(***********************************************************************) (* *) (* OCaml *) (* *) (* Jerome Vouillon, projet Cristal, INRIA Rocquencourt *) (* *) (* Copyright 1996 Institut National de Recherche en Informatique et *) (* en Automatique. All rights reserved. This file is distributed *) (* under the terms of the Q Public License version 1.0. *) (* *) (***********************************************************************) open Parsetree open Asttypes open Path open Types open Typecore open Typetexp open Format type error = Unconsistent_constraint of (type_expr * type_expr) list | Field_type_mismatch of string * string * (type_expr * type_expr) list | Structure_expected of class_type | Cannot_apply of class_type | Apply_wrong_label of label | Pattern_type_clash of type_expr | Repeated_parameter | Unbound_class_2 of Longident.t | Unbound_class_type_2 of Longident.t | Abbrev_type_clash of type_expr * type_expr * type_expr | Constructor_type_mismatch of string * (type_expr * type_expr) list | Virtual_class of bool * string list * string list | Parameter_arity_mismatch of Longident.t * int * int | Parameter_mismatch of (type_expr * type_expr) list | Bad_parameters of Ident.t * type_expr * type_expr | Class_match_failure of Ctype.class_match_failure list | Unbound_val of string | Unbound_type_var of (formatter -> unit) * Ctype.closed_class_failure | Make_nongen_seltype of type_expr | Non_generalizable_class of Ident.t * Types.class_declaration | Cannot_coerce_self of type_expr | Non_collapsable_conjunction of Ident.t * Types.class_declaration * (type_expr * type_expr) list | Final_self_clash of (type_expr * type_expr) list | Mutability_mismatch of string * mutable_flag | No_overriding of string * string exception Error of Location.t * Env.t * error open Typedtree let ctyp desc typ env loc = { ctyp_desc = desc; ctyp_type = typ; ctyp_loc = loc; ctyp_env = env } let cltyp desc typ env loc = { cltyp_desc = desc; cltyp_type = typ; cltyp_loc = loc; cltyp_env = env } let mkcf desc loc = { cf_desc = desc; cf_loc = loc } let mkctf desc loc = { ctf_desc = desc; ctf_loc = loc } (**********************) (* Useful constants *) (**********************) (* Self type have a dummy private method, thus preventing it to become closed. *) let dummy_method = Btype.dummy_method (* Path associated to the temporary class type of a class being typed (its constructor is not available). *) let unbound_class = Path.Pident (Ident.create "") (************************************) (* Some operations on class types *) (************************************) (* Fully expand the head of a class type *) let rec scrape_class_type = function Cty_constr (_, _, cty) -> scrape_class_type cty | cty -> cty (* Generalize a class type *) let rec generalize_class_type = function Cty_constr (_, params, cty) -> List.iter Ctype.generalize params; generalize_class_type cty | Cty_signature {cty_self = sty; cty_vars = vars; cty_inher = inher} -> Ctype.generalize sty; Vars.iter (fun _ (_, _, ty) -> Ctype.generalize ty) vars; List.iter (fun (_,tl) -> List.iter Ctype.generalize tl) inher | Cty_fun (_, ty, cty) -> Ctype.generalize ty; generalize_class_type cty (* Return the virtual methods of a class type *) let virtual_methods sign = let (fields, _) = Ctype.flatten_fields (Ctype.object_fields sign.cty_self) in List.fold_left (fun virt (lab, _, _) -> if lab = dummy_method then virt else if Concr.mem lab sign.cty_concr then virt else lab::virt) [] fields (* Return the constructor type associated to a class type *) let rec constructor_type constr cty = match cty with Cty_constr (_, _, cty) -> constructor_type constr cty | Cty_signature sign -> constr | Cty_fun (l, ty, cty) -> Ctype.newty (Tarrow (l, ty, constructor_type constr cty, Cok)) let rec class_body cty = match cty with Cty_constr (_, _, cty') -> cty (* Only class bodies can be abbreviated *) | Cty_signature sign -> cty | Cty_fun (_, ty, cty) -> class_body cty let extract_constraints cty = let sign = Ctype.signature_of_class_type cty in (Vars.fold (fun lab _ vars -> lab :: vars) sign.cty_vars [], begin let (fields, _) = Ctype.flatten_fields (Ctype.object_fields sign.cty_self) in List.fold_left (fun meths (lab, _, _) -> if lab = dummy_method then meths else lab::meths) [] fields end, sign.cty_concr) let rec abbreviate_class_type path params cty = match cty with Cty_constr (_, _, _) | Cty_signature _ -> Cty_constr (path, params, cty) | Cty_fun (l, ty, cty) -> Cty_fun (l, ty, abbreviate_class_type path params cty) let rec closed_class_type = function Cty_constr (_, params, _) -> List.for_all Ctype.closed_schema params | Cty_signature sign -> Ctype.closed_schema sign.cty_self && Vars.fold (fun _ (_, _, ty) cc -> Ctype.closed_schema ty && cc) sign.cty_vars true | Cty_fun (_, ty, cty) -> Ctype.closed_schema ty && closed_class_type cty let closed_class cty = List.for_all Ctype.closed_schema cty.cty_params && closed_class_type cty.cty_type let rec limited_generalize rv = function Cty_constr (path, params, cty) -> List.iter (Ctype.limited_generalize rv) params; limited_generalize rv cty | Cty_signature sign -> Ctype.limited_generalize rv sign.cty_self; Vars.iter (fun _ (_, _, ty) -> Ctype.limited_generalize rv ty) sign.cty_vars; List.iter (fun (_, tl) -> List.iter (Ctype.limited_generalize rv) tl) sign.cty_inher | Cty_fun (_, ty, cty) -> Ctype.limited_generalize rv ty; limited_generalize rv cty (* Record a class type *) let rc node = Cmt_format.add_saved_type (Cmt_format.Partial_class_expr node); Stypes.record (Stypes.Ti_class node); (* moved to genannot *) node (***********************************) (* Primitives for typing classes *) (***********************************) (* Enter a value in the method environment only *) let enter_met_env ?check loc lab kind ty val_env met_env par_env = let (id, val_env) = Env.enter_value lab {val_type = ty; val_kind = Val_unbound; Types.val_loc = loc} val_env in (id, val_env, Env.add_value ?check id {val_type = ty; val_kind = kind; Types.val_loc = loc} met_env, Env.add_value id {val_type = ty; val_kind = Val_unbound; Types.val_loc = loc} par_env) (* Enter an instance variable in the environment *) let enter_val cl_num vars inh lab mut virt ty val_env met_env par_env loc = let instance = Ctype.instance val_env in let (id, virt) = try let (id, mut', virt', ty') = Vars.find lab !vars in if mut' <> mut then raise (Error(loc, val_env, Mutability_mismatch(lab, mut))); Ctype.unify