-;; Tab conversion commands for Emacs
-;; Copyright (C) 1985 Free Software Foundation, Inc.
+;;; tabify.el --- tab conversion commands for Emacs
+
+;; Copyright (C) 1985, 1994, 2002, 2003, 2004,
+;; 2005 Free Software Foundation, Inc.
+
+;; Maintainer: FSF
;; This file is part of GNU Emacs.
;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 1, or (at your option)
+;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING. If not, write to
-;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
+
+;;; Commentary:
+
+;; Commands to optimize spaces to tabs or expand tabs to spaces in a region
+;; (`tabify' and `untabify'). The variable tab-width does the obvious.
+;;; Code:
+;;;###autoload
(defun untabify (start end)
"Convert all tabs in region to multiple spaces, preserving columns.
-The variable tab-width controls the action."
+Called non-interactively, the region is specified by arguments
+START and END, rather than by the position of point and mark.
+The variable `tab-width' controls the spacing of tab stops."
(interactive "r")
(save-excursion
(save-restriction
- (narrow-to-region start end)
+ (narrow-to-region (point-min) end)
(goto-char start)
(while (search-forward "\t" nil t) ; faster than re-search
- (let ((start (point))
- (column (current-column))
- (indent-tabs-mode nil))
- (skip-chars-backward "\t")
- (delete-region start (point))
+ (forward-char -1)
+ (let ((tab-beg (point))
+ (indent-tabs-mode nil)
+ column)
+ (skip-chars-forward "\t")
+ (setq column (current-column))
+ (delete-region tab-beg (point))
(indent-to column))))))
+(defvar tabify-regexp "[ \t][ \t]+"
+ "Regexp matching whitespace that tabify should consider.
+Usually this will be \"[ \\t][ \\t]+\" to match two or more spaces or tabs.
+\"^[ \\t]+\" is also useful, for tabifying only initial whitespace.")
+
+;;;###autoload
(defun tabify (start end)
"Convert multiple spaces in region to tabs when possible.
A group of spaces is partially replaced by tabs
when this can be done without changing the column they end at.
-The variable tab-width controls the action."
+Called non-interactively, the region is specified by arguments
+START and END, rather than by the position of point and mark.
+The variable `tab-width' controls the spacing of tab stops."
(interactive "r")
(save-excursion
(save-restriction
- (narrow-to-region start end)
+ ;; Include the beginning of the line in the narrowing
+ ;; since otherwise it will throw off current-column.
+ (goto-char start)
+ (beginning-of-line)
+ (narrow-to-region (point) end)
(goto-char start)
- (while (re-search-forward "[ \t][ \t][ \t]*" nil t)
+ (while (re-search-forward tabify-regexp nil t)
(let ((column (current-column))
(indent-tabs-mode t))
(delete-region (match-beginning 0) (point))
(indent-to column))))))
+
+(provide 'tabify)
+
+;;; arch-tag: c83893b1-e0cc-4e57-8a09-73fd03466416
+;;; tabify.el ends here