X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/7229064dbf9dfcb873824a6f2a9af0bdb112b550..bf3323c57c0e5964c4ecb4e48a9a96cb055eeb0c:/lisp/novice.el diff --git a/lisp/novice.el b/lisp/novice.el index caddf12074..dfaf0b6c6d 100644 --- a/lisp/novice.el +++ b/lisp/novice.el @@ -1,11 +1,16 @@ -;; Handling of disabled commands ("novice mode") for Emacs. -;; Copyright (C) 1985, 1986, 1987 Free Software Foundation, Inc. +;;; novice.el --- handling of disabled commands ("novice mode") for Emacs + +;; Copyright (C) 1985, 1986, 1987, 1994, 2002, 2003, 2004, +;; 2005 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, @@ -14,56 +19,92 @@ ;; 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: +;; 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. ;; The command is found in this-command ;; and the keys are returned by (this-command-keys). -;;;###autoload (setq disabled-command-hook 'disabled-command-hook) ;;;###autoload -(defun disabled-command-hook (&rest ignore) +(defvar disabled-command-function 'disabled-command-function + "Function to call to handle disabled commands. +If nil, the feature is disabled, i.e., all commands work normally.") + +;;;###autoload +(define-obsolete-variable-alias 'disabled-command-hook 'disabled-command-function "22.1") + +;;;###autoload +(defun disabled-command-function (&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") + (with-output-to-temp-buffer "*Disabled Command*" + (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 "*Disabled Command*" + (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))) + (while (progn (setq char (read-event)) + (or (not (numberp char)) + (not (memq (downcase char) + '(?! ?y ?n ?\ ?\C-g))))) (ding) - (message "Please type y, n or Space: ")))) + (message "Please type y, n, ! or SPC (the space bar): ")))) + (setq char (downcase char)) + (if (= char ?\C-g) + (setq quit-flag t)) + (if (= char ?!) + (setq disabled-command-function 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) @@ -72,38 +113,81 @@ N to do nothing (command remains disabled).")) ;;;###autoload (defun enable-command (command) "Allow COMMAND to be executed without special confirmation from now on. -The user's .emacs file is altered so that this will apply +COMMAND must be a symbol. +This command alters the user's .emacs file so that this will apply 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) "Require special confirmation to execute COMMAND from now on. -The user's .emacs file is altered so that this will apply +COMMAND must be a symbol. +This command alters the user's .emacs file 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)) + (insert "(put '" (symbol-name command) " 'disabled t)\n") + (save-buffer)))) + +(provide 'novice) +;; arch-tag: f83c0f96-497e-4db6-a430-8703716c6dd9 +;;; novice.el ends here