val_env (instance ty) (instance ty'); (if not inh then Some id else None), (if virt' = Concrete then virt' else virt) with Ctype.Unify tr -> raise (Error(loc, val_env, Field_type_mismatch("instance variable", lab, tr))) | Not_found -> None, virt in let (id, _, _, _) as result = match id with Some id -> (id, val_env, met_env, par_env) | None -> enter_met_env Location.none lab (Val_ivar (mut, cl_num)) ty val_env met_env par_env in vars := Vars.add lab (id, mut, virt, ty) !vars; result let concr_vals vars = Vars.fold (fun id (_, vf, _) s -> if vf = Virtual then s else Concr.add id s) vars Concr.empty let inheritance self_type env ovf concr_meths warn_vals loc parent = match scrape_class_type parent with Cty_signature cl_sig -> (* Methods *) begin try Ctype.unify env self_type cl_sig.cty_self with Ctype.Unify trace -> match trace with _::_::_::({desc = Tfield(n, _, _, _)}, _)::rem -> raise(Error(loc, env, Field_type_mismatch ("method", n, rem))) | _ -> assert false end; (* Overriding *) let over_meths = Concr.inter cl_sig.cty_concr concr_meths in let concr_vals = concr_vals cl_sig.cty_vars in let over_vals = Concr.inter concr_vals warn_vals in begin match ovf with Some Fresh -> let cname = match parent with Cty_constr (p, _, _) -> Path.name p | _ -> "inherited" in if not (Concr.is_empty over_meths) then Location.prerr_warning loc (Warnings.Method_override (cname :: Concr.elements over_meths)); if not (Concr.is_empty over_vals) then Location.prerr_warning loc (Warnings.Instance_variable_override (cname :: Concr.elements over_vals)); | Some Override when Concr.is_empty over_meths && Concr.is_empty over_vals -> raise (Error(loc, env, No_overriding ("",""))) | _ -> () end; let concr_meths = Concr.union cl_sig.cty_concr concr_meths and warn_vals = Concr.union concr_vals warn_vals in (cl_sig, concr_meths, warn_vals) | _ -> raise(Error(loc, env, Structure_expected parent)) let virtual_method val_env meths self_type lab priv sty loc = let (_, ty') = Ctype.filter_self_method val_env lab priv meths self_type in let cty = transl_simple_type val_env false sty in let ty = cty.ctyp_type in begin try Ctype.unify val_env ty ty' with Ctype.Unify trace -> raise(Error(loc, val_env, Field_type_mismatch ("method", lab, trace))); end; cty let delayed_meth_specs = ref [] let declare_method val_env meths self_type lab priv sty loc = let (_, ty') = Ctype.filter_self_method val_env lab priv meths self_type in let unif ty = try Ctype.unify val_env ty ty' with Ctype.Unify trace -> raise(Error(loc, val_env, Field_type_mismatch ("method", lab, trace))) in match sty.ptyp_desc, priv with Ptyp_poly ([],sty'), Public -> (* TODO: we moved the [transl_simple_type_univars] outside of the lazy, so that we can get an immediate value. Is that correct ? Ask Jacques. *) let returned_cty = ctyp Ttyp_any (Ctype.newty Tnil) val_env loc in delayed_meth_specs := lazy ( let cty = transl_simple_type_univars val_env sty' in let ty = cty.ctyp_type in unif ty; returned_cty.ctyp_desc <- Ttyp_poly ([], cty); returned_cty.ctyp_type <- ty; ) :: !delayed_meth_specs; returned_cty | _ -> let cty = transl_simple_type val_env false sty in let ty = cty.ctyp_type in unif ty; cty let type_constraint val_env sty sty' loc = let cty = transl_simple_type val_env false sty in let ty = cty.ctyp_type in let cty' = transl_simple_type val_env false sty' in let ty' = cty'.ctyp_type in begin try Ctype.unify val_env ty ty' with Ctype.Unify trace -> raise(Error(loc, val_env, Unconsistent_constraint trace)); end; (cty, cty') let make_method self_loc cl_num expr = let mkpat d = { ppat_desc = d; ppat_loc = self_loc } in let mkid s = mkloc s self_loc in { pexp_desc = Pexp_function ("", None, [mkpat (Ppat_alias (mkpat (Ppat_var (mkid "self-*")), mkid ("self-" ^ cl_num))), expr]); pexp_loc = expr.pexp_loc } (*******************************) let add_val env loc lab (mut, virt, ty) val_sig = let virt = try let (mut', virt', ty') = Vars.find lab val_sig in if virt' = Concrete then virt' else virt with Not_found -> virt in Vars.add lab (mut, virt, ty) val_sig let rec class_type_field env self_type meths (fields, val_sig, concr_meths, inher) ctf = let loc = ctf.pctf_loc in match ctf.pctf_desc with Pctf_inher sparent -> let parent = class_type env sparent in let inher = match parent.cltyp_type with Cty_constr (p, tl, _) -> (p, tl) :: inher | _ -> inher in let (cl_sig, concr_meths, _) = inheritance self_type env None concr_meths Concr.empty sparent.pcty_loc parent.cltyp_type in let val_sig = Vars.fold (add_val env sparent.pcty_loc) cl_sig.cty_vars val_sig in (mkctf (Tctf_inher parent) loc :: fields, val_sig, concr_meths, inher) | Pctf_val (lab, mut, virt, sty) -> let cty = transl_simple_type env false sty in let ty = cty.ctyp_type in (mkctf (Tctf_val (lab, mut, virt, cty)) loc :: fields, add_val env ctf.pctf_loc lab (mut, virt, ty) val_sig, concr_meths, inher) | Pctf_virt (lab, priv, sty) -> let cty = declare_method env meths self_type lab priv sty ctf.pctf_loc in (mkctf (Tctf_virt (lab, priv, cty)) loc :: fields, val_sig, concr_meths, inher) | Pctf_meth (lab, priv, sty) -> let cty = declare_method env meths self_type lab priv sty ctf.pctf_loc in (mkctf (Tctf_meth (lab, priv, cty)) loc :: fields, val_sig, Concr.add lab concr_meths, inher) | Pctf_cstr (sty, sty') -> let (cty, cty') = type_constraint env sty sty' ctf.pctf_loc in (mkctf (Tctf_cstr (cty, cty')) loc :: fields, val_sig, concr_meths, inher) and class_signature env sty sign loc = let meths = ref Meths.empty in let self_cty = transl_simple_type env false sty in let self_cty = { self_cty with ctyp_type = Ctype.expand_head env self_cty.ctyp_type } in let self_type = self_cty.ctyp_type in (* Check that the binder is a correct type, and introduce a dummy method preventing self type from being closed. *) let dummy_obj = Ctype.newvar () in Ctype.unify env (Ctype.filter_method env dummy_method Private dummy_obj) (Ctype.newty (Ttuple [])); begin try Ctype.unify env self_type dummy_obj with Ctype.Unify _ -> raise(Error(sty.ptyp_loc, env, Pattern_type_clash self_type)) end; (* Class type fields *) let (fields, val_sig, concr_meths, inher) = List.fold_left (class_type_field env self_type meths) ([], Vars.empty, Concr.empty, []) sign in let cty = {cty_self = self_type; cty_vars = val_sig; cty_concr = concr_meths; cty_inher = inher} in { csig_self = self_cty; csig_fields = fields; csig_type = cty; csig_loc = loc; } and class_type env scty = let loc = scty.pcty_loc in match scty.pcty_desc with Pcty_constr (lid, styl) -> let (path, decl) = Typetexp.find_class_type env scty.pcty_loc lid.txt in if Path.same decl.clty_path unbound_class then raise(Error(scty.pcty_loc, env, Unbound_class_type_2 lid.txt)); let (params, clty) = Ctype.instance_class decl.clty_params decl.clty_type in if List.length params <> List.length styl then raise(Error(scty.pcty_loc, env, Parameter_arity_mismatch (lid.txt, List.length params, List.length styl))); let ctys = List.map2 (fun sty ty -> let cty' = transl_simple_type env false sty in let ty' = cty'.ctyp_type in begin try Ctype.unify env ty' ty with Ctype.Unify trace -> raise(Error(sty.ptyp_loc, env, Parameter_mismatch trace)) end; cty' ) styl params in let typ = Cty_constr (path, params, clty) in cltyp (Tcty_constr ( path, lid , ctys)) typ env loc | Pcty_signature pcsig -> let clsig = class_signature env pcsig.pcsig_self pcsig.pcsig_fields pcsig.pcsig_loc in let typ = Cty_signature clsig.csig_type in cltyp (Tcty_signature clsig) typ env loc | Pcty_fun (l, sty, scty) -> let cty = transl_simple_type env false sty in let ty = cty.ctyp_type in let clty = class_type env scty in let typ = Cty_fun (l, ty, clty.cltyp_type) in cltyp (Tcty_fun (l, cty, clty)) typ env loc let class_type env scty = delayed_meth_specs := []; let cty = class_type env scty in List.iter Lazy.force (List.rev !delayed_meth_specs); delayed_meth_specs := []; cty (*******************************) let rec class_field self_loc cl_num self_type meths vars (val_env, met_env, par_env, fields, concr_meths, warn_vals, inher) cf = let loc = cf.pcf_loc in match cf.pcf_desc with Pcf_inher (ovf, sparent, super) -> let parent = class_expr cl_num val_env par_env sparent in let inher = match parent.cl_type with Cty_constr (p, tl, _) -> (p, tl) :: inher | _ -> inher in let (cl_sig, concr_meths, warn_vals) = inheritance self_type val_env (Some ovf) concr_meths warn_vals sparent.pcl_loc parent.cl_type in (* Variables *) let (val_env, met_env, par_env, inh_vars) = Vars.fold (fun lab info (val_env, met_env, par_env, inh_vars) -> let mut, vr, ty = info in let (id, val_env, met_env, par_env) = enter_val cl_num vars true lab mut vr ty val_env met_env par_env sparent.pcl_loc in (val_env, met_env, par_env, (lab, id) :: inh_vars)) cl_sig.cty_vars (val_env, met_env, par_env, []) in (* Inherited concrete methods *) let inh_meths = Concr.fold (fun lab rem -> (lab, Ident.create lab)::rem) cl_sig.cty_concr [] in (* Super *) let (val_env, met_env, par_env) = match super with None -> (val_env, met_env, par_env) | Some name -> let (id, val_env, met_env, par_env) = enter_met_env ~check:(fun s -> Warnings.Unused_ancestor s) sparent.pcl_loc name (Val_anc (inh_meths, cl_num)) self_type val_env met_env par_env in (val_env, met_env, par_env) in (val_env, met_env, par_env, lazy (mkcf (Tcf_inher (ovf, parent, super, inh_vars, inh_meths)) loc) :: fields, concr_meths, warn_vals, inher) | Pcf_valvirt (lab, mut, styp) -> if !Clflags.principal then Ctype.begin_def (); let cty = Typetexp.transl_simple_type val_env false styp in let ty = cty.ctyp_type in if !Clflags.principal then begin Ctype.end_def (); Ctype.generalize_structure ty end; let (id, val_env, met_env', par_env) = enter_val cl_num vars false lab.txt mut Virtual ty val_env met_env par_env loc in (val_env, met_env', par_env, lazy (mkcf (Tcf_val (lab.txt, lab, mut, id, Tcfk_virtual cty, met_env' == met_env)) loc) :: fields, concr_meths, warn_vals, inher) | Pcf_val (lab, mut, ovf, sexp) -> if Concr.mem lab.txt warn_vals then begin if ovf = Fresh then Location.prerr_warning lab.loc (Warnings.Instance_variable_override[lab.txt]) end else begin if ovf = Override then raise(Error(loc, val_env, No_overriding ("instance variable", lab.txt))) end; if !Clflags.principal then Ctype.begin_def (); let exp = try type_exp val_env sexp with Ctype.Unify [(ty, _)] -> raise(Error(loc, val_env, Make_nongen_seltype ty)) in if !Clflags.principal then begin Ctype.end_def (); Ctype.generalize_structure exp.exp_type end; let (id, val_env, met_env', par_env) = enter_val cl_num vars false lab.txt mut Concrete exp.exp_type val_env met_env par_env loc in (val_env, met_env', par_env, lazy (mkcf (Tcf_val (lab.txt, lab, mut, id, Tcfk_concrete exp, met_env' == met_env)) loc) :: fields, concr_meths, Concr.add lab.txt warn_vals, inher) | Pcf_virt (lab, priv, sty) -> let cty = virtual_method val_env meths self_type lab.txt priv sty loc in (val_env, met_env, par_env, lazy (mkcf(Tcf_meth (lab.txt, lab, priv, Tcfk_virtual cty, true)) loc) ::fields, concr_meths, warn_vals, inher) | Pcf_meth (lab, priv, ovf, expr) -> if Concr.mem lab.txt concr_meths then begin if ovf = Fresh then Location.prerr_warning loc (Warnings.Method_override [lab.txt]) end else begin if ovf = Override then raise(Error(loc, val_env, No_overriding("method", lab.txt))) end; let (_, ty) = Ctype.filter_self_method val_env lab.txt priv meths self_type in begin try match expr.pexp_desc with Pexp_poly (sbody, sty) -> begin match sty with None -> () | Some sty -> let cty' = Typetexp.transl_simple_type val_env false sty in let ty' = cty'.ctyp_type in Ctype.unify val_env ty' ty end; begin match (Ctype.repr ty).desc with Tvar _ -> let ty' = Ctype.newvar () in Ctype.unify val_env (Ctype.newty (Tpoly (ty', []))) ty; Ctype.unify val_env (type_approx val_env sbody) ty' | Tpoly (ty1, tl) -> let _, ty1' = Ctype.instance_poly false tl ty1 in let ty2 = type_approx val_env sbody in Ctype.unify val_env ty2 ty1' | _ -> assert false end | _ -> assert false with Ctype.Unify trace -> raise(Error(loc, val_env, Field_type_mismatch ("method", lab.txt, trace))) end; let meth_expr = make_method self_loc cl_num expr in (* backup variables for Pexp_override *) let vars_local = !vars in let field = lazy begin let meth_type = Btype.newgenty (Tarrow("", self_type, ty, Cok)) in Ctype.raise_nongen_level (); vars := vars_local; let texp = type_expect met_env meth_expr meth_type in Ctype.end_def (); mkcf (Tcf_meth (lab.txt, lab, priv, Tcfk_concrete texp, match ovf with Override -> true | Fresh -> false)) loc end in (val_env, met_env, par_env, field::fields, Concr.add lab.txt concr_meths, warn_vals, inher) | Pcf_constr (sty, sty') -> let (cty, cty') = type_constraint val_env sty sty' loc in (val_env, met_env, par_env, lazy (mkcf (Tcf_constr (cty, cty')) loc) :: fields, concr_meths, warn_vals, inher) | Pcf_init