ocaml/typing/env.ml

608 lines
19 KiB
OCaml

(***********************************************************************)
(* *)
(* Caml Special Light *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1995 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Environment handling *)
open Format
open Config
open Misc
open Asttypes
open Longident
open Path
open Typedtree
type error =
Not_an_interface of string
| Corrupted_interface of string
| Illegal_renaming of string * string
exception Error of error
type t = {
values: (Path.t * value_description) Ident.tbl;
constrs: constructor_description Ident.tbl;
labels: label_description Ident.tbl;
types: (Path.t * type_declaration) Ident.tbl;
modules: (Path.t * module_type) Ident.tbl;
modtypes: (Path.t * modtype_declaration) Ident.tbl;
components: (Path.t * module_components) Ident.tbl
}
and module_components =
Structure_comps of structure_components
| Functor_comps of functor_components
and structure_components = {
mutable comp_values: (string, (value_description * int)) Tbl.t;
mutable comp_constrs: (string, (constructor_description * int)) Tbl.t;
mutable comp_labels: (string, (label_description * int)) Tbl.t;
mutable comp_types: (string, (type_declaration * int)) Tbl.t;
mutable comp_modules: (string, (module_type * int)) Tbl.t;
mutable comp_modtypes: (string, (modtype_declaration * int)) Tbl.t;
mutable comp_components: (string, (module_components * int)) Tbl.t
}
and functor_components = {
fcomp_param: Ident.t;
fcomp_arg: module_type;
fcomp_res: module_type;
fcomp_env: t
}
let empty = {
values = Ident.empty; constrs = Ident.empty;
labels = Ident.empty; types = Ident.empty;
modules = Ident.empty; modtypes = Ident.empty;
components = Ident.empty }
(* Persistent structure descriptions *)
type pers_struct =
{ ps_name: string;
ps_sig: signature;
ps_comps: module_components }
let persistent_structures =
(Hashtbl.new 17 : (string, pers_struct) Hashtbl.t)
let imported_units = ref ([] : (string * Digest.t) list)
let read_pers_struct modname filename =
let ic = open_in_bin filename in
try
let buffer = String.create (String.length cmi_magic_number) in
really_input ic buffer 0 (String.length cmi_magic_number);
if buffer <> cmi_magic_number then begin
close_in ic;
raise(Error(Not_an_interface filename))
end;
let ps = (input_value ic : pers_struct) in
let crc = Digest.input ic in
close_in ic;
if ps.ps_name <> modname then
raise(Error(Illegal_renaming(modname, filename)));
(ps, crc)
with End_of_file | Failure _ ->
close_in ic;
raise(Error(Corrupted_interface(filename)))
let find_pers_struct name =
try
Hashtbl.find persistent_structures name
with Not_found ->
let (ps, crc) =
read_pers_struct name
(find_in_path !load_path (lowercase name ^ ".cmi")) in
Hashtbl.add persistent_structures name ps;
imported_units := (name, crc) :: !imported_units;
ps
let reset_cache() =
Hashtbl.clear persistent_structures;
imported_units := []
(* Forward declarations *)
let components_of_functor_appl =
ref ((fun f p1 p2 -> fatal_error "Env.components_of_functor_appl") :
functor_components -> Path.t -> Path.t -> module_components)
let check_modtype_inclusion =
(* to be filled with includemod.check_modtype_inclusion *)
ref ((fun env mty1 mty2 -> fatal_error "Env.include_modtypes") :
t -> module_type -> module_type -> unit)
(* Lookup by identifier *)
let rec find_module_descr path env =
match path with
Pident id ->
begin try
let (p, desc) = Ident.find_same id env.components
in desc
with Not_found ->
if Ident.persistent id
then (find_pers_struct (Ident.name id)).ps_comps
else raise Not_found
end
| Pdot(p, s, pos) ->
begin match find_module_descr p env with
Structure_comps c ->
let (descr, pos) = Tbl.find s c.comp_components in
descr
| Functor_comps f ->
raise Not_found
end
| Papply(p1, p2) ->
begin match find_module_descr p1 env with
Functor_comps f ->
!components_of_functor_appl f p1 p2
| Structure_comps c ->
raise Not_found
end
let find proj1 proj2 path env =
match path with
Pident id ->
let (p, data) = Ident.find_same id (proj1 env)
in data
| Pdot(p, s, pos) ->
begin match find_module_descr p env with
Structure_comps c ->
