+ match CicReduction.whd ~subst:subst' context sort1 with
+ | C.Meta _ | C.Sort _ -> s',sort1, subst', metasenv', ugraph1
+ | coercion_src ->
+ let coercion_tgt = Cic.Sort (Cic.Type (CicUniv.fresh())) in
+ let search = CoercGraph.look_for_coercion in
+ let boh = search coercion_src coercion_tgt in
+ match boh with
+ | CoercGraph.SomeCoercion c ->
+ let newt, tty, subst', metasenv', ugraph1 =
+ avoid_double_coercion
+ subst' metasenv' ugraph1
+ (Cic.Appl[c;s']) coercion_tgt
+ in
+ newt, tty, subst', metasenv', ugraph1
+ | CoercGraph.NoCoercion
+ | CoercGraph.NotHandled _ ->
+ enrich localization_tbl s'
+ (RefineFailure
+ (lazy ("The term " ^
+ CicMetaSubst.ppterm_in_context subst s' context ^
+ " is not a type since it has type " ^
+ CicMetaSubst.ppterm_in_context
+ subst coercion_src context ^ " that is not a sort")))
+ | CoercGraph.NotMetaClosed ->
+ enrich localization_tbl s'
+ (Uncertain
+ (lazy ("The term " ^
+ CicMetaSubst.ppterm_in_context subst s' context ^
+ " is not a type since it has type " ^
+ CicMetaSubst.ppterm_in_context
+ subst coercion_src context ^ " that is not a sort")))
+ in
+ let context_for_t = ((Some (n,(C.Decl s')))::context) in
+ let t',type2,subst'',metasenv'',ugraph2 =
+ type_of_aux subst' metasenv' context_for_t t ugraph1
+ in
+ C.Lambda (n,s',t'),C.Prod (n,s',type2),
+ subst'',metasenv'',ugraph2
+ | C.LetIn (n,s,t) ->
+ (* only to check if s is well-typed *)
+ let s',ty,subst',metasenv',ugraph1 =
+ type_of_aux subst metasenv context s ugraph
+ in
+ let context_for_t = ((Some (n,(C.Def (s',Some ty))))::context) in
+
+ let t',inferredty,subst'',metasenv'',ugraph2 =
+ type_of_aux subst' metasenv'
+ context_for_t t ugraph1
+ in
+ (* One-step LetIn reduction.
+ * Even faster than the previous solution.
+ * Moreover the inferred type is closer to the expected one.
+ *)
+ C.LetIn (n,s',t'),CicSubstitution.subst s' inferredty,
+ subst'',metasenv'',ugraph2
+ | C.Appl (he::((_::_) as tl)) ->
+ let he',hetype,subst',metasenv',ugraph1 =
+ type_of_aux subst metasenv context he ugraph
+ in
+ let tlbody_and_type,subst'',metasenv'',ugraph2 =
+ List.fold_right
+ (fun x (res,subst,metasenv,ugraph) ->
+ let x',ty,subst',metasenv',ugraph1 =
+ type_of_aux subst metasenv context x ugraph
+ in
+ (x', ty)::res,subst',metasenv',ugraph1
+ ) tl ([],subst',metasenv',ugraph1)
+ in
+ let tl',applty,subst''',metasenv''',ugraph3 =
+ eat_prods true subst'' metasenv'' context
+ hetype tlbody_and_type ugraph2
+ in
+ avoid_double_coercion
+ subst''' metasenv''' ugraph3 (C.Appl (he'::tl')) applty
+ | C.Appl _ -> assert false
+ | C.Const (uri,exp_named_subst) ->
+ let exp_named_subst',subst',metasenv',ugraph1 =
+ check_exp_named_subst subst metasenv context
+ exp_named_subst ugraph in
+ let ty_uri,ugraph2 = type_of_constant uri ugraph1 in
+ let cty =
+ CicSubstitution.subst_vars exp_named_subst' ty_uri
+ in
+ C.Const (uri,exp_named_subst'),cty,subst',metasenv',ugraph2
+ | C.MutInd (uri,i,exp_named_subst) ->
+ let exp_named_subst',subst',metasenv',ugraph1 =
+ check_exp_named_subst subst metasenv context
+ exp_named_subst ugraph
+ in
+ let ty_uri,ugraph2 = type_of_mutual_inductive_defs uri i ugraph1 in
+ let cty =
+ CicSubstitution.subst_vars exp_named_subst' ty_uri in
+ C.MutInd (uri,i,exp_named_subst'),cty,subst',metasenv',ugraph2
+ | C.MutConstruct (uri,i,j,exp_named_subst) ->
+ let exp_named_subst',subst',metasenv',ugraph1 =
+ check_exp_named_subst subst metasenv context
+ exp_named_subst ugraph
+ in
+ let ty_uri,ugraph2 =
+ type_of_mutual_inductive_constr uri i j ugraph1
+ in
+ let cty =
+ CicSubstitution.subst_vars exp_named_subst' ty_uri
+ in
+ C.MutConstruct (uri,i,j,exp_named_subst'),cty,subst',
+ metasenv',ugraph2
+ | C.MutCase (uri, i, outtype, term, pl) ->
+ (* first, get the inductive type (and noparams)
+ * in the environment *)
+ let (_,b,arity,constructors), expl_params, no_left_params,ugraph =
+ let _ = CicTypeChecker.typecheck uri in
+ let obj,u = CicEnvironment.get_cooked_obj ugraph uri in
+ match obj with
+ C.InductiveDefinition (l,expl_params,parsno,_) ->
+ List.nth l i , expl_params, parsno, u
+ | _ ->
+ enrich localization_tbl t
+ (RefineFailure
