(******************************************************************************)

(*  ocaml-fileutils: files and filenames common operations                    *)

(*                                                                            *)

(*  Copyright (C) 2003-2014, Sylvain Le Gall                                  *)

(*                                                                            *)

(*  This library is free software; you can redistribute it and/or modify it   *)

(*  under the terms of the GNU Lesser General Public License as published by  *)

(*  the Free Software Foundation; either version 2.1 of the License, or (at   *)

(*  your option) any later version, with the OCaml static compilation         *)

(*  exception.                                                                *)

(*                                                                            *)

(*  This library 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 file         *)

(*  COPYING for more details.                                                 *)

(*                                                                            *)

(*  You should have received a copy of the GNU Lesser General Public License  *)

(*  along with this library; if not, write to the Free Software Foundation,   *)

(*  Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA             *)

(******************************************************************************)

(** Manipulate path extension

  *)

let get fn =

  let start_pos =

    (String.rindex fn '.') + 1

  in

  let fn_len =

    String.length fn

  in

    if start_pos = fn_len then

      ""

    else

      String.sub fn start_pos (fn_len - start_pos)

let check fn ext =

  try

    (get fn) = ext

  with Not_found ->

    false

let chop fn =

  try

    let end_pos =

      String.rindex fn '.'

    in

      if end_pos = 0 then

        ""

      else

        String.sub fn 0 end_pos

  with Not_found ->

    fn

let add fn ext =

  fn ^ "." ^ ext

let replace fn ext =

  add (chop fn) ext