ocaml/typing/includemod.ml

372 lines
13 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Inclusion checks for the module language *)
open Misc
open Path
open Types
open Typedtree
type error =
Missing_field of Ident.t
| Value_descriptions of Ident.t * value_description * value_description
| Type_declarations of Ident.t * type_declaration * type_declaration
| Exception_declarations of
Ident.t * exception_declaration * exception_declaration
| Module_types of module_type * module_type
| Modtype_infos of Ident.t * modtype_declaration * modtype_declaration
| Modtype_permutation
| Interface_mismatch of string * string
| Class_types of Ident.t * class_type * class_type
exception Error of error list
(* All functions "blah env x1 x2" check that x1 is included in x2,
i.e. that x1 is the type of an implementation that fulfills the
specification x2. If not, Error is raised with a backtrace of the error. *)
(* Inclusion between value descriptions *)
let value_descriptions env subst id vd1 vd2 =
let vd2 = Subst.value_description subst vd2 in
try
Includecore.value_descriptions env vd1 vd2
with Includecore.Dont_match ->
raise(Error[Value_descriptions(id, vd1, vd2)])
(* Inclusion between type declarations *)
let type_declarations env subst id decl1 decl2 =
let decl2 = Subst.type_declaration subst decl2 in
if Includecore.type_declarations env id decl1 decl2
then ()
else raise(Error[Type_declarations(id, decl1, decl2)])
(* Inclusion between exception declarations *)
let exception_declarations env subst id decl1 decl2 =
let decl2 = Subst.exception_declaration subst decl2 in
if Includecore.exception_declarations env decl1 decl2
then ()
else raise(Error[Exception_declarations(id, decl1, decl2)])
(* Inclusion between class types *)
let class_types env subst id decl1 decl2 =
let decl2 = Subst.class_type subst decl2 in
if Includecore.class_types env decl1 decl2
then ()
else raise(Error[Class_types(id, decl1, decl2)])
(* Expand a module type identifier when possible *)
exception Dont_match
let expand_module_path env path =
try
Env.find_modtype_expansion path env
with Not_found ->
raise Dont_match
(* Extract name, kind and ident from a signature item *)
type field_desc =
Field_value of string
| Field_type of string
| Field_exception of string
| Field_module of string
| Field_modtype of string
| Field_classtype of string
let item_ident_name = function
Tsig_value(id, _) -> (id, Field_value(Ident.name id))
| Tsig_type(id, _) -> (id, Field_type(Ident.name id))
| Tsig_exception(id, _) -> (id, Field_exception(Ident.name id))
| Tsig_module(id, _) -> (id, Field_module(Ident.name id))
| Tsig_modtype(id, _) -> (id, Field_modtype(Ident.name id))
| Tsig_class(id, _) -> (id, Field_classtype(Ident.name id))
(* Simplify a structure coercion *)
let simplify_structure_coercion cc =
let pos = ref 0 in
try
List.iter
(fun (n, c) ->
if n <> !pos or c <> Tcoerce_none then raise Exit;
incr pos)
cc;
Tcoerce_none
with Exit ->
Tcoerce_structure cc
(* Inclusion between module types.
Return the restriction that transforms a value of the smaller type
into a value of the bigger type. *)
let rec modtypes env subst mty1 mty2 =
try
try_modtypes env subst mty1 mty2
with
Dont_match ->
raise(Error[Module_types(mty1, Subst.modtype subst mty2)])
| Error reasons ->
raise(Error(Module_types(mty1, Subst.modtype subst mty2) :: reasons))
and try_modtypes env subst mty1 mty2 =
match (mty1, mty2) with
(_, Tmty_ident p2) ->
try_modtypes2 env mty1 (Subst.modtype subst mty2)
| (Tmty_ident p1, _) ->
try_modtypes env subst (expand_module_path env p1) mty2
| (Tmty_signature sig1, Tmty_signature sig2) ->
signatures env subst sig1 sig2
| (Tmty_functor(param1, arg1, res1), Tmty_functor(param2, arg2, res2)) ->
let cc_arg =
modtypes env Subst.identity (Subst.modtype subst arg2) arg1
in
let cc_res =
modtypes (Env.add_module param1 arg1 env)
(Subst.add_module param2 (Pident param1) subst) res1 res2
in
begin match (cc_arg, cc_res) with
(Tcoerce_none, Tcoerce_none) -> Tcoerce_none
| _ -> Tcoerce_functor(cc_arg, cc_res)
end
| (_, _) ->
raise Dont_match
and try_modtypes2 env mty1 mty2 =
(* mty2 is an identifier *)
match (mty1, mty2) with
(Tmty_ident p1, Tmty_ident p2) when Path.same p1 p2 ->
Tcoerce_none
| (_, Tmty_ident p2) ->
try_modtypes env Subst.identity mty1 (expand_module_path env p2)
| (_, _) ->
fatal_error "Includemod.try_modtypes2"
(* Inclusion between signatures *)
and signatures env subst sig1 sig2 =
(* Environment used to check inclusion of components *)
let new_env =
Env.add_signature sig1 env in
(* Build a table of the components of sig1, along with their positions.
