-;;; novice.el --- handling of disabled commands ("novice mode") for Emacs.
+;;; novice.el --- handling of disabled commands ("novice mode") for Emacs
-;; Copyright (C) 1985, 1986, 1987 Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1986, 1987, 1994, 2002 Free Software Foundation, Inc.
+
+;; Maintainer: FSF
+;; Keywords: internal, help
;; 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., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+
+;; This mode provides a hook which is, by default, attached to various
+;; putatively dangerous commands in a (probably futile) attempt to
+;; prevent lusers from shooting themselves in the feet.
+;;; Code:
;; This function is called (by autoloading)
;; to handle any disabled command.
;; and the keys are returned by (this-command-keys).
;;;###autoload
-(setq disabled-command-hook 'disabled-command-hook)
+(defvar disabled-command-hook 'disabled-command-hook
+ "Function to call to handle disabled commands.
+If nil, the feature is disabled, i.e., all commands work normally.")
;;;###autoload
(defun disabled-command-hook (&rest ignore)
(let (char)
(save-window-excursion
(with-output-to-temp-buffer "*Help*"
- (if (= (aref (this-command-keys) 0) ?\M-x)
- (princ "You have invoked the disabled command ")
- (princ "You have typed ")
- (princ (key-description (this-command-keys)))
- (princ ", invoking disabled command "))
- (princ this-command)
- (princ ":\n")
+ (let ((keys (this-command-keys)))
+ (if (or (eq (aref keys 0)
+ (if (stringp keys)
+ (aref "\M-x" 0)
+ ?\M-x))
+ (and (>= (length keys) 2)
+ (eq (aref keys 0) meta-prefix-char)
+ (eq (aref keys 1) ?x)))
+ (princ (format "You have invoked the disabled command %s.\n"
+ (symbol-name this-command)))
+ (princ (format "You have typed %s, invoking disabled command %s.\n"
+ (key-description keys) (symbol-name this-command)))))
;; Print any special message saying why the command is disabled.
(if (stringp (get this-command 'disabled))
- (princ (get this-command 'disabled)))
- (princ (or (condition-case ()
- (documentation this-command)
- (error nil))
- "<< not documented >>"))
- ;; Keep only the first paragraph of the documentation.
- (save-excursion
- (set-buffer "*Help*")
- (goto-char (point-min))
- (if (search-forward "\n\n" nil t)
- (delete-region (1- (point)) (point-max))
- (goto-char (point-max))))
- (princ "\n\n")
+ (princ (get this-command 'disabled))
+ (princ "It is disabled because new users often find it confusing.\n")
+ (princ "Here's the first part of its description:\n\n")
+ ;; Keep only the first paragraph of the documentation.
+ (with-current-buffer "*Help*"
+ (goto-char (point-max))
+ (let ((start (point)))
+ (save-excursion
+ (princ (or (condition-case ()
+ (documentation this-command)
+ (error nil))
+ "<< not documented >>")))
+ (if (search-forward "\n\n" nil t)
+ (delete-region (match-beginning 0) (point-max)))
+ (goto-char (point-max))
+ (indent-rigidly start (point) 3))))
+ (princ "\n\nDo you want to use this command anyway?\n\n")
(princ "You can now type
-Space to try the command just this once,
- but leave it disabled,
-Y to try it and enable it (no questions if you use it again),
-N to do nothing (command remains disabled)."))
- (message "Type y, n or Space: ")
+y to try it and enable it (no questions if you use it again).
+n to cancel--don't try the command, and it remains disabled.
+SPC to try the command just this once, but leave it disabled.
+! to try it, and enable all disabled commands for this session only.")
+ (save-excursion
+ (set-buffer standard-output)
+ (help-mode)))
+ (message "Type y, n, ! or SPC (the space bar): ")
(let ((cursor-in-echo-area t))
(while (not (memq (setq char (downcase (read-char)))
- '(? ?y ?n)))
+ '(?! ? ?y ?n)))
(ding)
- (message "Please type y, n or Space: "))))
+ (message "Please type y, n, ! or SPC (the space bar): "))))
+ (if (= char ?!)