let (data, pos) = Tbl.find s (proj2 c) in data
| Functor_comps f ->
raise Not_found
end
| Papply(p1, p2) ->
raise Not_found
let find_value = find (fun env -> env.values) (fun sc -> sc.comp_values)
and find_type = find (fun env -> env.types) (fun sc -> sc.comp_types)
and find_modtype = find (fun env -> env.modtypes) (fun sc -> sc.comp_modtypes)
(* Lookup by name *)
let rec lookup_module_descr lid env =
match lid with
Lident s ->
begin try
Ident.find_name s env.components
with Not_found ->
(Pident(Ident.new_persistent s), (find_pers_struct s).ps_comps)
end
| Ldot(l, s) ->
let (p, descr) = lookup_module_descr l env in
begin match descr with
Structure_comps c ->
let (descr, pos) = Tbl.find s c.comp_components in
(Pdot(p, s, pos), descr)
| Functor_comps f ->
raise Not_found
end
| Lapply(l1, l2) ->
let (p1, desc1) = lookup_module_descr l1 env in
let (p2, mty2) = lookup_module l2 env in
begin match desc1 with
Functor_comps f ->
!check_modtype_inclusion env mty2 f.fcomp_arg;
(Papply(p1, p2), !components_of_functor_appl f p1 p2)
| Structure_comps c ->
raise Not_found
end
and lookup_module lid env =
match lid with
Lident s ->
begin try
Ident.find_name s env.modules
with Not_found ->
(Pident(Ident.new_persistent s),
Tmty_signature(find_pers_struct s).ps_sig)
end
| Ldot(l, s) ->
let (p, descr) = lookup_module_descr l env in
begin match descr with
Structure_comps c ->
let (data, pos) = Tbl.find s c.comp_modules in
(Pdot(p, s, pos), data)
| Functor_comps f ->
raise Not_found
end
| Lapply(l1, l2) ->
let (p1, desc1) = lookup_module_descr l1 env in
let (p2, mty2) = lookup_module l2 env in
let p = Papply(p1, p2) in
begin match desc1 with
Functor_comps f ->
!check_modtype_inclusion env mty2 f.fcomp_arg;
(p, Subst.modtype (Subst.add_module f.fcomp_param p2 Subst.identity)
f.fcomp_res)
| Structure_comps c ->
raise Not_found
end
let lookup proj1 proj2 lid env =
match lid with
Lident s ->
Ident.find_name s (proj1 env)
| Ldot(l, s) ->
begin match lookup_module_descr l env with
(p, Structure_comps c) ->
let (data, pos) = Tbl.find s (proj2 c) in
(Pdot(p, s, pos), data)
| (p, Functor_comps f) ->
raise Not_found
end
| Lapply(l1, l2) ->
raise Not_found
let lookup_simple proj1 proj2 lid env =
match lid with
Lident s ->
Ident.find_name s (proj1 env)
| Ldot(l, s) ->
begin match lookup_module_descr l env with
(p, Structure_comps c) ->
let (data, pos) = Tbl.find s (proj2 c) in
data
| (p, Functor_comps f) ->
raise Not_found
end
| Lapply(l1, l2) ->
raise Not_found
let lookup_value =
lookup (fun env -> env.values) (fun sc -> sc.comp_values)
and lookup_constructor =
lookup_simple (fun env -> env.constrs) (fun sc -> sc.comp_constrs)
and lookup_label =
lookup_simple (fun env -> env.labels) (fun sc -> sc.comp_labels)
and lookup_type =
lookup (fun env -> env.types) (fun sc -> sc.comp_types)
and lookup_modtype =
lookup (fun env -> env.modtypes) (fun sc -> sc.comp_modtypes)
(* Scrape a module type *)
let rec scrape_modtype mty env =
match mty with
Tmty_ident path ->
begin match find_modtype path env with
Tmodtype_manifest mty -> scrape_modtype mty env
| Tmodtype_abstract -> mty
end
| _ -> mty
(* Compute constructor descriptions *)
let constructors_of_type ty_path decl =
match decl.type_kind with
Type_variant cstrs ->
Datarepr.constructor_descrs (Tconstr(ty_path, decl.type_params)) cstrs
| _ -> []
(* Compute label descriptions *)
let labels_of_type ty_path decl =
match decl.type_kind with
Type_record labels ->
Datarepr.label_descrs (Tconstr(ty_path, decl.type_params)) labels
| _ -> []
(* Given a signature and a root path, prefix all idents in the signature
by the root path and build the corresponding substitution. *)
let rec prefix_idents root pos sub = function
[] -> ([], sub)
| Tsig_value(id, decl) :: rem ->
let p = Pdot(root, Ident.name id, pos) in
let nextpos = match decl.val_prim with None -> pos+1 | Some _ -> pos in
let (pl, final_sub) = prefix_idents root nextpos sub rem in
(p::pl, final_sub)
| Tsig_type(id, decl) :: rem ->
let p = Pdot(root, Ident.name id, nopos) in
let (pl, final_sub) =
prefix_idents root pos (Subst.add_type id p sub) rem in
(p::pl, final_sub)