expr -> let expr = make_method self_loc cl_num expr in let vars_local = !vars in let field = lazy begin Ctype.raise_nongen_level (); let meth_type = Ctype.newty (Tarrow ("", self_type, Ctype.instance_def Predef.type_unit, Cok)) in vars := vars_local; let texp = type_expect met_env expr meth_type in Ctype.end_def (); mkcf (Tcf_init texp) loc end in (val_env, met_env, par_env, field::fields, concr_meths, warn_vals, inher) and class_structure cl_num final val_env met_env loc { pcstr_pat = spat; pcstr_fields = str } = (* Environment for substructures *) let par_env = met_env in (* Location of self. Used for locations of self arguments *) let self_loc = {spat.ppat_loc with Location.loc_ghost = true} in (* Self type, with a dummy method preventing it from being closed/escaped. *) let self_type = Ctype.newvar () in Ctype.unify val_env (Ctype.filter_method val_env dummy_method Private self_type) (Ctype.newty (Ttuple [])); (* Private self is used for private method calls *) let private_self = if final then Ctype.newvar () else self_type in (* Self binder *) let (pat, meths, vars, val_env, meth_env, par_env) = type_self_pattern cl_num private_self val_env met_env par_env spat in let public_self = pat.pat_type in (* Check that the binder has a correct type *) let ty = if final then Ctype.newty (Tobject (Ctype.newvar(), ref None)) else self_type in begin try Ctype.unify val_env public_self ty with Ctype.Unify _ -> raise(Error(spat.ppat_loc, val_env, Pattern_type_clash public_self)) end; let get_methods ty = (fst (Ctype.flatten_fields (Ctype.object_fields (Ctype.expand_head val_env ty)))) in if final then begin (* Copy known information to still empty self_type *) List.iter (fun (lab,kind,ty) -> let k = if Btype.field_kind_repr kind = Fpresent then Public else Private in try Ctype.unify val_env ty (Ctype.filter_method val_env lab k self_type) with _ -> assert false) (get_methods public_self) end; (* Typing of class fields *) let (_, _, _, fields, concr_meths, _, inher) = List.fold_left (class_field self_loc cl_num self_type meths vars) (val_env, meth_env, par_env, [], Concr.empty, Concr.empty, []) str in Ctype.unify val_env self_type (Ctype.newvar ()); let sign = {cty_self = public_self; cty_vars = Vars.map (fun (id, mut, vr, ty) -> (mut, vr, ty)) !vars; cty_concr = concr_meths; cty_inher = inher} in let methods = get_methods self_type in let priv_meths = List.filter (fun (_,kind,_) -> Btype.field_kind_repr kind <> Fpresent) methods in if final then begin (* Unify private_self and a copy of self_type. self_type will not be modified after this point *) Ctype.close_object self_type; let mets = virtual_methods {sign with cty_self = self_type} in let vals = Vars.fold (fun name (mut, vr, ty) l -> if vr = Virtual then name :: l else l) sign.cty_vars [] in if mets <> [] || vals <> [] then raise(Error(loc, val_env, Virtual_class(true, mets, vals))); let self_methods = List.fold_right (fun (lab,kind,ty) rem -> if lab = dummy_method then (* allow public self and private self to be unified *) match Btype.field_kind_repr kind with Fvar r -> Btype.set_kind r Fabsent; rem | _ -> rem else Ctype.newty(Tfield(lab, Btype.copy_kind kind, ty, rem))) methods (Ctype.newty Tnil) in begin try Ctype.unify val_env private_self (Ctype.newty (Tobject(self_methods, ref None))); Ctype.unify val_env public_self self_type with Ctype.Unify trace -> raise(Error(loc, val_env, Final_self_clash trace)) end; end; (* Typing of method bodies *) if !Clflags.principal then List.iter (fun (_,_,ty) -> Ctype.generalize_spine ty) methods; let fields = List.map Lazy.force (List.rev fields) in if !Clflags.principal then List.iter (fun (_,_,ty) -> Ctype.unify val_env ty (Ctype.newvar ())) methods; let meths = Meths.map (function (id, ty) -> id) !meths in (* Check for private methods made public *) let pub_meths' = List.filter (fun (_,kind,_) -> Btype.field_kind_repr kind = Fpresent) (get_methods public_self) in let names = List.map (fun (x,_,_) -> x) in let l1 = names priv_meths and l2 = names pub_meths' in let added = List.filter (fun x -> List.mem x l1) l2 in if added <> [] then Location.prerr_warning loc (Warnings.Implicit_public_methods added); let sign = if final then sign else {sign with cty_self = Ctype.expand_head val_env public_self} in { cstr_pat = pat; cstr_fields = fields; cstr_type = sign; cstr_meths = meths}, sign (* redondant, since already in cstr_type *) and class_expr cl_num val_env met_env scl = match scl.pcl_desc with Pcl_constr (lid, styl) -> let (path, decl) = Typetexp.find_class val_env scl.pcl_loc lid.txt in if Path.same decl.cty_path unbound_class then raise(Error(scl.pcl_loc, val_env, Unbound_class_2 lid.txt)); let tyl = List.map (fun sty -> transl_simple_type val_env false sty) styl in let (params, clty) = Ctype.instance_class decl.cty_params decl.cty_type in let clty' = abbreviate_class_type path params clty in if List.length params <> List.length tyl then raise(Error(scl.pcl_loc, val_env, Parameter_arity_mismatch (lid.txt, List.length params, List.length tyl))); List.iter2 (fun cty' ty -> let ty' = cty'.ctyp_type in try Ctype.unify val_env ty' ty with Ctype.Unify trace -> raise(Error(cty'.ctyp_loc, val_env, Parameter_mismatch trace))) tyl params; let cl = rc {cl_desc = Tcl_ident (path, lid, tyl); cl_loc = scl.pcl_loc; cl_type = clty'; cl_env = val_env} in let (vals, meths, concrs) = extract_constraints clty in rc {cl_desc = Tcl_constraint (cl, None, vals, meths, concrs); cl_loc = scl.pcl_loc; cl_type = clty'; cl_env = val_env} | Pcl_structure cl_str -> let (desc, ty) = class_structure cl_num false val_env met_env scl.pcl_loc cl_str in rc {cl_desc = Tcl_structure desc; cl_loc = scl.pcl_loc; cl_type = Cty_signature ty; cl_env = val_env} | Pcl_fun (l, Some default, spat, sbody) -> let loc = default.pexp_loc in let scases = [{ppat_loc = loc; ppat_desc = Ppat_construct ( mknoloc (Longident.(Ldot (Lident"*predef*", "Some"))), Some{ppat_loc = loc; ppat_desc = Ppat_var (mknoloc "*sth*")}, false)}, {pexp_loc = loc; pexp_desc = Pexp_ident(mknoloc (Longident.Lident"*sth*"))}; {ppat_loc = loc; ppat_desc = Ppat_construct(mknoloc (Longident.