ty, um_aux (k+len) bo))
- fl
+ fo_unif_subst test_equality_only
+ subst' ((Some (n1,(C.Decl s1)))::context) metasenv' t1 t2 ugraph1
+ | (C.LetIn (_,s1,t1), t2)
+ | (t2, C.LetIn (_,s1,t1)) ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t2 (S.subst s1 t1) ugraph
+ | (C.Appl l1, C.Appl l2) ->
+ (* andrea: this case should be probably rewritten in the
+ spirit of deref *)
+ (match l1,l2 with
+ | C.Meta (i,_)::args1, C.Meta (j,_)::args2 when i = j ->
+ (try
+ List.fold_left2
+ (fun (subst,metasenv,ugraph) t1 t2 ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t1 t2 ugraph)
+ (subst,metasenv,ugraph) l1 l2
+ with (Invalid_argument msg) ->
+ raise (UnificationFailure (lazy msg)))
+ | C.Meta (i,l)::args, _ when not(exists_a_meta args) ->
+ (* we verify that none of the args is a Meta,
+ since beta expanding with respoect to a metavariable
+ makes no sense *)
+ (*
+ (try
+ let (_,t,_) = CicUtil.lookup_subst i subst in
+ let lifted = S.subst_meta l t in
+ let reduced = CicReduction.head_beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv reduced t2 ugraph
+ with CicUtil.Subst_not_found _ -> *)
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only metasenv subst context t2 args ugraph
+ in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded ugraph1
+ | _, C.Meta (i,l)::args when not(exists_a_meta args) ->
+ (* (try
+ let (_,t,_) = CicUtil.lookup_subst i subst in
+ let lifted = S.subst_meta l t in
+ let reduced = CicReduction.head_beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv t1 reduced ugraph
+ with CicUtil.Subst_not_found _ -> *)
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only
+ metasenv subst context t1 args ugraph
+ in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded ugraph1
+ | _,_ ->
+ let lr1 = List.rev l1 in
+ let lr2 = List.rev l2 in
+ let rec
+ fo_unif_l test_equality_only subst metasenv (l1,l2) ugraph =
+ match (l1,l2) with
+ [],_
+ | _,[] -> assert false
+ | ([h1],[h2]) ->
+ fo_unif_subst
+ test_equality_only subst context metasenv h1 h2 ugraph
+ | ([h],l)
+ | (l,[h]) ->
+ fo_unif_subst test_equality_only subst context metasenv
+ h (C.Appl (List.rev l)) ugraph
+ | ((h1::l1),(h2::l2)) ->
+ let subst', metasenv',ugraph1 =
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv h1 h2 ugraph
+ in
+ fo_unif_l
+ test_equality_only subst' metasenv' (l1,l2) ugraph1
+ in
+ fo_unif_l
+ test_equality_only subst metasenv (lr1, lr2) ugraph)
+ | (C.MutCase (_,_,outt1,t1',pl1), C.MutCase (_,_,outt2,t2',pl2))->
+ let subst', metasenv',ugraph1 =
+ fo_unif_subst test_equality_only subst context metasenv outt1 outt2
+ ugraph in
+ let subst'',metasenv'',ugraph2 =
+ fo_unif_subst test_equality_only subst' context metasenv' t1' t2'
+ ugraph1 in
+ (try
+ List.fold_left2
+ (fun (subst,metasenv,ugraph) t1 t2 ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t1 t2 ugraph
+ ) (subst'',metasenv'',ugraph2) pl1 pl2
+ with
+ Invalid_argument _ ->
+ raise (UnificationFailure (lazy "6.1")))
+ (* (sprintf
+ "Error trying to unify %s with %s: the number of branches is not the same."
