ocaml/typing/unused_var.ml

269 lines
8.7 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Damien Doligez, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 2004 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. *)
(* *)
(***********************************************************************)
(* $Id$ *)
open Parsetree
let silent v = String.length v > 0 && v.[0] = '_';;
let add_vars tbl (vll1, vll2) =
let add_var (v, _loc, used) = Hashtbl.add tbl v used in
List.iter add_var vll1;
List.iter add_var vll2;
;;
let rm_vars tbl (vll1, vll2) =
let rm_var (v, _, _) = Hashtbl.remove tbl v in
List.iter rm_var vll1;
List.iter rm_var vll2;
;;
let w_suspicious x = Warnings.Unused_var x;;
let w_strict x = Warnings.Unused_var_strict x;;
let check_rm_vars ppf tbl (vlul_pat, vlul_as) =
let check_rm_var kind (v, loc, used) =
if not !used && not (silent v)
then Location.print_warning loc ppf (kind v);
Hashtbl.remove tbl v;
in
List.iter (check_rm_var w_strict) vlul_pat;
List.iter (check_rm_var w_suspicious) vlul_as;
;;
let check_rm_let ppf tbl vlulpl =
let check_rm_one flag (v, loc, used) =
Hashtbl.remove tbl v;
flag && (silent v || not !used)
in
let warn_var w_kind (v, loc, used) =
if not (silent v) && not !used
then Location.print_warning loc ppf (w_kind v)
in
let check_rm_pat (def, def_as) =
let def_unused = List.fold_left check_rm_one true def in
let all_unused = List.fold_left check_rm_one def_unused def_as in
List.iter (warn_var (if all_unused then w_suspicious else w_strict)) def;
List.iter (warn_var w_suspicious) def_as;
in
List.iter check_rm_pat vlulpl;
;;
let rec get_vars ((vacc, asacc) as acc) p =
match p.ppat_desc with
| Ppat_any -> acc
| Ppat_var v -> ((v, p.ppat_loc, ref false) :: vacc, asacc)
| Ppat_alias (pp, v) ->
get_vars (vacc, ((v, p.ppat_loc, ref false) :: asacc)) pp
| Ppat_constant _ -> acc
| Ppat_tuple pl -> List.fold_left get_vars acc pl
| Ppat_construct (_, po, _, _) -> get_vars_option acc po
| Ppat_variant (_, po) -> get_vars_option acc po
| Ppat_record (ipl, cls, _) ->
List.fold_left (fun a (_, p) -> get_vars a p) acc ipl
| Ppat_array pl -> List.fold_left get_vars acc pl
| Ppat_or (p1, _p2) -> get_vars acc p1
| Ppat_lazy p -> get_vars acc p
| Ppat_constraint (pp, _) -> get_vars acc pp
| Ppat_type _ -> acc
| Ppat_unpack _ -> acc
and get_vars_option acc po =
match po with
| Some p -> get_vars acc p
| None -> acc
;;
let get_pel_vars pel =
List.map (fun (p, _) -> get_vars ([], []) p) pel
;;
let rec structure ppf tbl l =
List.iter (structure_item ppf tbl) l
and structure_item ppf tbl s =
match s.pstr_desc with
| Pstr_eval e -> expression ppf tbl e;
| Pstr_value (recflag, pel) -> let_pel ppf tbl recflag pel None;
| Pstr_primitive _ -> ()
| Pstr_type _ -> ()
| Pstr_exception _ -> ()
| Pstr_exn_rebind _ -> ()
| Pstr_module (_, me) -> module_expr ppf tbl me;
| Pstr_recmodule stml ->
List.iter (fun (_, _, me) -> module_expr ppf tbl me) stml;
| Pstr_modtype _ -> ()
| Pstr_open _ -> ()
| Pstr_class cdl -> List.iter (class_declaration ppf tbl) cdl;
| Pstr_class_type _ -> ()
| Pstr_include _ -> ()
and expression ppf tbl e =
match e.pexp_desc with
| Pexp_ident (Longident.Lident id) ->
begin try (Hashtbl.find tbl id) := true;
with Not_found -> ()
end;
| Pexp_ident _ -> ()
| Pexp_constant _ -> ()
| Pexp_let (recflag, pel, e) ->
let_pel ppf tbl recflag pel (Some (fun ppf tbl -> expression ppf tbl e));
| Pexp_function (_, eo, pel) ->
expression_option ppf tbl eo;
match_pel ppf tbl pel;
| Pexp_apply (e, lel) ->
expression ppf tbl e;
List.iter (fun (_, e) -> expression ppf tbl e) lel;
| Pexp_match (e, pel) ->
expression ppf tbl e;
match_pel ppf tbl pel;
| Pexp_try (e, pel) ->
expression ppf tbl e;
match_pel ppf tbl pel;
| Pexp_tuple el -> List.iter (expression ppf tbl) el;
| Pexp_construct (_, eo, _) -> expression_option ppf tbl eo;
| Pexp_variant (_, eo) -> expression_option ppf tbl eo;