(Ldot (Lident"*predef*", "None"))), None, false)}, default] in let smatch = {pexp_loc = loc; pexp_desc = Pexp_match({pexp_loc = loc; pexp_desc = Pexp_ident(mknoloc (Longident.Lident"*opt*"))}, scases)} in let sfun = {pcl_loc = scl.pcl_loc; pcl_desc = Pcl_fun(l, None, {ppat_loc = loc; ppat_desc = Ppat_var (mknoloc "*opt*")}, {pcl_loc = scl.pcl_loc; pcl_desc = Pcl_let(Default, [spat, smatch], sbody)})} in class_expr cl_num val_env met_env sfun | Pcl_fun (l, None, spat, scl') -> if !Clflags.principal then Ctype.begin_def (); let (pat, pv, val_env', met_env) = Typecore.type_class_arg_pattern cl_num val_env met_env l spat in if !Clflags.principal then begin Ctype.end_def (); iter_pattern (fun {pat_type=ty} -> Ctype.generalize_structure ty) pat end; let pv = List.map begin fun (id, id_loc, id', ty) -> let path = Pident id' in (* do not mark the value as being used *) let vd = Env.find_value path val_env' in (id, id_loc, {exp_desc = Texp_ident(path, mknoloc (Longident.Lident (Ident.name id)), vd); exp_loc = Location.none; exp_extra = []; exp_type = Ctype.instance val_env' vd.val_type; exp_env = val_env'}) end pv in let not_function = function Cty_fun _ -> false | _ -> true in let partial = Parmatch.check_partial pat.pat_loc [pat, (* Dummy expression *) {exp_desc = Texp_constant (Asttypes.Const_int 1); exp_loc = Location.none; exp_extra = []; exp_type = Ctype.none; exp_env = Env.empty }] in Ctype.raise_nongen_level (); let cl = class_expr cl_num val_env' met_env scl' in Ctype.end_def (); if Btype.is_optional l && not_function cl.cl_type then Location.prerr_warning pat.pat_loc Warnings.Unerasable_optional_argument; rc {cl_desc = Tcl_fun (l, pat, pv, cl, partial); cl_loc = scl.pcl_loc; cl_type = Cty_fun (l, Ctype.instance_def pat.pat_type, cl.cl_type); cl_env = val_env} | Pcl_apply (scl', sargs) -> let cl = class_expr cl_num val_env met_env scl' in let rec nonopt_labels ls ty_fun = match ty_fun with | Cty_fun (l, _, ty_res) -> if Btype.is_optional l then nonopt_labels ls ty_res else nonopt_labels (l::ls) ty_res | _ -> ls in let ignore_labels = !Clflags.classic || let labels = nonopt_labels [] cl.cl_type in List.length labels = List.length sargs && List.for_all (fun (l,_) -> l = "") sargs && List.exists (fun l -> l <> "") labels && begin Location.prerr_warning cl.cl_loc Warnings.Labels_omitted; true end in let rec type_args args omitted ty_fun sargs more_sargs = match ty_fun with | Cty_fun (l, ty, ty_fun) when sargs <> [] || more_sargs <> [] -> let name = Btype.label_name l and optional = if Btype.is_optional l then Optional else Required in let sargs, more_sargs, arg = if ignore_labels && not (Btype.is_optional l) then begin match sargs, more_sargs with (l', sarg0)::_, _ -> raise(Error(sarg0.pexp_loc, val_env, Apply_wrong_label l')) | _, (l', sarg0)::more_sargs -> if l <> l' && l' <> "" then raise(Error(sarg0.pexp_loc, val_env, Apply_wrong_label l')) else ([], more_sargs, Some (type_argument val_env sarg0 ty ty)) | _ -> assert false end else try let (l', sarg0, sargs, more_sargs) = try let (l', sarg0, sargs1, sargs2) = Btype.extract_label name sargs in (l', sarg0, sargs1 @ sargs2, more_sargs) with Not_found -> let (l', sarg0, sargs1, sargs2) = Btype.extract_label name more_sargs in (l', sarg0, sargs @ sargs1, sargs2) in if optional = Required && Btype.is_optional l' then Location.prerr_warning sarg0.pexp_loc (Warnings.Nonoptional_label l); sargs, more_sargs, if optional = Required || Btype.is_optional l' then Some (type_argument val_env sarg0 ty ty) else let ty0 = extract_option_type val_env ty in let arg = type_argument val_env sarg0 ty0 ty0 in Some (option_some arg) with Not_found -> sargs, more_sargs, if Btype.is_optional l && (List.mem_assoc "" sargs || List.mem_assoc "" more_sargs) then Some (option_none ty Location.none) else None in let omitted = if arg = None then (l,ty) :: omitted else omitted in type_args ((l,arg,optional)::args) omitted ty_fun sargs more_sargs | _ -> match sargs @ more_sargs with (l, sarg0)::_ -> if omitted <> [] then raise(Error(sarg0.pexp_loc, val_env, Apply_wrong_label l)) else raise(Error(cl.cl_loc, val_env, Cannot_apply cl.cl_type)) | [] -> (List.rev args, List.fold_left (fun ty_fun (l,ty) -> Cty_fun(l,ty,ty_fun)) ty_fun omitted) in let (args, cty) = if ignore_labels then type_args [] [] cl.cl_type [] sargs else type_args [] [] cl.cl_type sargs [] in rc {cl_desc = Tcl_apply (cl, args); cl_loc = scl.pcl_loc; cl_type = cty; cl_env = val_env} | Pcl_let (rec_flag, sdefs, scl') -> let (defs, val_env) = try Typecore.type_let val_env rec_flag sdefs None with Ctype.Unify [(ty, _)] -> raise(Error(scl.pcl_loc, val_env, Make_nongen_seltype ty)) in let (vals, met_env) = List.fold_right (fun (id, id_loc) (vals, met_env) -> let path = Pident id in (* do not mark the value as used *) let vd = Env.find_value path val_env in Ctype.begin_def (); let expr = {exp_desc = Texp_ident(path, mknoloc(Longident.Lident (Ident.name id)),vd); exp_loc = Location.none; exp_extra = []; exp_type = Ctype.instance val_env vd.val_type; exp_env = val_env; } in Ctype.end_def (); Ctype.generalize expr.exp_type; let desc = {val_type = expr.exp_type; val_kind = Val_ivar (Immutable, cl_num); Types.val_loc = vd.Types.val_loc; } in let id' = Ident.create (Ident.name id) in ((id', id_loc, expr) :: vals, Env.add_value id' desc met_env)) (let_bound_idents_with_loc defs) ([], met_env) in let cl = class_expr cl_num val_env met_env scl' in rc {cl_desc = Tcl_let (rec_flag, defs, vals, cl); cl_loc = scl.pcl_loc; cl_type = cl.cl_type; cl_env = val_env} | Pcl_constraint (scl', scty) -> Ctype.begin_class_def (); let context = Typetexp.narrow () in let cl = class_expr cl_num val_env met_env scl' in Typetexp.widen context; let context = Typetexp.narrow () in let clty = class_type val_env scty in Typetexp.widen context; Ctype.end_def (); limited_generalize (Ctype.row_variable (Ctype.self_type cl.cl_type)) cl.cl_type; limited_generalize (Ctype.row_variable (Ctype.self_type clty.cltyp_type)) clty.cltyp_type; begin match Includeclass.class_types val_env cl.cl_type clty.cltyp_type with [] -> () | error -> raise(Error(cl.cl_loc, val_env, Class_match_failure error)) end; let (vals, meths, concrs) = extract_constraints clty.cltyp_type in rc {cl_desc = Tcl_constraint (cl, Some clty, vals, meths, concrs); cl_loc = scl.pcl_loc; cl_type = snd (Ctype.instance_class [] clty.cltyp_type); cl_env = val_env} (*******************************) (* Approximate the type of the constructor to allow recursive use *) (* of optional parameters *) let var_option = Predef.type_option (Btype.newgenvar ()) let rec approx_declaration cl = match cl.pcl_desc with Pcl_fun (l, _, _, cl) -> let arg = if