+ (lazy ("Unkown mutual inductive definition " ^
+ U.string_of_uri uri)))
+ in
+ let rec count_prod t =
+ match CicReduction.whd ~subst context t with
+ C.Prod (_, _, t) -> 1 + (count_prod t)
+ | _ -> 0
+ in
+ let no_args = count_prod arity in
+ (* now, create a "generic" MutInd *)
+ let metasenv,left_args =
+ CicMkImplicit.n_fresh_metas metasenv subst context no_left_params
+ in
+ let metasenv,right_args =
+ let no_right_params = no_args - no_left_params in
+ if no_right_params < 0 then assert false
+ else CicMkImplicit.n_fresh_metas
+ metasenv subst context no_right_params
+ in
+ let metasenv,exp_named_subst =
+ CicMkImplicit.fresh_subst metasenv subst context expl_params in
+ let expected_type =
+ if no_args = 0 then
+ C.MutInd (uri,i,exp_named_subst)
+ else
+ C.Appl
+ (C.MutInd (uri,i,exp_named_subst)::(left_args @ right_args))
+ in
+ (* check consistency with the actual type of term *)
+ let term',actual_type,subst,metasenv,ugraph1 =
+ type_of_aux subst metasenv context term ugraph in
+ let expected_type',_, subst, metasenv,ugraph2 =
+ type_of_aux subst metasenv context expected_type ugraph1
+ in
+ let actual_type = CicReduction.whd ~subst context actual_type in
+ let subst,metasenv,ugraph3 =
+ try
+ fo_unif_subst subst context metasenv
+ expected_type' actual_type ugraph2
+ with
+ exn ->
+ enrich localization_tbl term' exn
+ ~f:(function _ ->
+ lazy ("The term " ^
+ CicMetaSubst.ppterm_in_context subst term'
+ context ^ " has type " ^
+ CicMetaSubst.ppterm_in_context subst actual_type
+ context ^ " but is here used with type " ^
+ CicMetaSubst.ppterm_in_context subst expected_type' context))
+ 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) =
+ List.fold_left
+ (fun (pl,j,outtypeinstances,subst,metasenv,ugraph) p ->
+ let constructor =
+ if left_args = [] then
+ (C.MutConstruct (uri,i,j,exp_named_subst))
+ else
+ (C.Appl
+ (C.MutConstruct (uri,i,j,exp_named_subst)::left_args))
+ in
+ let p',actual_type,subst,metasenv,ugraph1 =
+ type_of_aux subst metasenv context p ugraph
+ in
+ let constructor',expected_type, subst, metasenv,ugraph2 =
+ type_of_aux subst metasenv context constructor ugraph1
+ in
+ let outtypeinstance,subst,metasenv,ugraph3 =
+ check_branch 0 context metasenv subst no_left_params
+ actual_type constructor' expected_type ugraph2
+ in
+ (pl @ [p'],j+1,
+ outtypeinstance::outtypeinstances,subst,metasenv,ugraph3))
+ ([],1,[],subst,metasenv,ugraph3) pl
+ in
+
+ (* we are left to check that the outype matches his instances.
+ The easy case is when the outype is specified, that amount
+ to a trivial check. Otherwise, we should guess a type from
+ its instances
+ *)
+
+ let outtype,outtypety, subst, metasenv,ugraph4 =
+ type_of_aux subst metasenv context outtype ugraph4 in
+ (match outtype with
+ | C.Meta (n,l) ->
+ (let candidate,ugraph5,metasenv,subst =
+ let exp_name_subst, metasenv =
+ let o,_ =
+ CicEnvironment.get_cooked_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
+ | [] ->
+ 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',subst,metasenv =
+ CicMetaSubst.delift_rels subst metasenv
+ constructor_args_no instance
+ in
+ let candidate,ugraph,metasenv,subst =
+ List.fold_left (
+ fun (candidate_oty,ugraph,metasenv,subst)
+ (constructor_args_no,_,instance,_) ->
+ match candidate_oty with
+ | None -> None,ugraph,metasenv,subst
+ | Some ty ->
+ try
+ let instance',subst,metasenv =
+ CicMetaSubst.delift_rels subst metasenv
+ constructor_args_no instance
+ in
+ let subst,metasenv,ugraph =
+ fo_unif_subst subst context metasenv
+ instance' ty ugraph
+ in
+ 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 (lazy "can't solve an higher order unification problem"))
+ | Some candidate ->
+ let subst,metasenv,ugraph =
+ fo_unif_subst subst context metasenv
+ candidate outtype ugraph5
+ in
+ 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 tlbody_and_type,subst,metasenv,ugraph4 =
+ List.fold_right
+ (fun x (res,subst,metasenv,ugraph) ->
+ let x',ty,subst',metasenv',ugraph1 =
+ type_of_aux subst metasenv context x ugraph
+ in
+ (x', ty)::res,subst',metasenv',ugraph1
+ ) (right_args @ [term']) ([],subst,metasenv,ugraph4)