| Tsig_exception(id, decl) :: rem ->
let p = Pdot(root, Ident.name id, pos) in
let (pl, final_sub) = prefix_idents root (pos+1) sub rem in
(p::pl, final_sub)
| Tsig_module(id, mty) :: rem ->
let p = Pdot(root, Ident.name id, pos) in
let (pl, final_sub) =
prefix_idents root (pos+1) (Subst.add_module id p sub) rem in
(p::pl, final_sub)
| Tsig_modtype(id, decl) :: rem ->
let p = Pdot(root, Ident.name id, nopos) in
let (pl, final_sub) =
prefix_idents root pos
(Subst.add_modtype id (Tmty_ident p) sub) rem in
(p::pl, final_sub)
(* Compute structure descriptions *)
let rec components_of_module env sub path mty =
match scrape_modtype mty env with
Tmty_signature sg ->
let c =
{ comp_values = Tbl.empty; comp_constrs = Tbl.empty;
comp_labels = Tbl.empty; comp_types = Tbl.empty;
comp_modules = Tbl.empty; comp_modtypes = Tbl.empty;
comp_components = Tbl.empty } in
let (pl, sub) = prefix_idents path 0 sub sg in
let env = ref env in
let pos = ref 0 in
List.iter2 (fun item path ->
match item with
Tsig_value(id, decl) ->
let decl' = Subst.value_description sub decl in
c.comp_values <-
Tbl.add (Ident.name id) (decl', !pos) c.comp_values;
begin match decl.val_prim with
None -> incr pos | Some _ -> ()
end
| Tsig_type(id, decl) ->
let decl' = Subst.type_declaration sub decl in
c.comp_types <-
Tbl.add (Ident.name id) (decl', nopos) c.comp_types;
List.iter
(fun (name, descr) ->
c.comp_constrs <- Tbl.add name (descr, nopos) c.comp_constrs)
(constructors_of_type path decl');
List.iter
(fun (name, descr) ->
c.comp_labels <- Tbl.add name (descr, nopos) c.comp_labels)
(labels_of_type path decl')
| Tsig_exception(id, decl) ->
let decl' = Subst.exception_declaration sub decl in
let cstr = Datarepr.exception_descr path decl' in
c.comp_constrs <-
Tbl.add (Ident.name id) (cstr, !pos) c.comp_constrs;
incr pos
| Tsig_module(id, mty) ->
let mty' = Subst.modtype sub mty in
c.comp_modules <-
Tbl.add (Ident.name id) (mty', !pos) c.comp_modules;
let comps = components_of_module !env sub path mty in
c.comp_components <-
Tbl.add (Ident.name id) (comps, !pos) c.comp_components;
env := store_components id path comps !env;
incr pos
| Tsig_modtype(id, decl) ->
let decl' = Subst.modtype_declaration sub decl in
c.comp_modtypes <-
Tbl.add (Ident.name id) (decl', nopos) c.comp_modtypes;
env := store_modtype id path decl' !env)
sg pl;
Structure_comps c
| Tmty_functor(param, ty_arg, ty_res) ->
Functor_comps {
fcomp_param = param;
fcomp_arg = Subst.modtype sub ty_arg;
fcomp_res = Subst.modtype sub ty_res;
fcomp_env = env }
| Tmty_ident p ->
Structure_comps {
comp_values = Tbl.empty; comp_constrs = Tbl.empty;
comp_labels = Tbl.empty; comp_types = Tbl.empty;
comp_modules = Tbl.empty; comp_modtypes = Tbl.empty;
comp_components = Tbl.empty }
(* Insertion of bindings by identifier + path *)
and store_value id path decl env =
{ values = Ident.add id (path, decl) env.values;
constrs = env.constrs;
labels = env.labels;
types = env.types;
modules = env.modules;
modtypes = env.modtypes;
components = env.components }
and store_type id path info env =
{ values = env.values;
constrs =
List.fold_right
(fun (name, descr) constrs ->
Ident.add (Ident.new name) descr constrs)
(constructors_of_type path info)
env.constrs;
labels =
List.fold_right
(fun (name, descr) labels ->
Ident.add (Ident.new name) descr labels)
(labels_of_type path info)
env.labels;
types = Ident.add id (path, info) env.types;
modules = env.modules;
modtypes = env.modtypes;
components = env.components }
and store_exception id path decl env =
{ values = env.values;
constrs = Ident.add id (Datarepr.exception_descr path decl) env.constrs;
labels = env.labels;
types = env.types;
modules = env.modules;
modtypes = env.modtypes;
components = env.components }
and store_module id path mty env =
{ values = env.values;
constrs = env.constrs;
labels = env.labels;
types = env.types;
modules = Ident.add id (path, mty) env.modules;
modtypes = env.modtypes;
components =
Ident.add id (path, components_of_module env Subst.identity path mty)
env.components }
and store_modtype id path info env =
{ values = env.values;
constrs = env.constrs;
labels = env.labels;