Btype.is_optional l then Ctype.instance_def var_option else Ctype.newvar () in Ctype.newty (Tarrow (l, arg, approx_declaration cl, Cok)) | Pcl_let (_, _, cl) -> approx_declaration cl | Pcl_constraint (cl, _) -> approx_declaration cl | _ -> Ctype.newvar () let rec approx_description ct = match ct.pcty_desc with Pcty_fun (l, _, ct) -> let arg = if Btype.is_optional l then Ctype.instance_def var_option else Ctype.newvar () in Ctype.newty (Tarrow (l, arg, approx_description ct, Cok)) | _ -> Ctype.newvar () (*******************************) let temp_abbrev loc env id arity = let params = ref [] in for _i = 1 to arity do params := Ctype.newvar () :: !params done; let ty = Ctype.newobj (Ctype.newvar ()) in let env = Env.add_type id {type_params = !params; type_arity = arity; type_kind = Type_abstract; type_private = Public; type_manifest = Some ty; type_variance = List.map (fun _ -> true, true, true) !params; type_newtype_level = None; type_loc = loc; } env in (!params, ty, env) let initial_env define_class approx (res, env) (cl, id, ty_id, obj_id, cl_id) = (* Temporary abbreviations *) let arity = List.length (fst cl.pci_params) in let (obj_params, obj_ty, env) = temp_abbrev cl.pci_loc env obj_id arity in let (cl_params, cl_ty, env) = temp_abbrev cl.pci_loc env cl_id arity in (* Temporary type for the class constructor *) let constr_type = approx cl.pci_expr in if !Clflags.principal then Ctype.generalize_spine constr_type; let dummy_cty = Cty_signature { cty_self = Ctype.newvar (); cty_vars = Vars.empty; cty_concr = Concr.empty; cty_inher = [] } in let dummy_class = {cty_params = []; (* Dummy value *) cty_variance = []; cty_type = dummy_cty; (* Dummy value *) cty_path = unbound_class; cty_new = match cl.pci_virt with Virtual -> None | Concrete -> Some constr_type} in let env = Env.add_cltype ty_id {clty_params = []; (* Dummy value *) clty_variance = []; clty_type = dummy_cty; (* Dummy value *) clty_path = unbound_class} ( if define_class then Env.add_class id dummy_class env else env) in ((cl, id, ty_id, obj_id, obj_params, obj_ty, cl_id, cl_params, cl_ty, constr_type, dummy_class)::res, env) let class_infos define_class kind (cl, id, ty_id, obj_id, obj_params, obj_ty, cl_id, cl_params, cl_ty, constr_type, dummy_class) (res, env) = reset_type_variables (); Ctype.begin_class_def (); (* Introduce class parameters *) let params = try let params, loc = cl.pci_params in List.map (fun x -> enter_type_variable true loc x.txt) params with Already_bound -> raise(Error(snd cl.pci_params, env, Repeated_parameter)) in (* Allow self coercions (only for class declarations) *) let coercion_locs = ref [] in (* Type the class expression *) let (expr, typ) = try Typecore.self_coercion := (Path.Pident obj_id, coercion_locs) :: !Typecore.self_coercion; let res = kind env cl.pci_expr in Typecore.self_coercion := List.tl !Typecore.self_coercion; res with exn -> Typecore.self_coercion := []; raise exn in Ctype.end_def (); let sty = Ctype.self_type typ in ignore (Ctype.object_fields sty); (* Generalize the row variable *) let rv = Ctype.row_variable sty in List.iter (Ctype.limited_generalize rv) params; limited_generalize rv typ; (* Check the abbreviation for the object type *) let (obj_params', obj_type) = Ctype.instance_class params typ in let constr = Ctype.newconstr (Path.Pident obj_id) obj_params in begin let ty = Ctype.self_type obj_type in Ctype.hide_private_methods ty; Ctype.close_object ty; begin try List.iter2 (Ctype.unify env) obj_params obj_params' with Ctype.Unify _ -> raise(Error(cl.pci_loc, env, Bad_parameters (obj_id, constr, Ctype.newconstr (Path.Pident obj_id) obj_params'))) end; begin try Ctype.unify env ty constr with Ctype.Unify _ -> raise(Error(cl.pci_loc, env, Abbrev_type_clash (constr, ty, Ctype.expand_head env constr))) end end; (* Check the other temporary abbreviation (#-type) *) begin let (cl_params', cl_type) = Ctype.instance_class params typ in let ty = Ctype.self_type cl_type in Ctype.hide_private_methods ty; Ctype.set_object_name obj_id (Ctype.row_variable ty) cl_params ty; begin try List.iter2 (Ctype.unify env) cl_params cl_params' with Ctype.Unify _ -> raise(Error(cl.pci_loc, env, Bad_parameters (cl_id, Ctype.newconstr (Path.Pident cl_id) cl_params, Ctype.newconstr (Path.Pident cl_id) cl_params'))) end; begin try Ctype.unify env ty cl_ty with Ctype.Unify _ -> let constr = Ctype.newconstr (Path.Pident cl_id) params in raise(Error(cl.pci_loc, env, Abbrev_type_clash (constr, ty, cl_ty))) end end; (* Type of the class constructor *) begin try Ctype.unify env (constructor_type constr obj_type) (Ctype.instance env constr_type) with Ctype.Unify trace -> raise(Error(cl.pci_loc, env, Constructor_type_mismatch (cl.pci_name.txt, trace))) end; (* Class and class type temporary definitions *) let cty_variance = List.map (fun _ -> true, true) params in let cltydef = {clty_params = params; clty_type = class_body typ; clty_variance = cty_variance; clty_path = Path.Pident obj_id} and clty = {cty_params = params; cty_type = typ; cty_variance = cty_variance; cty_path = Path.Pident obj_id; cty_new = match cl.pci_virt with Virtual -> None | Concrete -> Some constr_type} in dummy_class.cty_type <- typ; let env = Env.add_cltype ty_id cltydef ( if define_class then Env.add_class id clty env else env) in if cl.pci_virt = Concrete then begin let sign = Ctype.signature_of_class_type typ in let mets = virtual_methods sign in let vals = Vars.fold (fun name (mut, vr, ty) l -> if vr = Virtual then name :: l else l) sign.cty_vars [] in if mets <> [] || vals <> [] then raise(Error(cl.pci_loc, env, Virtual_class(true, mets, vals))); end; (* Misc. *) let arity = Ctype.class_type_arity typ in let pub_meths = let (fields, _) = Ctype.flatten_fields (Ctype.object_fields (Ctype.expand_head env obj_ty)) in List.map (function (lab, _, _) -> lab) fields in (* Final definitions *) let (params', typ') = Ctype.instance_class params typ in let cltydef = {clty_params = params'; clty_type = class_body typ'; clty_variance = cty_variance; clty_path = Path.Pident obj_id} and clty = {cty_params = params'; cty_type = typ'; cty_variance = cty_variance; cty_path = Path.Pident obj_id; cty_new = match cl.pci_virt with Virtual -> None | Concrete -> Some (Ctype.instance env constr_type)} in let obj_abbr = {type_params = obj_params; type_arity = List.length obj_params; type_kind = Type_abstract; type_private = Public; type_manifest = Some