ocaml/typing/types.ml

162 lines
5.3 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Representation of types and declarations *)
open Misc
open Asttypes
(* Type expressions for the core language *)
type type_expr =
{ mutable desc: type_desc;
mutable level: int }
and type_desc =
Tvar
| Tarrow of type_expr * type_expr
| Ttuple of type_expr list
| Tconstr of Path.t * type_expr list * abbrev_memo ref
| Tobject of type_expr * (Path.t * type_expr list) option ref
| Tfield of string * type_expr * type_expr
| Tnil
| Tlink of type_expr
and abbrev_memo =
Mnil
| Mcons of Path.t * type_expr * abbrev_memo
| Mlink of abbrev_memo ref
(* Value descriptions *)
type value_description =
{ val_type: type_expr; (* Type of the value *)
val_kind: value_kind }
and value_kind =
Val_reg (* Regular value *)
| Val_prim of Primitive.description (* Primitive *)
| Val_ivar of mutable_flag (* Instance variable (mutable ?) *)
| Val_anc of (string * Ident.t) list (* Ancestor *)
(* Constructor descriptions *)
type constructor_description =
{ cstr_res: type_expr; (* Type of the result *)
cstr_args: type_expr list; (* Type of the arguments *)
cstr_arity: int; (* Number of arguments *)
cstr_tag: constructor_tag; (* Tag for heap blocks *)
cstr_consts: int; (* Number of constant constructors *)
cstr_nonconsts: int } (* Number of non-const constructors *)
and constructor_tag =
Cstr_constant of int (* Constant constructor (an int) *)
| Cstr_block of int (* Regular constructor (a block) *)
| Cstr_exception of Path.t (* Exception constructor *)
(* Record label descriptions *)
type label_description =
{ lbl_res: type_expr; (* Type of the result *)
lbl_arg: type_expr; (* Type of the argument *)
lbl_mut: mutable_flag; (* Is this a mutable field? *)
lbl_pos: int; (* Position in block *)
lbl_all: label_description array; (* All the labels in this type *)
lbl_repres: record_representation } (* Representation for this record *)
and record_representation =
Record_regular (* All fields are boxed / tagged *)
| Record_float (* All fields are floats *)
(* Type expressions for classes *)
module OrderedString = struct type t = string let compare = compare end
module Vars = Map.Make(OrderedString)
module Concr = Set.Make(OrderedString)
type class_type =
{ cty_params: type_expr list;
cty_args: type_expr list;
cty_vars: (Asttypes.mutable_flag * type_expr) Vars.t;
cty_self: type_expr;
cty_concr: Concr.t;
mutable cty_new: type_expr option }
(* Type definitions *)
type type_declaration =
{ type_params: type_expr list;
type_arity: int;
type_kind: type_kind;
type_manifest: type_expr option }
and type_kind =
Type_abstract
| Type_variant of (string * type_expr list) list
| Type_record of (string * mutable_flag * type_expr) list
type exception_declaration = type_expr list
(* Type expressions for the module language *)
type module_type =
Tmty_ident of Path.t
| Tmty_signature of signature
| Tmty_functor of Ident.t * module_type * module_type
and signature = signature_item list
and signature_item =
Tsig_value of Ident.t * value_description
| Tsig_type of Ident.t * type_declaration
| Tsig_exception of Ident.t * exception_declaration
| Tsig_module of Ident.t * module_type
| Tsig_modtype of Ident.t * modtype_declaration
| Tsig_class of Ident.t * class_type
and modtype_declaration =
Tmodtype_abstract
| Tmodtype_manifest of module_type
(* Iteration on types *)
let iter_type_expr f ty =
match ty.desc with
Tvar -> ()
| Tarrow (ty1, ty2) -> f ty1; f ty2
| Ttuple l -> List.iter f l
| Tconstr (_, l, _) -> List.iter f l
| Tobject(ty, {contents = Some (_, p)})
-> f ty; List.iter f p
| Tobject (ty, _) -> f ty
| Tfield (_, ty1, ty2) -> f ty1; f ty2
| Tnil -> ()
| Tlink ty -> f ty
(* Memorization of abbreviation expansion *)
(* Must be here rather than in ctype.ml, because used by
Env.save_signature *)
let memo = ref []
(* Contains the list of saved abbreviation expansions. *)
let cleanup_abbrev () =
(* Remove all memorized abbreviation expansions. *)
List.iter (fun abbr -> abbr := Mnil) !memo;
memo := []
let memorize_abbrev mem path v =
(* Memorize the expansion of an abbreviation. *)
mem := Mcons (path, v, !mem);
memo := mem :: !memo