From: Stefano Zacchiroli <zack@upsilon.cc>
Date: Fri, 4 Nov 2005 09:32:33 +0000 (+0000)
Subject: added char functions:
X-Git-Tag: V_0_7_2_3~141
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=7cf9117b7c5f6c322c8b02044f4548fae13d0653;p=helm.git

added char functions:
- is_alpha, is_digit, is_alphanum
added string function:
- tilde_expand
---

diff --git a/helm/ocaml/extlib/hExtlib.ml b/helm/ocaml/extlib/hExtlib.ml
index 052205da8..c09dcf2c1 100644
--- a/helm/ocaml/extlib/hExtlib.ml
+++ b/helm/ocaml/extlib/hExtlib.ml
@@ -89,6 +89,22 @@ let trim_blanks s =
   let left, right = find_left 0, find_right (s_len - 1) in
   String.sub s left (right - left + 1)
 
+(** {2 Char processing} *)
+
+let is_alpha c =
+  let code = Char.code c in 
+  (code >= 65 && code <= 90) || (code >= 97 && code <= 122)
+
+let is_digit c =
+  let code = Char.code c in 
+  code >= 48 && code <= 57
+
+let is_blank c =
+  let code = Char.code c in 
+  code = 9 || code = 10 || code = 13 || code = 32
+
+let is_alphanum c = is_alpha c || is_digit c
+
 (** {2 List processing} *)
 
 let rec list_uniq = function 
@@ -171,6 +187,57 @@ let output_file ~filename ~text =
   let oc = open_out filename in
   output_string oc text;
   close_out oc
+
+let blank_split s =
+  let len = String.length s in
+  let buf = Buffer.create 0 in
+  let rec aux acc i =
+    if i >= len
+    then begin
+      if Buffer.length buf > 0
+      then List.rev (Buffer.contents buf :: acc)
+      else List.rev acc
+    end else begin
+      if is_blank s.[i] then
+        if Buffer.length buf > 0 then begin
+          let s = Buffer.contents buf in
+          Buffer.clear buf;
+          aux (s :: acc) (i + 1)
+        end else
+          aux acc (i + 1)
+      else begin
+        Buffer.add_char buf s.[i];
+        aux acc (i + 1)
+      end
+    end
+  in
+  aux [] 0
+
+  (* Rules: * "~name" -> home dir of "name"
+   * "~" -> value of $HOME if defined, home dir of the current user otherwise *)
+let tilde_expand s =
+  let get_home login = (Unix.getpwnam login).Unix.pw_dir in
+  let expand_one s =
+    let len = String.length s in
+    if len > 0 && s.[0] = '~' then begin
+      let login_len = ref 1 in
+      while !login_len < len && is_alphanum (s.[!login_len]) do
+        incr login_len
+      done;
+      let login = String.sub s 1 (!login_len - 1) in
+      try
+        let home =
+          if login = "" then
+            try Sys.getenv "HOME" with Not_found -> get_home (Unix.getlogin ())
+          else
+            get_home login
+        in
+        home ^ String.sub s !login_len (len - !login_len)
+      with Not_found | Invalid_argument _ -> s
+    end else
+      s
+  in
+  String.concat " " (List.map expand_one (blank_split s))
   
 let find ?(test = fun _ -> true) path = 
   let rec aux acc todo = 
diff --git a/helm/ocaml/extlib/hExtlib.mli b/helm/ocaml/extlib/hExtlib.mli
index 376cb448a..3372975da 100644
--- a/helm/ocaml/extlib/hExtlib.mli
+++ b/helm/ocaml/extlib/hExtlib.mli
@@ -34,6 +34,7 @@ val unopt: 'a option -> 'a  (** @raise Failure *)
 val is_dir: string -> bool  (** @return true if file is a directory *)
 val is_regular: string -> bool  (** @return true if file is a regular file *)
 val mkdir: string -> unit (** create dir and parents. @raise Failure *)
+val tilde_expand: string -> string  (** bash-like (head) tilde expansion *)
 
   (** find all _files_ matching test under a filesystem root *)
 val find: ?test:(string -> bool) -> string -> string list 
@@ -48,6 +49,12 @@ val output_file: filename:string -> text:string -> unit (** other way round *)
 
 val finally: (unit -> unit) -> ('a -> 'b) -> 'a -> 'b
 
+(** {2 Char processing} *)
+
+val is_alpha: char -> bool
+val is_digit: char -> bool
+val is_alphanum: char -> bool (** is_alpha || is_digit *)
+
 (** {2 String processing} *)
 
 val split: ?sep:char -> string -> string list (** @param sep defaults to ' ' *)