obj_ty; type_variance = List.map (fun _ -> true, true, true) obj_params; type_newtype_level = None; type_loc = cl.pci_loc} in let (cl_params, cl_ty) = Ctype.instance_parameterized_type params (Ctype.self_type typ) in Ctype.hide_private_methods cl_ty; Ctype.set_object_name obj_id (Ctype.row_variable cl_ty) cl_params cl_ty; let cl_abbr = {type_params = cl_params; type_arity = List.length cl_params; type_kind = Type_abstract; type_private = Public; type_manifest = Some cl_ty; type_variance = List.map (fun _ -> true, true, true) cl_params; type_newtype_level = None; type_loc = cl.pci_loc} in ((cl, id, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, List.rev !coercion_locs, expr) :: res, env) let final_decl env define_class (cl, id, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coe, expr) = begin try Ctype.collapse_conj_params env clty.cty_params with Ctype.Unify trace -> raise(Error(cl.pci_loc, env, Non_collapsable_conjunction (id, clty, trace))) end; List.iter Ctype.generalize clty.cty_params; generalize_class_type clty.cty_type; begin match clty.cty_new with None -> () | Some ty -> Ctype.generalize ty end; List.iter Ctype.generalize obj_abbr.type_params; begin match obj_abbr.type_manifest with None -> () | Some ty -> Ctype.generalize ty end; List.iter Ctype.generalize cl_abbr.type_params; begin match cl_abbr.type_manifest with None -> () | Some ty -> Ctype.generalize ty end; if not (closed_class clty) then raise(Error(cl.pci_loc, env, Non_generalizable_class (id, clty))); begin match Ctype.closed_class clty.cty_params (Ctype.signature_of_class_type clty.cty_type) with None -> () | Some reason -> let printer = if define_class then function ppf -> Printtyp.class_declaration id ppf clty else function ppf -> Printtyp.cltype_declaration id ppf cltydef in raise(Error(cl.pci_loc, env, Unbound_type_var(printer, reason))) end; (id, cl.pci_name, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coe, expr, { ci_variance = cl.pci_variance; ci_loc = cl.pci_loc; ci_virt = cl.pci_virt; ci_params = cl.pci_params; (* TODO : check that we have the correct use of identifiers *) ci_id_name = cl.pci_name; ci_id_class = id; ci_id_class_type = ty_id; ci_id_object = obj_id; ci_id_typesharp = cl_id; ci_expr = expr; ci_decl = clty; ci_type_decl = cltydef; }) (* (cl.pci_variance, cl.pci_loc)) *) let extract_type_decls (id, id_loc, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coe, expr, required) decls = (obj_id, obj_abbr, cl_abbr, clty, cltydef, required) :: decls let merge_type_decls (id, id_loc, _clty, ty_id, _cltydef, obj_id, _obj_abbr, cl_id, _cl_abbr, arity, pub_meths, coe, expr, req) (obj_abbr, cl_abbr, clty, cltydef) = (id, id_loc, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coe, expr, req) let final_env define_class env (id, id_loc, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coe, expr, req) = (* Add definitions after cleaning them *) Env.add_type obj_id (Subst.type_declaration Subst.identity obj_abbr) ( Env.add_type cl_id (Subst.type_declaration Subst.identity cl_abbr) ( Env.add_cltype ty_id (Subst.cltype_declaration Subst.identity cltydef) ( if define_class then Env.add_class id (Subst.class_declaration Subst.identity clty) env else env))) (* Check that #c is coercible to c if there is a self-coercion *) let check_coercions env (id, id_loc, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, coercion_locs, expr, req) = begin match coercion_locs with [] -> () | loc :: _ -> let cl_ty, obj_ty = match cl_abbr.type_manifest, obj_abbr.type_manifest with Some cl_ab, Some obj_ab -> let cl_params, cl_ty = Ctype.instance_parameterized_type cl_abbr.type_params cl_ab and obj_params, obj_ty = Ctype.instance_parameterized_type obj_abbr.type_params obj_ab in List.iter2 (Ctype.unify env) cl_params obj_params; cl_ty, obj_ty | _ -> assert false in begin try Ctype.subtype env cl_ty obj_ty () with Ctype.Subtype (tr1, tr2) -> raise(Typecore.Error(loc, env, Typecore.Not_subtype(tr1, tr2))) end; if not (Ctype.opened_object cl_ty) then raise(Error(loc, env, Cannot_coerce_self obj_ty)) end; (id, id_loc, clty, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, arity, pub_meths, req) (*******************************) let type_classes define_class approx kind env cls = let cls = List.map (function cl -> (cl, Ident.create cl.pci_name.txt, Ident.create cl.pci_name.txt, Ident.create cl.pci_name.txt, Ident.create ("#" ^ cl.pci_name.txt))) cls in Ctype.init_def (Ident.current_time ()); Ctype.begin_class_def (); let (res, env) = List.fold_left (initial_env define_class approx) ([], env) cls in let (res, env) = List.fold_right (class_infos define_class kind) res ([], env) in Ctype.end_def (); let res = List.rev_map (final_decl env define_class) res in let decls = List.fold_right extract_type_decls res [] in let decls = Typedecl.compute_variance_decls env decls in let res = List.map2 merge_type_decls res decls in let env = List.fold_left (final_env define_class) env res in let res = List.map (check_coercions env) res in (res, env) let class_num = ref 0 let class_declaration env sexpr = incr class_num; let expr = class_expr (string_of_int !class_num) env env sexpr in (expr, expr.cl_type) let class_description env sexpr = let expr = class_type env sexpr in (expr, expr.cltyp_type) let class_declarations env cls = type_classes true approx_declaration class_declaration env cls let class_descriptions env cls = type_classes true approx_description class_description env cls let class_type_declarations env cls = let (decl, env) = type_classes false approx_description class_description env cls in (List.map (function (_, id_loc, _, ty_id, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, _, _, ci) -> (ty_id, id_loc, cltydef, obj_id, obj_abbr, cl_id, cl_abbr, ci)) decl, env) let rec unify_parents env ty cl = match cl.cl_desc with Tcl_ident (p, _, _) -> begin try let decl = Env.find_class p env in let _, body = Ctype.find_cltype_for_path env decl.cty_path in Ctype.unify env ty (Ctype.instance env body) with Not_found -> () | exn -> assert false end | Tcl_structure st -> unify_parents_struct env ty st | Tcl_fun (_, _, _, cl, _) | Tcl_apply (cl, _) | Tcl_let (_, _, _, cl) | Tcl_constraint (cl, _, _, _, _) -> unify_parents env ty cl and unify_parents_struct env ty st = List.iter (function {cf_desc = Tcf_inher (_, cl, _, _, _)} -> unify_parents env ty cl | _ -> ()) st.cstr_fields let type_object env loc