(disabled-command-function): Add useful args.

Setup the help buffer so that [back] works.
Remove redundant call to help-mode.
(disabled-command-function): Use `case'.
(en/disable-command): New function extracted from enable-command.
(enable-command, disable-command): Use it.

2 files changed, 53 insertions, 62 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 7f6b73be406..c4dddab05c6 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,12 @@
+2009-11-15  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * novice.el (disabled-command-function): Add useful args.
+        Setup the help buffer so that [back] works.
+        Remove redundant call to help-mode.
+        (disabled-command-function): Use `case'.
+        (en/disable-command): New function extracted from enable-command.
+        (enable-command, disable-command): Use it.
+
 2009-11-14  Glenn Morris  <rgm@gnu.org>
 
         * menu-bar.el (menu-bar-tools-menu): Read and send mail entries are not
diff --git a/lisp/novice.el b/lisp/novice.el
index 963247dc40a..048e796509e 100644
--- a/lisp/novice.el
+++ b/lisp/novice.el
@@ -34,6 +34,8 @@
 ;; The command is found in this-command
 ;; and the keys are returned by (this-command-keys).
 
+(eval-when-compile (require 'cl))
+
 ;;;###autoload
 (defvar disabled-command-function 'disabled-command-function
   "Function to call to handle disabled commands.
@@ -45,11 +47,13 @@ If nil, the feature is disabled, i.e., all commands work normally.")
 ;; It is ok here to assume that this-command is a symbol
 ;; because we won't get called otherwise.
 ;;;###autoload
-(defun disabled-command-function (&rest ignore)
+(defun disabled-command-function (&optional cmd keys)
+  (unless cmd (setq cmd this-command))
+  (unless keys (setq keys (this-command-keys)))
   (let (char)
     (save-window-excursion
-     (with-output-to-temp-buffer "*Disabled Command*"
-       (let ((keys (this-command-keys)))
+      (help-setup-xref (list 'disabled-command-function cmd keys) nil)
+      (with-output-to-temp-buffer "*Disabled Command*" ;; (help-buffer)
          (if (or (eq (aref keys 0)
                      (if (stringp keys)
                          (aref "\M-x" 0)
@@ -57,22 +61,21 @@ If nil, the feature is disabled, i.e., all commands work normally.")
                  (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 invoked the disabled command %s.\n" cmd))
            (princ (format "You have typed %s, invoking disabled command %s.\n"
-                          (key-description keys) (symbol-name this-command)))))
+                         (key-description keys) cmd)))
        ;; Print any special message saying why the command is disabled.
-       (if (stringp (get this-command 'disabled))
-           (princ (get this-command 'disabled))
+        (if (stringp (get cmd 'disabled))
+            (princ (get cmd '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*"
+          (with-current-buffer "*Disabled Command*" ;; standard-output
            (goto-char (point-max))
            (let ((start (point)))
              (save-excursion
                (princ (or (condition-case ()
-                              (documentation this-command)
+                               (documentation cmd)
                             (error nil))
                           "<< not documented >>")))
              (if (search-forward "\n\n" nil t)
@@ -85,8 +88,10 @@ 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.")
-       (with-current-buffer standard-output
-         (help-mode)))
+        ;; Redundant since with-output-to-temp-buffer will do it anyway.
+        ;; (with-current-buffer standard-output
+        ;;   (help-mode))
+        )
      (fit-window-to-buffer (get-buffer-window "*Disabled Command*"))
      (message "Type y, n, ! or SPC (the space bar): ")
      (let ((cursor-in-echo-area t))
@@ -97,31 +102,26 @@ SPC to try the command just this once, but leave it disabled.
          (ding)
          (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)
+    (case char
+     (?\C-g (setq quit-flag t))
+     (?! (setq disabled-command-function nil))
+     (?y
         (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)
-        (call-interactively this-command))))
-
-;;;###autoload
-(defun enable-command (command)
-  "Allow COMMAND to be executed without special confirmation from now on.
-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)
+          (enable-command cmd)
+        (put cmd 'disabled nil)))
+     (?n nil)
+     (t (call-interactively cmd)))))
+
+(defun en/disable-command (command disable)
+  (unless (commandp command)
+    (error "Invalid command name `%s'" command))
+  (put command 'disabled disable)
   (let ((init-file user-init-file)
         (default-init-file
           (if (eq system-type 'ms-dos) "~/_emacs" "~/.emacs")))
-    (when (null init-file)
+    (unless init-file
       (if (or (file-exists-p default-init-file)
               (and (eq system-type 'windows-nt)
                    (file-exists-p "~/_emacs")))
@@ -144,46 +144,28 @@ to future sessions."
       ;; 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")
+      (unless (bolp) (newline))
+      (insert "(put '" (symbol-name command) " 'disabled "
+              (symbol-name disable) ")\n")
       (save-buffer))))
 
 ;;;###autoload
+(defun enable-command (command)
+  "Allow COMMAND to be executed without special confirmation from now on.
+COMMAND must be a symbol.
+This command alters the user's .emacs file so that this will apply
+to future sessions."
+  (interactive "CEnable command: ")
+  (en/disable-command command nil))
+
+;;;###autoload
 (defun disable-command (command)
   "Require special confirmation to execute COMMAND from now on.
 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)
-  (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")))
-    (with-current-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))))
+  (en/disable-command command t))
 
 (provide 'novice)