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2)))) *)
+ | (C.Rel _, _) | (_, C.Rel _) ->
+ if t1 = t2 then
+ subst, metasenv,ugraph
+ else
+ raise (UnificationFailure (lazy
+ (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))))
+ | (C.Appl (C.Meta(i,l)::args),t2) when not(exists_a_meta args) ->
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only metasenv subst context t2 args ugraph
in
- C.Fix (i, liftedfl)
- | C.CoFix (i, fl) ->
- let len = List.length fl in
- let liftedfl =
- List.map
- (fun (name, ty, bo) -> (name, um_aux k ty, um_aux (k+len) bo))
- fl
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded ugraph1
+ | (t1,C.Appl (C.Meta(i,l)::args)) when not(exists_a_meta args) ->
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only metasenv subst context t1 args ugraph
in
- C.CoFix (i, liftedfl)
- in
- um_aux 0
-;; *)
+ fo_unif_subst test_equality_only subst context metasenv
+ beta_expanded (C.Meta (i,l)) ugraph1
+ | (C.Sort _ ,_) | (_, C.Sort _)
+ | (C.Const _, _) | (_, C.Const _)
+ | (C.MutInd _, _) | (_, C.MutInd _)
+ | (C.MutConstruct _, _) | (_, C.MutConstruct _)
+ | (C.Fix _, _) | (_, C.Fix _)
+ | (C.CoFix _, _) | (_, C.CoFix _) ->
+ if t1 = t2 then
+ subst, metasenv, ugraph
+ else
+ let b,ugraph1 =
+ R.are_convertible ~subst ~metasenv context t1 t2 ugraph
+ in
+ if b then
+ subst, metasenv, ugraph1
+ else
+ raise
+ (UnificationFailure (lazy (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))))
+ | (C.Prod _, t2) ->
+ let t2' = R.whd ~subst context t2 in
+ (match t2' with
+ C.Prod _ ->
+ fo_unif_subst test_equality_only
+ subst context metasenv t1 t2' ugraph
+ | _ -> raise (UnificationFailure (lazy "8")))
+ | (t1, C.Prod _) ->
+ let t1' = R.whd ~subst context t1 in
+ (match t1' with
+ C.Prod _ ->
+ fo_unif_subst test_equality_only
+ subst context metasenv t1' t2 ugraph
+ | _ -> (* raise (UnificationFailure "9")) *)
+ raise
+ (UnificationFailure (lazy (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2)))))
+ | (_,_) ->
+ raise (UnificationFailure (lazy "10"))
+ (* (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)
-(* UNWIND THE MGU INSIDE THE MGU *)
-(* let unwind mgu =
- let mark = Array.make (Array.length mgu) 0 in
- Array.iter (fun x -> let foo = unwind_meta mgu mark x in ()) mgu; mgu;; *)
+and fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
+ exp_named_subst1 exp_named_subst2 ugraph
+=
+ try
+ List.fold_left2
+ (fun (subst,metasenv,ugraph) (uri1,t1) (uri2,t2) ->
+ assert (uri1=uri2) ;
+ fo_unif_subst test_equality_only subst context metasenv t1 t2 ugraph
+ ) (subst,metasenv,ugraph) exp_named_subst1 exp_named_subst2
+ with
+ Invalid_argument _ ->
+ let print_ens ens =
+ String.concat " ; "
+ (List.map
+ (fun (uri,t) ->
+ UriManager.string_of_uri uri ^ " := " ^ (CicMetaSubst.ppterm subst t)
+ ) ens)
+ in
+ raise (UnificationFailure (lazy (sprintf
+ "Error trying to unify the two explicit named substitutions (local contexts) %s and %s: their lengths is different." (print_ens exp_named_subst1) (print_ens exp_named_subst2))))
-let unwind_subst subst =
- List.fold_left
- (fun unwinded (i,_) -> snd (unwind subst unwinded (Cic.Meta i))) [] subst
