(* filter.ml - Don Yang (uguu.org)
   Remove trailing whitespaces.

   05/12/02
                                                                           *)
type line = String of string | EOF;;

let set_input () =
   if Array.length Sys.argv > 1 && Sys.argv.(1) <> "-"
   then open_in Sys.argv.(1)
   else stdin;;

let set_output () =
   if Array.length Sys.argv > 2
   then open_out Sys.argv.(2)
   else stdout;;

let rec loadfile instream =
   match
      (try String (input_line instream) with End_of_file -> EOF)
      with String x -> [x] @ loadfile instream
      | _ -> [];;

let rec rtrim str =
   let len = String.length str in
   if len > 0
   then
      let x = (String.get str (len - 1)) in
      if x == ' ' || x == '\t'
      then rtrim (String.sub str 0 (len - 1))
      else str
   else
      str;;

let filter () =
   let data = loadfile (set_input()) in
   let outstream = set_output() in
      List.iter (fun x -> output_string outstream ((rtrim x) ^ "\n")) data;;

filter();;