The table is indexed by kind and name of component *)
let rec build_component_table pos tbl = function
[] -> tbl
| item :: rem ->
let (id, name) = item_ident_name item in
let nextpos =
match item with
Tsig_value(_,{val_kind = Val_prim _})
| Tsig_type(_,_)
| Tsig_modtype(_,_) -> pos
| Tsig_value(_,_)
| Tsig_exception(_,_)
| Tsig_module(_,_)
| Tsig_class(_, _) -> pos+1 in
build_component_table nextpos
(Tbl.add name (id, item, pos) tbl) rem in
let comps1 =
build_component_table 0 Tbl.empty sig1 in
(* Pair each component of sig2 with a component of sig1,
identifying the names along the way.
Return a coercion list indicating, for all run-time components
of sig2, the position of the matching run-time components of sig1
and the coercion to be applied to it. *)
let rec pair_components subst paired unpaired = function
[] ->
begin match unpaired with
[] -> signature_components new_env subst (List.rev paired)
| _ -> raise(Error unpaired)
end
| item2 :: rem ->
let (id2, name2) = item_ident_name item2 in
begin try
let (id1, item1, pos1) = Tbl.find name2 comps1 in
let new_subst =
match item2 with
Tsig_type _ ->
Subst.add_type id2 (Pident id1) subst
| Tsig_module _ ->
Subst.add_module id2 (Pident id1) subst
| Tsig_modtype _ ->
Subst.add_modtype id2 (Tmty_ident (Pident id1)) subst
| Tsig_value _ | Tsig_exception _ | Tsig_class _ ->
subst
in
pair_components new_subst
((item1, item2, pos1) :: paired) unpaired rem
with Not_found ->
pair_components subst paired (Missing_field id2 :: unpaired) rem
end in
(* Do the pairing and checking, and return the final coercion *)
simplify_structure_coercion(pair_components subst [] [] sig2)
(* Inclusion between signature components *)
and signature_components env subst = function
[] -> []
| (Tsig_value(id1, valdecl1), Tsig_value(id2, valdecl2), pos) :: rem ->
let cc = value_descriptions env subst id1 valdecl1 valdecl2 in
begin match valdecl2.val_kind with
Val_prim p -> signature_components env subst rem
| _ -> (pos, cc) :: signature_components env subst rem
end
| (Tsig_type(id1, tydecl1), Tsig_type(id2, tydecl2), pos) :: rem ->
type_declarations env subst id1 tydecl1 tydecl2;
signature_components env subst rem
| (Tsig_exception(id1, excdecl1), Tsig_exception(id2, excdecl2), pos)
:: rem ->
exception_declarations env subst id1 excdecl1 excdecl2;
(pos, Tcoerce_none) :: signature_components env subst rem
| (Tsig_module(id1, mty1), Tsig_module(id2, mty2), pos) :: rem ->
let cc = modtypes env subst mty1 mty2 in
(pos, cc) :: signature_components env subst rem
| (Tsig_modtype(id1, info1), Tsig_modtype(id2, info2), pos) :: rem ->
modtype_infos env subst id1 info1 info2;
signature_components env subst rem
| (Tsig_class(id1, decl1), Tsig_class(id2, decl2), pos) :: rem ->
class_types env subst id1 decl1 decl2;
(pos, Tcoerce_none) :: signature_components env subst rem
| _ ->
fatal_error "Includemod.signature_components"
(* Inclusion between module type specifications *)
and modtype_infos env subst id info1 info2 =
let info2 = Subst.modtype_declaration subst info2 in
try
match (info1, info2) with
(Tmodtype_abstract, Tmodtype_abstract) -> ()
| (Tmodtype_manifest mty1, Tmodtype_abstract) -> ()
| (Tmodtype_manifest mty1, Tmodtype_manifest mty2) ->
check_modtype_equiv env mty1 mty2
| (Tmodtype_abstract, Tmodtype_manifest mty2) ->