-;;
+(* A substitution is a (int * Cic.term) list that associates a *)
+(* metavariable i with its body. *)
+(* metasenv is of type Cic.metasenv *)
+(* fo_unif takes a metasenv, a context, two terms t1 and t2 and gives back *)
+(* a new substitution which is already unwinded and ready to be applied and *)
+(* a new metasenv in which some hypothesis in the contexts of the *)
+(* metavariables may have been restricted. *)
+let fo_unif metasenv context t1 t2 ugraph =
+ fo_unif_subst false [] context metasenv t1 t2 ugraph ;;
-let apply_subst subst t =
- fst (unwind [] subst t)
-;;
+let enrich_msg msg subst context metasenv t1 t2 ugraph =
+ lazy (
+ if verbose then
+ sprintf "[Verbose] Unification error unifying %s of type %s with %s of type %s in context\n%s\nand metasenv\n%s\nand substitution\n%s\nbecause %s"
+ (CicMetaSubst.ppterm subst t1)
+ (try
+ let ty_t1,_ = type_of_aux' metasenv subst context t1 ugraph in
+ CicPp.ppterm ty_t1
+ with
+ | UnificationFailure s
+ | Uncertain s
+ | AssertFailure s -> sprintf "MALFORMED(t1): \n<BEGIN>%s\n<END>" (Lazy.force s))
+ (CicMetaSubst.ppterm subst t2)
+ (try
+ let ty_t2,_ = type_of_aux' metasenv subst context t2 ugraph in
+ CicPp.ppterm ty_t2
+ with
+ | UnificationFailure s
+ | Uncertain s
+ | AssertFailure s -> sprintf "MALFORMED(t2): \n<BEGIN>%s\n<END>" (Lazy.force s))
+ (CicMetaSubst.ppcontext subst context)
+ (CicMetaSubst.ppmetasenv subst metasenv)
+ (CicMetaSubst.ppsubst subst) (Lazy.force msg)
+ else
+ sprintf "Unification error unifying %s of type %s with %s of type %s in context\n%s\nand metasenv\n%s\nbecause %s"
+ (CicMetaSubst.ppterm_in_context subst t1 context)
+ (try
+ let ty_t1,_ = type_of_aux' metasenv subst context t1 ugraph in
+ CicMetaSubst.ppterm_in_context subst ty_t1 context
+ with
+ | UnificationFailure s
+ | Uncertain s
+ | AssertFailure s -> sprintf "MALFORMED(t1): \n<BEGIN>%s\n<END>" (Lazy.force s))
+ (CicMetaSubst.ppterm_in_context subst t2 context)
+ (try
+ let ty_t2,_ = type_of_aux' metasenv subst context t2 ugraph in
+ CicMetaSubst.ppterm_in_context subst ty_t2 context
+ with
+ | UnificationFailure s
+ | Uncertain s
+ | AssertFailure s -> sprintf "MALFORMED(t2): \n<BEGIN>%s\n<END>" (Lazy.force s))
+ (CicMetaSubst.ppcontext subst context)
+ (CicMetaSubst.ppmetasenv subst metasenv)
+ (Lazy.force msg)
+ )
-(* A substitution is a (int * Cic.term) list that associates a
- metavariable i with its body.
- A metaenv is a (int * Cic.term) list that associate a metavariable
- i with is type.
- fo_unif takes a metasenv, a context,
- two terms t1 and t2 and gives back a new
- substitution which is already unwinded and ready to be applied. *)
-let fo_unif metasenv context t1 t2 =
- let subst_to_unwind = fo_unif_new metasenv context t1 t2 in
- unwind_subst subst_to_unwind
+let fo_unif_subst subst context metasenv t1 t2 ugraph =
+ try
+ fo_unif_subst false subst context metasenv t1 t2 ugraph
+ with
+ | AssertFailure msg ->
+ raise (AssertFailure (enrich_msg msg subst context metasenv t1 t2 ugraph))
+ | UnificationFailure msg ->
+ raise (UnificationFailure (enrich_msg msg subst context metasenv t1 t2 ugraph))
;;
projects / helm.git / blobdiff