From: Enrico Tassi Date: Mon, 31 Jan 2005 17:11:14 +0000 (+0000) Subject: Added outtype inference to MutCase X-Git-Tag: V_0_1_0~87 X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=e98de6c5ff6d10baefd2d7492a8fdcd0a3fa1a6c;p=helm.git Added outtype inference to MutCase --- diff --git a/helm/ocaml/cic_unification/cicRefine.ml b/helm/ocaml/cic_unification/cicRefine.ml index d8b822d82..38e822c33 100644 --- a/helm/ocaml/cic_unification/cicRefine.ml +++ b/helm/ocaml/cic_unification/cicRefine.ml @@ -178,7 +178,9 @@ and check_branch n context metasenv subst left_args_no actualtype term expectedt | t -> C.Appl [t ; C.Rel 1]) in (* we should also check that the name variable is anonymous in the actual type de' ?? *) - check_branch (n+1) ((Some (name,(C.Decl so)))::context) metasenv subst left_args_no de' term' de ugraph1 + check_branch (n+1) + ((Some (name,(C.Decl so)))::context) + metasenv subst left_args_no de' term' de ugraph1 | _ -> raise (AssertFailure "Wrong number of arguments")) | _ -> raise (AssertFailure "Prod or MutInd expected") @@ -357,13 +359,6 @@ and type_of_aux' metasenv context t ugraph = (* first, get the inductive type (and noparams) * in the environment *) let (_,b,arity,constructors), expl_params, no_left_params,ugraph = - (* - let obj = - try - CicEnvironment.get_cooked_obj ~trust:true uri - with Not_found -> assert false - in - *) let obj,u = CicEnvironment.get_obj ugraph uri in match obj with C.InductiveDefinition (l,expl_params,parsno,_) -> @@ -373,115 +368,147 @@ and type_of_aux' metasenv context t ugraph = (RefineFailure ("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 = - fo_unif_subst subst context metasenv - expected_type' actual_type ugraph2 - 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 *) - - (* easy case *) - let _,_, subst, metasenv,ugraph5 = - type_of_aux subst metasenv context - (C.Appl ((outtype :: right_args) @ [term'])) ugraph4 - in - let (subst,metasenv,ugraph6) = - List.fold_left - (fun (subst,metasenv,ugraph) (constructor_args_no,context,instance,args) -> - let instance' = - let appl = - let outtype' = - CicSubstitution.lift constructor_args_no outtype + 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 = + fo_unif_subst subst context metasenv + expected_type' actual_type ugraph2 + 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 + *) + + (match outtype with + | C.Meta (n,l) -> + (let candidate,ugraph5 = + match outtypeinstances with + | [] -> raise (Uncertain "Inference of annotation for empty inductive types not implemented") + | (constructor_args_no,_,instance,_)::tl -> + try + let instance' = + CicSubstitution.delift constructor_args_no + (CicMetaSubst.apply_subst subst instance) in - C.Appl (outtype'::args) - in - (* - (* if appl is not well typed then the type_of below solves the - * problem *) - let (_, subst, metasenv,ugraph1) = - type_of_aux subst metasenv context appl ugraph - in - *) - (* DEBUG - let prova1 = CicMetaSubst.whd subst context appl in - let prova2 = CicReduction.whd ~subst context appl in - if not (prova1 = prova2) then - begin - prerr_endline ("prova1 =" ^ (CicPp.ppterm prova1)); - prerr_endline ("prova2 =" ^ (CicPp.ppterm prova2)); - end; - *) - (* CicMetaSubst.whd subst context appl *) - CicReduction.whd ~subst context appl - in - fo_unif_subst subst context metasenv - instance instance' ugraph) - (subst,metasenv,ugraph5) outtypeinstances - in - C.MutCase (uri, i, outtype, term', pl'), - CicReduction.whd ~subst context - (C.Appl(outtype::right_args@[term])), - subst,metasenv,ugraph6 + List.fold_left ( + fun (candidate_oty,ugraph) + (constructor_args_no,_,instance,_) -> + match candidate_oty with + | None -> None,ugraph + | Some ty -> + try + let instance' = + CicSubstitution.delift + constructor_args_no + (CicMetaSubst.apply_subst subst instance) + in + let b,ugraph1 = + CicReduction.are_convertible context + 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 + 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 = + fo_unif_subst subst context metasenv + candidate outtype ugraph5 + in + C.MutCase (uri, i, outtype, term', pl'),candidate,s,m,u) + | _ -> (* easy case *) + let _,_, subst, metasenv,ugraph5 = + type_of_aux subst metasenv context + (C.Appl ((outtype :: right_args) @ [term'])) ugraph4 + in + let (subst,metasenv,ugraph6) = + List.fold_left + (fun (subst,metasenv,ugraph) + (constructor_args_no,context,instance,args) -> + let instance' = + let appl = + let outtype' = + CicSubstitution.lift constructor_args_no outtype + in + C.Appl (outtype'::args) + in + CicReduction.whd ~subst context appl + in + fo_unif_subst subst context metasenv + instance instance' ugraph) + (subst,metasenv,ugraph5) outtypeinstances + in + C.MutCase (uri, i, outtype, term', pl'), + CicReduction.whd ~subst context + (C.Appl(outtype::right_args@[term])), + subst,metasenv,ugraph6) | C.Fix (i,fl) -> let fl_ty',subst,metasenv,types,ugraph1 = List.fold_left