types = env.types;
modules = env.modules;
modtypes = Ident.add id (path, info) env.modtypes;
components = env.components }
and store_components id path comps env =
{ values = env.values;
constrs = env.constrs;
labels = env.labels;
types = env.types;
modules = env.modules;
modtypes = env.modtypes;
components = Ident.add id (path, comps) env.components }
(* Memoized function to compute the components of a functor application
in a path. *)
let funappl_memo =
(Hashtbl.new 17 : (Path.t, module_components) Hashtbl.t)
let _ =
components_of_functor_appl :=
(fun f p1 p2 ->
let p = Papply(p1, p2) in
try
Hashtbl.find funappl_memo p
with Not_found ->
let mty =
Subst.modtype (Subst.add_module f.fcomp_param p2 Subst.identity)
f.fcomp_res in
let comps = components_of_module f.fcomp_env Subst.identity p mty in
Hashtbl.add funappl_memo p comps;
comps)
(* Insertion of bindings by identifier *)
let add_value id desc env =
store_value id (Pident id) desc env
and add_type id info env =
store_type id (Pident id) info env
and add_exception id decl env =
store_exception id (Pident id) decl env
and add_module id mty env =
store_module id (Pident id) mty env
and add_modtype id info env =
store_modtype id (Pident id) info env
(* Insertion of bindings by name *)
let enter store_fun name data env =
let id = Ident.new name in (id, store_fun id (Pident id) data env)
let enter_value = enter store_value
and enter_type = enter store_type
and enter_exception = enter store_exception
and enter_module = enter store_module
and enter_modtype = enter store_modtype
(* Insertion of all components of a signature *)
let add_signature_component env comp =
match comp with
Tsig_value(id, decl) -> add_value id decl env
| Tsig_type(id, decl) -> add_type id decl env
| Tsig_exception(id, decl) -> add_exception id decl env
| Tsig_module(id, mty) -> add_module id mty env
| Tsig_modtype(id, decl) -> add_modtype id decl env
let add_signature sg env =
List.fold_left add_signature_component env sg
(* Open a signature path *)
let open_signature root sg env =
(* First build the paths and substitution *)
let (pl, sub) = prefix_idents root 0 Subst.identity sg in
(* Then enter the components in the environment after substitution *)
List.fold_left2
(fun env item p ->
match item with
Tsig_value(id, decl) ->
store_value (Ident.hide id) p
(Subst.value_description sub decl) env
| Tsig_type(id, decl) ->
store_type (Ident.hide id) p
(Subst.type_declaration sub decl) env
| Tsig_exception(id, decl) ->
store_exception (Ident.hide id) p
(Subst.exception_declaration sub decl) env
| Tsig_module(id, mty) ->
store_module (Ident.hide id) p (Subst.modtype sub mty) env
| Tsig_modtype(id, decl) ->
store_modtype (Ident.hide id) p
(Subst.modtype_declaration sub decl) env)
env sg pl
(* Open a signature from a file *)
let open_pers_signature name env =
let ps = find_pers_struct name in
open_signature (Pident(Ident.new_persistent name)) ps.ps_sig env
(* Read a signature from a file *)
let read_signature modname filename =
let (ps, crc) = read_pers_struct modname filename in (ps.ps_sig, crc)
(* Save a signature to a file *)
let save_signature sg modname filename =
let ps =
{ ps_name = modname;
ps_sig = sg;
ps_comps =
components_of_module empty Subst.identity
(Pident(Ident.new_persistent modname)) (Tmty_signature sg) } in
let oc = open_out_bin filename in
output_string oc cmi_magic_number;
output_value oc ps;
flush oc;
let crc = Digest.file filename in
Digest.output oc crc;
close_out oc;
crc
(* Make the initial environment *)
let initial = Predef.build_initial_env add_type add_exception empty
(* Return the list of imported interfaces with their CRCs *)
let imported_units() = !imported_units
(* Error report *)
let report_error = function
Not_an_interface filename ->
print_string filename; print_space();
print_string "is not a compiled interface."
| Corrupted_interface filename ->
print_string "Corrupted compiled interface"; print_space();
print_string filename
| Illegal_renaming(modname, filename) ->
print_string filename; print_space();
print_string "contains the compiled interface for"; print_space();
print_string modname