X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Fcic_unification%2FcicRefine.ml;h=5c031f4733b6806f2da7c1b9ef683d8d589112ec;hb=91a095f0686ee569ba035e4e30c7d071588cb8e7;hp=38e822c33cd468f5169fad859ea7b43caeed29aa;hpb=e98de6c5ff6d10baefd2d7492a8fdcd0a3fa1a6c;p=helm.git diff --git a/helm/ocaml/cic_unification/cicRefine.ml b/helm/ocaml/cic_unification/cicRefine.ml index 38e822c33..5c031f473 100644 --- a/helm/ocaml/cic_unification/cicRefine.ml +++ b/helm/ocaml/cic_unification/cicRefine.ml @@ -29,7 +29,7 @@ exception RefineFailure of string;; exception Uncertain of string;; exception AssertFailure of string;; -let debug_print = prerr_endline +let debug_print = fun _ -> () let fo_unif_subst subst context metasenv t1 t2 ugraph = try @@ -46,23 +46,6 @@ let rec split l n = | (_,_) -> raise (AssertFailure "split: list too short") ;; -let look_for_coercion src tgt = - if (src = (CicUtil.term_of_uri "cic:/Coq/Init/Datatypes/nat.ind#xpointer(1/1)")) && - (tgt = (CicUtil.term_of_uri "cic:/Coq/Reals/Rdefinitions/R.con")) - then - begin - prerr_endline "TROVATA coercion"; - Some (CicUtil.term_of_uri "cic:/Coq/Reals/Raxioms/INR.con") - end - else - begin - prerr_endline (sprintf "NON TROVATA la coercion %s %s" (CicPp.ppterm src) - (CicPp.ppterm tgt)); - None - end -;; - - let rec type_of_constant uri ugraph = let module C = Cic in let module R = CicReduction in @@ -224,17 +207,17 @@ and type_of_aux' metasenv context t ugraph = canonical_context l ugraph in (* trust or check ??? *) - C.Meta (n,l'),CicSubstitution.lift_meta l' ty, + C.Meta (n,l'),CicSubstitution.subst_meta l' ty, subst', metasenv', ugraph1 (* type_of_aux subst metasenv - context (CicSubstitution.lift_meta l term) *) + context (CicSubstitution.subst_meta l term) *) with CicUtil.Subst_not_found _ -> let (_,canonical_context,ty) = CicUtil.lookup_meta n metasenv in let l',subst',metasenv', ugraph1 = check_metasenv_consistency n subst metasenv context canonical_context l ugraph in - C.Meta (n,l'),CicSubstitution.lift_meta l' ty, + C.Meta (n,l'),CicSubstitution.subst_meta l' ty, subst', metasenv',ugraph1) | C.Sort (C.Type tno) -> let tno' = CicUniv.fresh() in @@ -253,7 +236,7 @@ and type_of_aux' metasenv context t ugraph = (try let subst''',metasenv''',ugraph3 = fo_unif_subst subst'' context metasenv'' - inferredty ty' ugraph2 + inferredty ty ugraph2 in C.Cast (te',ty'),ty',subst''',metasenv''',ugraph3 with @@ -304,7 +287,7 @@ and type_of_aux' metasenv context t ugraph = * Moreover the inferred type is closer to the expected one. *) C.LetIn (n,s',t'),CicSubstitution.subst s' inferredty, - subst',metasenv',ugraph2 + subst'',metasenv'',ugraph2 | C.Appl (he::((_::_) as tl)) -> let he',hetype,subst',metasenv',ugraph1 = type_of_aux subst metasenv context he ugraph @@ -405,6 +388,17 @@ and type_of_aux' metasenv context t ugraph = fo_unif_subst subst context metasenv expected_type' actual_type ugraph2 in + let rec instantiate_prod t = + function + [] -> t + | he::tl -> + match CicReduction.whd ~subst context t with + C.Prod (_,_,t') -> + instantiate_prod (CicSubstitution.subst he t') tl + | _ -> assert false + in + let arity_instantiated_with_left_args = + instantiate_prod arity left_args in (* TODO: check if the sort elimination * is allowed: [(I q1 ... qr)|B] *) let (pl',_,outtypeinstances,subst,metasenv,ugraph4) = @@ -440,49 +434,135 @@ and type_of_aux' metasenv context t ugraph = (match outtype with | C.Meta (n,l) -> - (let candidate,ugraph5 = + (let candidate,ugraph5,metasenv,subst = + let exp_name_subst, metasenv = + let o,_ = + CicEnvironment.get_obj CicUniv.empty_ugraph uri + in + let uris = CicUtil.params_of_obj o in + List.fold_right ( + fun uri (acc,metasenv) -> + let metasenv',new_meta = + CicMkImplicit.mk_implicit metasenv subst context + in + let irl = + CicMkImplicit.identity_relocation_list_for_metavariable + context + in + (uri, Cic.Meta(new_meta,irl))::acc, metasenv' + ) uris ([],metasenv) + in + let ty = + match left_args,right_args with + [],[] -> Cic.MutInd(uri, i, exp_name_subst) + | _,_ -> + let rec mk_right_args = + function + 0 -> [] + | n -> (Cic.Rel n)::(mk_right_args (n - 1)) + in + let right_args_no = List.length right_args in + let lifted_left_args = + List.map (CicSubstitution.lift right_args_no) left_args + in + Cic.Appl (Cic.MutInd(uri,i,exp_name_subst):: + (lifted_left_args @ mk_right_args right_args_no)) + in + let fresh_name = + FreshNamesGenerator.mk_fresh_name ~subst metasenv + context Cic.Anonymous ~typ:ty + in match outtypeinstances with - | [] -> raise (Uncertain "Inference of annotation for empty inductive types not implemented") + | [] -> + let extended_context = + let rec add_right_args = + function + Cic.Prod (name,ty,t) -> + Some (name,Cic.Decl ty)::(add_right_args t) + | _ -> [] + in + (Some (fresh_name,Cic.Decl ty)):: + (List.rev + (add_right_args arity_instantiated_with_left_args))@ + context + in + let metasenv,new_meta = + CicMkImplicit.mk_implicit metasenv subst extended_context + in + let irl = + CicMkImplicit.identity_relocation_list_for_metavariable + extended_context + in + let rec add_lambdas b = + function + Cic.Prod (name,ty,t) -> + Cic.Lambda (name,ty,(add_lambdas b t)) + | _ -> Cic.Lambda (fresh_name, ty, b) + in + let candidate = + add_lambdas (Cic.Meta (new_meta,irl)) + arity_instantiated_with_left_args + in + (Some candidate),ugraph4,metasenv,subst | (constructor_args_no,_,instance,_)::tl -> try - let instance' = - CicSubstitution.delift constructor_args_no - (CicMetaSubst.apply_subst subst instance) + let instance',subst,metasenv = + CicMetaSubst.delift_rels subst metasenv + constructor_args_no instance in + let candidate,ugraph,metasenv,subst = List.fold_left ( - fun (candidate_oty,ugraph) + fun (candidate_oty,ugraph,metasenv,subst) (constructor_args_no,_,instance,_) -> match candidate_oty with - | None -> None,ugraph + | None -> None,ugraph,metasenv,subst | Some ty -> try - let instance' = - CicSubstitution.delift - constructor_args_no - (CicMetaSubst.apply_subst subst instance) + let instance',subst,metasenv = + CicMetaSubst.delift_rels subst metasenv + constructor_args_no instance in - let b,ugraph1 = - CicReduction.are_convertible context - instance' ty ugraph + let subst,metasenv,ugraph = + fo_unif_subst subst context metasenv + instance' ty ugraph in - if b then - candidate_oty,ugraph1 - else - None,ugraph - with Failure s -> None,ugraph - ) (Some instance',ugraph4) tl - with Failure s -> - None,ugraph4 + candidate_oty,ugraph,metasenv,subst + with + CicMetaSubst.DeliftingARelWouldCaptureAFreeVariable + | CicUnification.UnificationFailure _ + | CicUnification.Uncertain _ -> + None,ugraph,metasenv,subst + ) (Some instance',ugraph4,metasenv,subst) tl + in + match candidate with + | None -> None, ugraph,metasenv,subst + | Some t -> + let rec add_lambdas n b = + function + Cic.Prod (name,ty,t) -> + Cic.Lambda (name,ty,(add_lambdas (n + 1) b t)) + | _ -> + Cic.Lambda (fresh_name, ty, + CicSubstitution.lift (n + 1) t) + in + Some + (add_lambdas 0 t arity_instantiated_with_left_args), + ugraph,metasenv,subst + with CicMetaSubst.DeliftingARelWouldCaptureAFreeVariable -> + None,ugraph4,metasenv,subst in match candidate with | None -> raise (Uncertain "can't solve an higher order unification problem") | Some candidate -> - prerr_endline ("CANDIDATE=" ^ (CicPp.ppterm candidate)); - let s,m,u = + let subst,metasenv,ugraph = fo_unif_subst subst context metasenv candidate outtype ugraph5 in - C.MutCase (uri, i, outtype, term', pl'),candidate,s,m,u) + C.MutCase (uri, i, outtype, term', pl'), + CicReduction.head_beta_reduce + (CicMetaSubst.apply_subst subst + (Cic.Appl (outtype::right_args@[term']))), + subst,metasenv,ugraph) | _ -> (* easy case *) let _,_, subst, metasenv,ugraph5 = type_of_aux subst metasenv context @@ -506,8 +586,9 @@ and type_of_aux' metasenv context t ugraph = (subst,metasenv,ugraph5) outtypeinstances in C.MutCase (uri, i, outtype, term', pl'), - CicReduction.whd ~subst context - (C.Appl(outtype::right_args@[term])), + CicReduction.head_beta_reduce + (CicMetaSubst.apply_subst subst + (C.Appl(outtype::right_args@[term]))), subst,metasenv,ugraph6) | C.Fix (i,fl) -> let fl_ty',subst,metasenv,types,ugraph1 = @@ -606,14 +687,14 @@ and type_of_aux' metasenv context t ugraph = function [] -> [] | (Some (n,C.Decl t))::tl -> - (Some (n,C.Decl (S.lift_meta l (S.lift i t))))::(aux (i+1) tl) + (Some (n,C.Decl (S.subst_meta l (S.lift i t))))::(aux (i+1) tl) | (Some (n,C.Def (t,None)))::tl -> - (Some (n,C.Def ((S.lift_meta l (S.lift i t)),None)))::(aux (i+1) tl) + (Some (n,C.Def ((S.subst_meta l (S.lift i t)),None)))::(aux (i+1) tl) | None::tl -> None::(aux (i+1) tl) | (Some (n,C.Def (t,Some ty)))::tl -> (Some (n, - C.Def ((S.lift_meta l (S.lift i t)), - Some (S.lift_meta l (S.lift i ty))))) :: (aux (i+1) tl) + C.Def ((S.subst_meta l (S.lift i t)), + Some (S.subst_meta l (S.lift i ty))))) :: (aux (i+1) tl) in aux 1 canonical_context in @@ -785,7 +866,7 @@ and type_of_aux' metasenv context t ugraph = try fo_unif_subst subst context metasenv hetype hetype' ugraph with exn -> - prerr_endline (Printf.sprintf "hetype=%s\nhetype'=%s\nmetasenv=%s\nsubst=%s" + debug_print (Printf.sprintf "hetype=%s\nhetype'=%s\nmetasenv=%s\nsubst=%s" (CicPp.ppterm hetype) (CicPp.ppterm hetype') (CicMetaSubst.ppmetasenv metasenv []) @@ -807,7 +888,7 @@ and type_of_aux' metasenv context t ugraph = hete,subst,metasenv,ugraph1 with exn -> (* we search a coercion from hety to s *) - let coer = look_for_coercion + let coer = CoercGraph.look_for_coercion (CicMetaSubst.apply_subst subst hety) (CicMetaSubst.apply_subst subst s) in @@ -878,6 +959,105 @@ and type_of_aux' metasenv context t ugraph = (cleaned_t,cleaned_ty,cleaned_metasenv,ugraph1) ;; +let type_of_aux' metasenv context term ugraph = + try + type_of_aux' metasenv context term ugraph + with + CicUniv.UniverseInconsistency msg -> raise (RefineFailure msg) + +(*CSC: this is a very very rough approximation; to be finished *) +let are_all_occurrences_positive uri = + let rec aux = + (*CSC: here we should do a whd; but can we do that? *) + function + Cic.Appl (Cic.MutInd (uri',_,_)::_) when uri = uri' -> () + | Cic.MutInd (uri',_,_) when uri = uri' -> () + | Cic.Prod (_,_,t) -> aux t + | _ -> raise (RefineFailure "not well formed constructor type") + in + aux + +let typecheck metasenv uri obj = + let ugraph = CicUniv.empty_ugraph