pukiwikiのwikiデータのファイル名を読みやすい構造に変換する ref: http://qiita.com/items/25d3ac45603ae1090254

trans_pukiwiki_fnames.ml

(*
  pukiwikiの内部データのファイル名を可読できる名前に変換する
  ls /PUKIWIKIDIR/wiki/*.txt | ocaml trans_pukiwiki_fnames.ml
*)
let outdir = "out/"
let verbose = true

let (|>) x f = f x
let (@@) f x = f x
let (!%) = Printf.sprintf

let rec split_at n xs =
  match (n, xs) with
  | (0, xs) -> ([],xs)
  | (n, []) -> ([], [])
  | (n, x::xs) ->
      let (ys,zs) = split_at (n-1) xs in
      (x::ys, zs)

let rec group n xs =
  match split_at n xs with
  | (ys, []) -> [ys]
  | (ys,zs) -> ys :: group n zs

let implode cs =
  String.concat "" (List.map (String.make 1) cs)

let explode s =
  let rec explode_rec n =
    if n >= String.length s then
      []
    else
      String.get s n :: explode_rec (succ n)
  in
  explode_rec 0

let trans1 cs =
  let hex char =
    match char with
    | '0'..'9' -> int_of_char char - int_of_char '0'
    | 'a'..'f' -> 10 + int_of_char char - int_of_char 'a'
    | 'A'..'F' -> 10 + int_of_char char - int_of_char 'A'
    | _ -> failwith (!%"trans1: %c" char)
  in
  List.map hex cs
  |> List.fold_left (fun x y -> 16*x+y) 0
  |> char_of_int

let trans s =
  String.sub s 0 (String.length s - 4)
  |> explode
  |> group 2
  |> List.map trans1
  |> implode
  |> (fun s -> s ^ ".txt")

let read_lines () =
  let rec iter store =
    try iter (read_line () :: store) with
    | End_of_file -> List.rev store
  in
  iter []

let command s =
  if verbose then print_endline s;
  Sys.command s

let mkdir_p filepath =
  command ("mkdir -p " ^ filepath)

let cp x y =
  command ("cp '"^x^"' '"^y^"'")

let _work path =
  let basename = Filename.basename path in
  let new_path = trans basename in (* 変換後のパス ('/' が含まれる!) *)
  let dstdir = outdir ^ Filename.dirname new_path in
  ignore @@ mkdir_p dstdir;
  ignore @@ cp path (outdir ^"/"^ new_path);
  ()

let work path =
  try _work path with
  | e ->
      prerr_endline ("work error: "^path);
      raise e

let () =
  read_lines ()
  |> List.iter work