(* This file is part of our reusable OCaml BRICKS library
   Copyright (C) 2007  Jean-Vincent Loddo

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>. *)


(** Additional features for the standard module Filename. Open this module in order to use the extended version of Filename instead of the standard one. *)


(** Extra definitions. *)

module Extra = struct

(** add_extension_if_absent filename ext append to the string filename the extension ext but only if the filename has no already an extension. This operation just works on strings and doesn't modify anything in the filesystem.

Example:

# add_extension_if_absent "foo" "txt";;
  : string = "foo.txt"

# add_extension_if_absent "foo.c" "txt";;
  : string = "foo.c"
*)

let add_extension_if_absent filename ext =
 try 
  let _ = (Filename.chop_extension filename) in 
  filename                      (* because the filename already has an extension *)
 with _ -> (filename^"."^ext)    (* because the filename has no extension *)
;;


end;; (* module Extra *)


(** Redefinition of module Filename. *)

module Filename = struct
  include Filename;;
  include Extra;;
end;;