ocaml/stdlib/arg.ml

205 lines
7.2 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Damien Doligez, projet Para, 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 GNU Library General Public License, with *)
(* the special exception on linking described in file ../LICENSE. *)
(* *)
(***********************************************************************)
(* $Id$ *)
type key = string
type doc = string
type usage_msg = string
type anon_fun = (string -> unit)
type spec =
| Unit of (unit -> unit) (* Call the function with unit argument *)
| Bool of (bool -> unit) (* Call the function with a bool argument *)
| Set of bool ref (* Set the reference to true *)
| Clear of bool ref (* Set the reference to false *)
| String of (string -> unit) (* Call the function with a string argument *)
| Set_string of string ref (* Set the reference to the string argument *)
| Int of (int -> unit) (* Call the function with an int argument *)
| Set_int of int ref (* Set the reference to the int argument *)
| Float of (float -> unit) (* Call the function with a float argument *)
| Set_float of float ref (* Set the reference to the float argument *)
| Tuple of spec list (* Take several arguments according to the
spec list *)
| Symbol of string list * (string -> unit)
(* Take one of the symbols as argument and
call the function with the symbol. *)
| Rest of (string -> unit) (* Stop interpreting keywords and call the
function with each remaining argument *)
exception Bad of string
exception Help of string
type error =
| Unknown of string
| Wrong of string * string * string (* option, actual, expected *)
| Missing of string
| Message of string
exception Stop of error;; (* used internally *)
open Printf
let rec assoc3 x l =
match l with
| [] -> raise Not_found
| (y1, y2, y3) :: t when y1 = x -> y2
| _ :: t -> assoc3 x t
;;
let make_symlist prefix sep suffix l =
match l with
| [] -> "<none>"
| h::t -> (List.fold_left (fun x y -> x ^ sep ^ y) (prefix ^ h) t) ^ suffix
;;
let print_spec buf (key, spec, doc) =
match spec with
| Symbol (l, _) -> bprintf buf " %s %s %s\n" key (make_symlist "{" "|" "}" l)
doc
| _ -> bprintf buf " %s %s\n" key doc
;;
let usage_b buf speclist errmsg =
bprintf buf "%s\n" errmsg;
List.iter (print_spec buf) speclist;
try ignore (assoc3 "-help" speclist)
with Not_found -> bprintf buf " -help Display this list of options\n";
try ignore (assoc3 "--help" speclist)
with Not_found -> bprintf buf " --help Display this list of options\n";
;;
let usage speclist errmsg =
let b = Buffer.create 200 in
usage_b b speclist errmsg;
eprintf "%s" (Buffer.contents b);
;;
let current = ref 0;;
let parse_argv ?(current=current) argv speclist anonfun errmsg =
let l = Array.length argv in
let b = Buffer.create 200 in
let initpos = !current in
let stop error =
let progname = if initpos < l then argv.(initpos) else "(?)" in
begin match error with
| Unknown "-help" -> ()
| Unknown "--help" -> ()
| Unknown s ->
bprintf b "%s: unknown option `%s'.\n" progname s
| Missing s ->
bprintf b "%s: option `%s' needs an argument.\n" progname s
| Wrong (opt, arg, expected) ->
bprintf b "%s: wrong argument `%s'; option `%s' expects %s.\n"
progname arg opt expected
| Message s ->
bprintf b "%s: %s.\n" progname s
end;
usage_b b speclist errmsg;
if error = Unknown "-help" || error = Unknown "--help"
then raise (Help (Buffer.contents b))
else raise (Bad (Buffer.contents b))
in
incr current;
while !current < l do
let s = argv.(!current) in
if String.length s >= 1 && String.get s 0 = '-' then begin
let action =
try assoc3 s speclist
with Not_found -> stop (Unknown s)
in
begin try
let rec treat_action = function
| Unit f -> f ();
| Bool f ->
let arg = argv.(!current + 1) in
begin try f (bool_of_string arg)
with Invalid_argument "bool_of_string" ->
raise (Stop (Wrong (s, arg, "a boolean")))
end;
incr current;
| Set r -> r := true;
| Clear r -> r := false;
| String f when !current + 1 < l ->
f argv.(!current + 1);
incr current;
| Symbol (symb, f) when !current + 1 < l ->
let arg = argv.(!current + 1) in
if List.mem arg symb then begin
f argv.(!current + 1);
incr current;
end else begin
raise (Stop (Wrong (s, arg, "one of: "
^ (make_symlist "" " " "" symb))))
end
| Set_string r when !current + 1 < l ->
r := argv.(!current + 1);
incr current;
| Int f when !current + 1 < l ->
let arg = argv.(!current + 1) in
begin try f (int_of_string arg)
with Failure "int_of_string" ->
raise (Stop (Wrong (s, arg, "an integer")))
end;
incr current;
| Set_int r when !current + 1 < l ->
let arg = argv.(!current + 1) in
begin try r := (int_of_string arg)
with Failure "int_of_string" ->
raise (Stop (Wrong (s, arg, "an integer")))
end;
incr current;
| Float f when !current + 1 < l ->
let arg = argv.(!current + 1) in
begin try f (float_of_string arg);
with Failure "float_of_string" ->
raise (Stop (Wrong (s, arg, "a float")))
end;
incr current;
| Set_float r when !current + 1 < l ->
let arg = argv.(!current + 1) in
begin try r := (float_of_string arg);
with Failure "float_of_string" ->
raise (Stop (Wrong (s, arg, "a float")))
end;
incr current;
| Tuple specs ->
List.iter treat_action specs;
| Rest f ->
while !current < l - 1 do
f argv.(!current + 1);
incr current;
done;
| _ -> raise (Stop (Missing s))
in
treat_action action
with Bad m -> stop (Message m);
| Stop e -> stop e;
end;
incr current;
end else begin
(try anonfun s with Bad m -> stop (Message m));
incr current;
end;
done;
;;
let parse l f msg =
try
parse_argv Sys.argv l f msg;
with
| Bad msg -> eprintf "%s" msg; exit 2;
| Help msg -> printf "%s" msg; exit 0;
;;