s = incr class_num; let (desc, sign) = class_structure (string_of_int !class_num) true env env loc s in let sty = Ctype.expand_head env sign.cty_self in Ctype.hide_private_methods sty; let (fields, _) = Ctype.flatten_fields (Ctype.object_fields sty) in let meths = List.map (fun (s,_,_) -> s) fields in unify_parents_struct env sign.cty_self desc; (desc, sign, meths) let () = Typecore.type_object := type_object (*******************************) (* Approximate the class declaration as class ['params] id = object end *) let approx_class sdecl = let self' = { ptyp_desc = Ptyp_any; ptyp_loc = Location.none } in let clty' = { pcty_desc = Pcty_signature { pcsig_self = self'; pcsig_fields = []; pcsig_loc = Location.none }; pcty_loc = sdecl.pci_expr.pcty_loc } in { sdecl with pci_expr = clty' } let approx_class_declarations env sdecls = fst (class_type_declarations env (List.map approx_class sdecls)) (*******************************) (* Error report *) open Format let report_error env ppf = function | Repeated_parameter -> fprintf ppf "A type parameter occurs several times" | Unconsistent_constraint trace -> fprintf ppf "The class constraints are not consistent.@."; Printtyp.report_unification_error ppf env trace (fun ppf -> fprintf ppf "Type") (fun ppf -> fprintf ppf "is not compatible with type") | Field_type_mismatch (k, m, trace) -> Printtyp.report_unification_error ppf env trace (function ppf -> fprintf ppf "The %s %s@ has type" k m) (function ppf -> fprintf ppf "but is expected to have type") | Structure_expected clty -> fprintf ppf "@[This class expression is not a class structure; it has type@ %a@]" Printtyp.class_type clty | Cannot_apply clty -> fprintf ppf "This class expression is not a class function, it cannot be applied" | Apply_wrong_label l -> let mark_label = function | "" -> "out label" | l -> sprintf " label ~%s" l in fprintf ppf "This argument cannot be applied with%s" (mark_label l) | Pattern_type_clash ty -> (* XXX Trace *) (* XXX Revoir message d'erreur *) Printtyp.reset_and_mark_loops ty; fprintf ppf "@[%s@ %a@]" "This pattern cannot match self: it only matches values of type" Printtyp.type_expr ty | Unbound_class_2 cl -> fprintf ppf "@[The class@ %a@ is not yet completely defined@]" Printtyp.longident cl | Unbound_class_type_2 cl -> fprintf ppf "@[The class type@ %a@ is not yet completely defined@]" Printtyp.longident cl | Abbrev_type_clash (abbrev, actual, expected) -> (* XXX Afficher une trace ? *) Printtyp.reset_and_mark_loops_list [abbrev; actual; expected]; fprintf ppf "@[The abbreviation@ %a@ expands to type@ %a@ \ but is used with type@ %a@]" Printtyp.type_expr abbrev Printtyp.type_expr actual Printtyp.type_expr expected | Constructor_type_mismatch (c, trace) -> Printtyp.report_unification_error ppf env trace (function ppf -> fprintf ppf "The expression \"new %s\" has type" c) (function ppf -> fprintf ppf "but is used with type") | Virtual_class (cl, mets, vals) -> let print_mets ppf mets = List.iter (function met -> fprintf ppf "@ %s" met) mets in let cl_mark = if cl then "" else " type" in let missings = match mets, vals with [], _ -> "variables" | _, [] -> "methods" | _ -> "methods and variables" in fprintf ppf "@[This class%s should be virtual.@ \ @[<2>The following %s are undefined :%a@]@]" cl_mark missings print_mets (mets @ vals) | Parameter_arity_mismatch(lid, expected, provided) -> fprintf ppf "@[The class constructor %a@ expects %i type argument(s),@ \ but is here applied to %i type argument(s)@]" Printtyp.longident lid expected provided | Parameter_mismatch trace -> Printtyp.report_unification_error ppf env trace (function ppf -> fprintf ppf "The type parameter") (function ppf -> fprintf ppf "does not meet its constraint: it should be") | Bad_parameters (id, params, cstrs) -> Printtyp.reset_and_mark_loops_list [params; cstrs]; fprintf ppf "@[The abbreviation %a@ is used with parameters@ %a@ \ wich are incompatible with constraints@ %a@]" Printtyp.ident id Printtyp.type_expr params Printtyp.type_expr cstrs | Class_match_failure error -> Includeclass.report_error ppf error | Unbound_val lab -> fprintf ppf "Unbound instance variable %s" lab | Unbound_type_var (printer, reason) -> let print_common ppf kind ty0 real lab ty = let ty1 = if real then ty0 else Btype.newgenty(Tobject(ty0, ref None)) in Printtyp.mark_loops ty1; fprintf ppf "The %s %s@ has type@;<1 2>%a@ where@ %a@ is unbound" kind lab Printtyp.type_expr ty Printtyp.type_expr ty0 in let print_reason ppf = function | Ctype.CC_Method (ty0, real, lab, ty) -> print_common ppf "method" ty0 real lab ty | Ctype.CC_Value (ty0, real, lab, ty) -> print_common ppf "instance variable" ty0 real lab ty in Printtyp.reset (); fprintf ppf "@[@[Some type variables are unbound in this type:@;<1 2>%t@]@ \ @[%a@]@]" printer print_reason reason | Make_nongen_seltype ty -> fprintf ppf "@[@[Self type should not occur in the non-generic type@;<1 2>\ %a@]@,\ It would escape the scope of its class@]" Printtyp.type_scheme ty | Non_generalizable_class (id, clty) -> fprintf ppf "@[The type of this class,@ %a,@ \ contains type variables that cannot be generalized@]" (Printtyp.class_declaration id) clty | Cannot_coerce_self ty -> fprintf ppf "@[The type of self cannot be coerced to@ \ the type of the current class:@ %a.@.\ Some occurrences are contravariant@]" Printtyp.type_scheme ty | Non_collapsable_conjunction (id, clty, trace) -> fprintf ppf "@[The type of this class,@ %a,@ \ contains non-collapsible conjunctive types in constraints@]" (Printtyp.class_declaration id) clty; Printtyp.report_unification_error ppf env trace (fun ppf -> fprintf ppf "Type") (fun ppf -> fprintf ppf "is not compatible with type") | Final_self_clash trace -> Printtyp.report_unification_error ppf env trace (function ppf -> fprintf ppf "This object is expected to have type") (function ppf -> fprintf ppf "but actually has type") | Mutability_mismatch (lab, mut) -> let mut1, mut2 = if mut = Immutable then "mutable", "immutable" else "immutable", "mutable" in fprintf ppf "@[The instance variable is %s;@ it cannot be redefined as %s@]" mut1 mut2 | No_overriding (_, "") -> fprintf ppf "@[This inheritance does not override any method@ %s@]" "instance variable" | No_overriding (kind, name) -> fprintf ppf "@[The %s `%s'@ has no previous definition@]" kind name let report_error env ppf err = Printtyp.wrap_printing_env env (fun () -> report_error env ppf err)