implemented the first bunch of useful functions

[helm.git] / helm / ocaml / extlib / hExtlib.ml

diff --git a/helm/ocaml/extlib/hExtlib.ml b/helm/ocaml/extlib/hExtlib.ml
index 6e1f3564a4759c91c2942d22dd4d20c4dc81e17b..b8bee56568f08d36bb9816bf295f9b2e0649a0db 100644 (file)
--- a/helm/ocaml/extlib/hExtlib.ml
+++ b/helm/ocaml/extlib/hExtlib.ml
@@ -1,4 +1,4 @@
-(* Copyright (C) 2000, HELM Team.
+(* Copyright (C) 2005, HELM Team.
  * 
  * This file is part of HELM, an Hypertextual, Electronic
  * Library of Mathematics, developed at the Computer Science
@@ -54,3 +54,108 @@ let profile =
  else
   function _ -> { profile = fun f x -> f x }
 
+(** {2 Optional values} *)
+
+let map_option f = function None -> None | Some v -> Some (f v)
+let unopt = function None -> failwith "unopt: None" | Some v -> v
+
+(** {2 String processing} *)
+
+let split ?(sep = ' ') s =
+  let pieces = ref [] in
+  let rec aux idx =
+    match (try Some (String.index_from s idx sep) with Not_found -> None) with
+    | Some pos ->
+        pieces := String.sub s idx (pos - idx) :: !pieces;
+        aux (pos + 1)
+    | None -> pieces := String.sub s idx (String.length s - idx) :: !pieces
+  in
+  aux 0;
+  List.rev !pieces
+
+let trim_blanks s =
+  let rec find_left idx =
+    match s.[idx] with
+    | ' ' | '\t' | '\r' | '\n' -> find_left (idx + 1)
+    | _ -> idx
+  in
+  let rec find_right idx =
+    match s.[idx] with
+    | ' ' | '\t' | '\r' | '\n' -> find_right (idx - 1)
+    | _ -> idx
+  in
+  let s_len = String.length s in
+  let left, right = find_left 0, find_right (s_len - 1) in
+  String.sub s left (right - left + 1)
+
+(*   let rex = Pcre.regexp "^\\s*(.*?)\\s*$" in
+  fun s -> (Pcre.extract ~rex s).(1) *)
+
+(** {2 File predicates} *)
+
+let is_dir fname =
+  try
+    (Unix.stat fname).Unix.st_kind = Unix.S_DIR
+  with Unix.Unix_error _ -> false
+
+let is_regular fname =
+  try
+    (Unix.stat fname).Unix.st_kind = Unix.S_REG
+  with Unix.Unix_error _ -> false
+
+let mkdir path =
+  let components = split ~sep:'/' path in
+  let rec aux where = function
+    | [] -> ()
+    | piece::tl -> 
+        let path = where ^ "/" ^ piece in
+        (try
+          Unix.mkdir path 0o755
+        with 
+        | Unix.Unix_error (Unix.EEXIST,_,_) -> ()
+        | Unix.Unix_error (e,_,_) -> 
+            raise 
+              (Failure 
+                ("Unix.mkdir " ^ path ^ " 0o755 :" ^ (Unix.error_message e))));
+        aux path tl
+  in
+  aux "" components
+
+(** {2 Filesystem} *)
+
+let input_file fname =
+  let size = (Unix.stat fname).Unix.st_size in
+  let buf = Buffer.create size in
+  let ic = open_in fname in
+  Buffer.add_channel buf ic size;
+  close_in ic;
+  Buffer.contents buf
+
+let input_all ic =
+  let size = 10240 in
+  let buf = Buffer.create size in
+  let s = String.create size in
+  (try
+    while true do
+      let bytes = input ic s 0 size in
+      if bytes = 0 then raise End_of_file
+      else Buffer.add_substring buf s 0 bytes
+    done
+  with End_of_file -> ());
+  Buffer.contents buf
+
+let output_file ~filename ~text = 
+  let oc = open_out filename in
+  output_string oc text;
+  close_out oc
+
+(** {2 Exception handling} *)
+
+let finally at_end f arg =
+  let res =
+    try f arg
+    with exn -> at_end (); raise exn
+  in
+  at_end ();
+  res
+