+ (setq disabled-command-hook nil))
(if (= char ?y)
- (if (y-or-n-p "Enable command for future editing sessions also? ")
+ (if (and user-init-file
+ (not (string= "" user-init-file))
+ (y-or-n-p "Enable command for future editing sessions also? "))
(enable-command this-command)
(put this-command 'disabled nil)))
(if (/= char ?n)
to future sessions."
(interactive "CEnable command: ")
(put command 'disabled nil)
- (save-excursion
- (set-buffer (find-file-noselect (substitute-in-file-name "~/.emacs")))
- (goto-char (point-min))
- (if (search-forward (concat "(put '" (symbol-name command) " ") nil t)
- (delete-region
- (progn (beginning-of-line) (point))
- (progn (forward-line 1) (point)))
- ;; Must have been disabled by default.
- (goto-char (point-max))
- (insert "\n(put '" (symbol-name command) " 'disabled nil)\n"))
- (setq foo (buffer-modified-p))
- (save-buffer)))
+ (let ((init-file user-init-file)
+ (default-init-file
+ (if (eq system-type 'ms-dos) "~/_emacs" "~/.emacs")))
+ (when (null init-file)
+ (if (or (file-exists-p default-init-file)
+ (and (eq system-type 'windows-nt)
+ (file-exists-p "~/_emacs")))
+ ;; Started with -q, i.e. the file containing
+ ;; enabled/disabled commands hasn't been read. Saving
+ ;; settings there would overwrite other settings.
+ (error "Saving settings from \"emacs -q\" would overwrite existing customizations"))
+ (setq init-file default-init-file)
+ (if (and (not (file-exists-p init-file))
+ (eq system-type 'windows-nt)
+ (file-exists-p "~/_emacs"))
+ (setq init-file "~/_emacs")))
+ (save-excursion
+ (set-buffer (find-file-noselect
+ (substitute-in-file-name init-file)))
+ (goto-char (point-min))
+ (if (search-forward (concat "(put '" (symbol-name command) " ") nil t)
+ (delete-region
+ (progn (beginning-of-line) (point))
+ (progn (forward-line 1) (point))))
+ ;; Explicitly enable, in case this command is disabled by default
+ ;; or in case the code we deleted was actually a comment.
+ (goto-char (point-max))
+ (insert "\n(put '" (symbol-name command) " 'disabled nil)\n")
+ (save-buffer))))
;;;###autoload
(defun disable-command (command)
The user's .emacs file is altered so that this will apply
to future sessions."
(interactive "CDisable command: ")
+ (if (not (commandp command))
+ (error "Invalid command name `%s'" command))
(put command 'disabled t)
- (save-excursion
- (set-buffer (find-file-noselect (substitute-in-file-name "~/.emacs")))
- (goto-char (point-min))
- (if (search-forward (concat "(put '" (symbol-name command) " ") nil t)
- (delete-region
- (progn (beginning-of-line) (point))
- (progn (forward-line 1) (point))))
- (goto-char (point-max))
- (insert "(put '" (symbol-name command) " 'disabled t)\n")
- (save-buffer)))
+ (let ((init-file user-init-file)
+ (default-init-file
+ (if (eq system-type 'ms-dos) "~/_emacs" "~/.emacs")))
+ (when (null init-file)
+ (if (or (file-exists-p default-init-file)
+ (and (eq system-type 'windows-nt)
+ (file-exists-p "~/_emacs")))
+ ;; Started with -q, i.e. the file containing
+ ;; enabled/disabled commands hasn't been read. Saving
+ ;; settings there would overwrite other settings.
+ (error "Saving settings from \"emacs -q\" would overwrite existing customizations"))
+ (setq init-file default-init-file)
+ (if (and (not (file-exists-p init-file))
+ (eq system-type 'windows-nt)
+ (file-exists-p "~/_emacs"))
+ (setq init-file "~/_emacs")))
+ (save-excursion
+ (set-buffer (find-file-noselect
+ (substitute-in-file-name init-file)))
+ (goto-char (point-min))
+ (if (search-forward (concat "(put '" (symbol-name command) " ") nil t)
+ (delete-region
+ (progn (beginning-of-line) (point))
+ (progn (forward-line 1) (point))))
+ (goto-char (point-max))
+ (insert "\n(put '" (symbol-name command) " 'disabled t)\n")
+ (save-buffer))))
+
+(provide 'novice)
;;; novice.el ends here
HCoop / bpt / emacs.git / blobdiff