check_modtype_equiv env (Tmty_ident(Pident id)) mty2
with Error reasons ->
raise(Error(Modtype_infos(id, info1, info2) :: reasons))
and check_modtype_equiv env mty1 mty2 =
match
(modtypes env Subst.identity mty1 mty2,
modtypes env Subst.identity mty2 mty1)
with
(Tcoerce_none, Tcoerce_none) -> ()
| (_, _) -> raise(Error [Modtype_permutation])
(* Simplified inclusion check between module types *)
let check_modtype_inclusion env mty1 mty2 =
try
modtypes env Subst.identity mty1 mty2; ()
with Error reasons ->
raise Not_found
let _ = Env.check_modtype_inclusion := check_modtype_inclusion
(* Check that an implementation of a compilation unit meets its
interface. *)
let compunit impl_name impl_sig intf_name intf_sig =
try
signatures Env.initial Subst.identity impl_sig intf_sig
with Error reasons ->
raise(Error(Interface_mismatch(impl_name, intf_name) :: reasons))
(* Hide the substitution parameter to the outside world *)
let modtypes env mty1 mty2 = modtypes env Subst.identity mty1 mty2
let signatures env sig1 sig2 = signatures env Subst.identity sig1 sig2
let type_declarations env id decl1 decl2 =
type_declarations env Subst.identity id decl1 decl2
(* Error report *)
open Format
open Printtyp
let include_err = function
Missing_field id ->
print_string "The field `"; ident id;
print_string "' is required but not provided"
| Value_descriptions(id, d1, d2) ->
open_hvbox 2;
print_string "Values do not match:"; print_space();
value_description id d1;
print_break 1 (-2);
print_string "is not included in"; print_space();
value_description id d2;
close_box()
| Type_declarations(id, d1, d2) ->
open_hvbox 2;
print_string "Type declarations do not match:"; print_space();
type_declaration id d1;
print_break 1 (-2);
print_string "is not included in"; print_space();
type_declaration id d2;
close_box()
| Exception_declarations(id, d1, d2) ->
open_hvbox 2;
print_string "Exception declarations do not match:"; print_space();
exception_declaration id d1;
print_break 1 (-2);
print_string "is not included in"; print_space();
exception_declaration id d2;
close_box()
| Module_types(mty1, mty2)->
open_hvbox 2;
print_string "Modules do not match:"; print_space();
modtype mty1;
print_break 1 (-2);
print_string "is not included in"; print_space();
modtype mty2;
close_box()
| Modtype_infos(id, d1, d2) ->
open_hvbox 2;
print_string "Module type declarations do not match:"; print_space();
modtype_declaration id d1;
print_break 1 (-2);
print_string "is not included in"; print_space();
modtype_declaration id d2;
close_box()
| Modtype_permutation ->
print_string "Illegal permutation of structure fields"
| Interface_mismatch(impl_name, intf_name) ->
open_box 0;
print_string "The implementation "; print_string impl_name;
print_space(); print_string "does not match the interface ";
print_string intf_name;
print_string ":";
close_box()
| Class_types(id, d1, d2) ->
open_hvbox 2;
print_string "Class types do not match:"; print_space();
Printtyp.class_type id d1;
print_break 1 (-2);
print_string "is not included in"; print_space();
Printtyp.class_type id d2;
close_box()
let report_error errlist =
match errlist with
[] -> ()
| err :: rem ->
open_vbox 0;
include_err err;
List.iter (fun err -> print_space(); include_err err) rem;
close_box()