| Pexp_record (iel, eo) ->
List.iter (fun (_, e) -> expression ppf tbl e) iel;
expression_option ppf tbl eo;
| Pexp_field (e, _) -> expression ppf tbl e;
| Pexp_setfield (e1, _, e2) ->
expression ppf tbl e1;
expression ppf tbl e2;
| Pexp_array el -> List.iter (expression ppf tbl) el;
| Pexp_ifthenelse (e1, e2, eo) ->
expression ppf tbl e1;
expression ppf tbl e2;
expression_option ppf tbl eo;
| Pexp_sequence (e1, e2) ->
expression ppf tbl e1;
expression ppf tbl e2;
| Pexp_while (e1, e2) ->
expression ppf tbl e1;
expression ppf tbl e2;
| Pexp_for (id, e1, e2, _, e3) ->
expression ppf tbl e1;
expression ppf tbl e2;
let defined = ([ (id, e.pexp_loc, ref true) ], []) in
add_vars tbl defined;
expression ppf tbl e3;
check_rm_vars ppf tbl defined;
| Pexp_constraint (e, _, _) -> expression ppf tbl e;
| Pexp_when (e1, e2) ->
expression ppf tbl e1;
expression ppf tbl e2;
| Pexp_send (e, _) -> expression ppf tbl e;
| Pexp_new _ -> ()
| Pexp_setinstvar (_, e) -> expression ppf tbl e;
| Pexp_override sel -> List.iter (fun (_, e) -> expression ppf tbl e) sel;
| Pexp_letmodule (_, me, e) ->
module_expr ppf tbl me;
expression ppf tbl e;
| Pexp_assert e -> expression ppf tbl e;
| Pexp_assertfalse -> ()
| Pexp_lazy e -> expression ppf tbl e;
| Pexp_poly (e, _) -> expression ppf tbl e;
| Pexp_object cs -> class_structure ppf tbl cs;
| Pexp_newtype (_, e) -> expression ppf tbl e
| Pexp_pack me -> module_expr ppf tbl me
| Pexp_open (_, e) -> expression ppf tbl e
and expression_option ppf tbl eo =
match eo with
| Some e -> expression ppf tbl e;
| None -> ()
and let_pel ppf tbl recflag pel body =
match recflag with
| Asttypes.Recursive ->
let defined = get_pel_vars pel in
List.iter (add_vars tbl) defined;
List.iter (fun (_, e) -> expression ppf tbl e) pel;
begin match body with
| None ->
List.iter (rm_vars tbl) defined;
| Some f ->
f ppf tbl;
check_rm_let ppf tbl defined;
end;
| _ ->
List.iter (fun (_, e) -> expression ppf tbl e) pel;
begin match body with
| None -> ()
| Some f ->
let defined = get_pel_vars pel in
List.iter (add_vars tbl) defined;
f ppf tbl;
check_rm_let ppf tbl defined;
end;
and match_pel ppf tbl pel =
List.iter (match_pe ppf tbl) pel
and match_pe ppf tbl (p, e) =
let defined = get_vars ([], []) p in
add_vars tbl defined;
expression ppf tbl e;
check_rm_vars ppf tbl defined;
and module_expr ppf tbl me =
match me.pmod_desc with
| Pmod_ident _ -> ()
| Pmod_structure s -> structure ppf tbl s
| Pmod_functor (_, _, me) -> module_expr ppf tbl me
| Pmod_apply (me1, me2) ->
module_expr ppf tbl me1;
module_expr ppf tbl me2;
| Pmod_constraint (me, _) -> module_expr ppf tbl me
| Pmod_unpack (e) -> expression ppf tbl e
and class_declaration ppf tbl cd = class_expr ppf tbl cd.pci_expr
and class_expr ppf tbl ce =
match ce.pcl_desc with
| Pcl_constr _ -> ()
| Pcl_structure cs -> class_structure ppf tbl cs;
| Pcl_fun (_, _, _, ce) -> class_expr ppf tbl ce;
| Pcl_apply (ce, lel) ->
class_expr ppf tbl ce;
List.iter (fun (_, e) -> expression ppf tbl e) lel;
| Pcl_let (recflag, pel, ce) ->
let_pel ppf tbl recflag pel (Some (fun ppf tbl -> class_expr ppf tbl ce));
| Pcl_constraint (ce, _) -> class_expr ppf tbl ce;
and class_structure ppf tbl (p, cfl) =
let defined = get_vars ([], []) p in
add_vars tbl defined;
List.iter (class_field ppf tbl) cfl;
check_rm_vars ppf tbl defined;
and class_field ppf tbl cf =
match cf with
| Pcf_inher (_, ce, _) -> class_expr ppf tbl ce;
| Pcf_val (_, _, _, e, _) -> expression ppf tbl e;
| Pcf_virt _ | Pcf_valvirt _ -> ()
| Pcf_meth (_, _, _, e, _) -> expression ppf tbl e;
| Pcf_cstr _ -> ()
| Pcf_let (recflag, pel, _) -> let_pel ppf tbl recflag pel None;
| Pcf_init e -> expression ppf tbl e;
;;
let warn ppf ast =
if Warnings.is_active (w_suspicious "") || Warnings.is_active (w_strict "")
then begin
let tbl = Hashtbl.create 97 in
structure ppf tbl ast;
end;
ast
;;