in + match obj with + Cic.Constant (name,Some bo,ty,args,attrs) -> + let bo',boty,metasenv,ugraph = type_of_aux' metasenv [] bo ugraph in + let ty',_,metasenv,ugraph = type_of_aux' metasenv [] ty ugraph in + let subst,metasenv,ugraph = fo_unif_subst [] [] metasenv boty ty' ugraph in + let bo' = CicMetaSubst.apply_subst subst bo' in + let ty' = CicMetaSubst.apply_subst subst ty' in + let metasenv = CicMetaSubst.apply_subst_metasenv subst metasenv in + Cic.Constant (name,Some bo',ty',args,attrs),metasenv,ugraph + | Cic.Constant (name,None,ty,args,attrs) -> + let ty',_,metasenv,ugraph = type_of_aux' metasenv [] ty ugraph in + Cic.Constant (name,None,ty',args,attrs),metasenv,ugraph + | Cic.CurrentProof (name,metasenv',bo,ty,args,attrs) -> + assert (metasenv' = metasenv); + (* Here we do not check the metasenv for correctness *) + let bo',boty,metasenv,ugraph = type_of_aux' metasenv [] bo ugraph in + let ty',sort,metasenv,ugraph = type_of_aux' metasenv [] ty ugraph in + begin + match sort with + Cic.Sort _ + (* instead of raising Uncertain, let's hope that the meta will become + a sort *) + | Cic.Meta _ -> () + | _ -> raise (RefineFailure "The term provided is not a type") + end; + let subst,metasenv,ugraph = fo_unif_subst [] [] metasenv boty ty' ugraph in + let bo' = CicMetaSubst.apply_subst subst bo' in + let ty' = CicMetaSubst.apply_subst subst ty' in + let metasenv = CicMetaSubst.apply_subst_metasenv subst metasenv in + Cic.CurrentProof (name,metasenv,bo',ty',args,attrs),metasenv,ugraph + | Cic.Variable _ -> assert false (* not implemented *) + | Cic.InductiveDefinition (tys,args,paramsno,attrs) -> + (*CSC: this code is greately simplified and many many checks are missing *) + (*CSC: e.g. the constructors are not required to build their own types, *) + (*CSC: the arities are not required to have as type a sort, etc. *) + let uri = match uri with Some uri -> uri | None -> assert false in + let typesno = List.length tys in + (* first phase: we fix only the types *) + let metasenv,ugraph,tys = + List.fold_right + (fun (name,b,ty,cl) (metasenv,ugraph,res) -> + let ty',_,metasenv,ugraph = type_of_aux' metasenv [] ty ugraph in + metasenv,ugraph,(name,b,ty',cl)::res + ) tys (metasenv,ugraph,[]) in + let con_context = + List.rev_map (fun (name,_,ty,_)-> Some (Cic.Name name,Cic.Decl ty)) tys in + (* second phase: we fix only the constructors *) + let metasenv,ugraph,tys = + List.fold_right + (fun (name,b,ty,cl) (metasenv,ugraph,res) -> + let metasenv,ugraph,cl' = + List.fold_right + (fun (name,ty) (metasenv,ugraph,res) -> + let ty = CicTypeChecker.debrujin_constructor uri typesno ty in + let ty',_,metasenv,ugraph = + type_of_aux' metasenv con_context ty ugraph in + let undebrujin t = + snd + (List.fold_right + (fun (name,_,_,_) (i,t) -> + (* here the explicit_named_substituion is assumed to be *) + (* of length 0 *) + let t' = Cic.MutInd (uri,i,[]) in + let t = CicSubstitution.subst t' t in + i - 1,t + ) tys (typesno - 1,t)) in + let ty' = undebrujin ty' in + metasenv,ugraph,(name,ty')::res + ) cl (metasenv,ugraph,[]) + in + metasenv,ugraph,(name,b,ty,cl')::res + ) tys (metasenv,ugraph,[]) in + (* third phase: we check the positivity condition *) + List.iter + (fun (_,_,_,cl) -> + List.iter (fun (_,ty) -> are_all_occurrences_positive uri ty) cl + ) tys ; + Cic.InductiveDefinition (tys,args,paramsno,attrs),metasenv,ugraph + (* DEBUGGING ONLY let type_of_aux' metasenv context term = try