ocaml/stdlib/arg.ml

317 lines
9.9 KiB
OCaml

(***********************************************************************)
(* *)
(* OCaml *)
(* *)
(* 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. *)
(* *)
(***********************************************************************)
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 split s =
let i = String.index s '=' in
let len = String.length s in
String.sub s 0 i, String.sub s (i+1) (len-(i+1))
;;
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) =
if String.length doc > 0 then
match spec with
| Symbol (l, _) ->
bprintf buf " %s %s%s\n" key (make_symlist "{" "|" "}" l) doc
| _ ->
bprintf buf " %s %s\n" key doc
;;
let help_action () = raise (Stop (Unknown "-help"));;
let add_help speclist =
let add1 =
try ignore (assoc3 "-help" speclist); []
with Not_found ->
["-help", Unit help_action, " Display this list of options"]
and add2 =
try ignore (assoc3 "--help" speclist); []
with Not_found ->
["--help", Unit help_action, " Display this list of options"]
in
speclist @ (add1 @ add2)
;;
let usage_b buf speclist errmsg =
bprintf buf "%s\n" errmsg;
List.iter (print_spec buf) (add_help speclist);
;;
let usage_string speclist errmsg =
let b = Buffer.create 200 in
usage_b b speclist errmsg;
Buffer.contents b;
;;
let usage speclist errmsg =
eprintf "%s" (usage_string speclist errmsg);
;;
let current = ref 0;;
let bool_of_string_opt x =
try Some (bool_of_string x)
with Invalid_argument _ -> None
let int_of_string_opt x =
try Some (int_of_string x)
with Failure _ -> None
let float_of_string_opt x =
try Some (float_of_string x)
with Failure _ -> None
let parse_argv_dynamic ?(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 && s.[0] = '-' then begin
let action, follow =
try assoc3 s !speclist, None
with Not_found ->
try
let keyword, arg = split s in
assoc3 keyword !speclist, Some arg
with Not_found -> stop (Unknown s)
in
let no_arg () =
match follow with
| None -> ()
| Some arg -> stop (Wrong (s, arg, "no argument")) in
let get_arg () =
match follow with
| None ->
if !current + 1 < l then argv.(!current + 1)
else stop (Missing s)
| Some arg -> arg
in
let consume_arg () =
match follow with
| None -> incr current
| Some _ -> ()
in
begin try
let rec treat_action = function
| Unit f -> f ();
| Bool f ->
let arg = get_arg () in
begin match bool_of_string_opt arg with
| None -> raise (Stop (Wrong (s, arg, "a boolean")))
| Some s -> f s
end;
consume_arg ();
| Set r -> no_arg (); r := true;
| Clear r -> no_arg (); r := false;
| String f ->
let arg = get_arg () in
f arg;
consume_arg ();
| Symbol (symb, f) ->
let arg = get_arg () in
if List.mem arg symb then begin
f arg;
consume_arg ();
end else begin
raise (Stop (Wrong (s, arg, "one of: "
^ (make_symlist "" " " "" symb))))
end
| Set_string r ->
r := get_arg ();
consume_arg ();
| Int f ->
let arg = get_arg () in
begin match int_of_string_opt arg with
| None -> raise (Stop (Wrong (s, arg, "an integer")))
| Some x -> f x
end;
consume_arg ();
| Set_int r ->
let arg = get_arg () in
begin match int_of_string_opt arg with
| None -> raise (Stop (Wrong (s, arg, "an integer")))
| Some x -> r := x
end;
consume_arg ();
| Float f ->
let arg = get_arg () in
begin match float_of_string_opt arg with
| None -> raise (Stop (Wrong (s, arg, "a float")))
| Some x -> f x
end;
consume_arg ();
| Set_float r ->
let arg = get_arg () in
begin match float_of_string_opt arg with
| None -> raise (Stop (Wrong (s, arg, "a float")))
| Some x -> r := x
end;
consume_arg ();
| Tuple specs ->
List.iter treat_action specs;
| Rest f ->
while !current < l - 1 do
f argv.(!current + 1);
consume_arg ();
done;
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_argv ?(current=current) argv speclist anonfun errmsg =
parse_argv_dynamic ~current:current argv (ref speclist) anonfun errmsg;
;;
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;
;;
let parse_dynamic l f msg =
try
parse_argv_dynamic Sys.argv l f msg;
with
| Bad msg -> eprintf "%s" msg; exit 2;
| Help msg -> printf "%s" msg; exit 0;
;;
let second_word s =
let len = String.length s in
let rec loop n =
if n >= len then len
else if s.[n] = ' ' then loop (n+1)
else n
in
try loop (String.index s ' ')
with Not_found -> len
;;
let max_arg_len cur (kwd, spec, doc) =
match spec with
| Symbol _ -> max cur (String.length kwd)
| _ -> max cur (String.length kwd + second_word doc)
;;
let add_padding len ksd =
match ksd with
| (_, _, "") ->
(* Do not pad undocumented options, so that they still don't show up when
* run through [usage] or [parse]. *)
ksd
| (kwd, (Symbol (l, _) as spec), msg) ->
let cutcol = second_word msg in
let spaces = String.make ((max 0 (len - cutcol)) + 3) ' ' in
(kwd, spec, "\n" ^ spaces ^ msg)
| (kwd, spec, msg) ->
let cutcol = second_word msg in
let kwd_len = String.length kwd in
let diff = len - kwd_len - cutcol in
if diff <= 0 then
(kwd, spec, msg)
else
let spaces = String.make diff ' ' in
let prefix = String.sub msg 0 cutcol in
let suffix = String.sub msg cutcol (String.length msg - cutcol) in
(kwd, spec, prefix ^ spaces ^ suffix)
;;
let align ?(limit=max_int) speclist =
let completed = add_help speclist in
let len = List.fold_left max_arg_len 0 completed in
let len = min len limit in
List.map (add_padding len) completed
;;