[PATCH] Re: Save Options vs. default-input-method

[Per Abrahamsen]

Richard Stallman <address@hidden> writes:

> I can't find any customize-save-all in the sources, and I don't see
> any function which is like customize-save-variable but without setting
> the value.

I meant custom-save-all.  And it wasn't really correct, as
customize-save-variable performs three tasks, it set the variable, it
marks the variable for saving, and it saves all variables and faces
marked for saving.

>     I don't think customize-save-variable should be changed, the Options
>     menu is simply abusing it.  It is not intended for such use.
>
> What use is it intended for?  

Setting a single variable permanently.  The original use was a
function that would prompt the user for his mail address if not
specified, and save it permanently.

It is inefficient for saving multiple variables, since each call to
customize-save-variable also calls custom-save-all, which delete all
face and variable customization from custom-file, and then recreates
it.  That function should only be called once, after all the relevant
options had been marked for saving.

> I think this change in
> customize-save-variable would be logical, and make it both more useful
> and more natural.

A new function 'mark-variable-for-saving' function would be better, as
the old function already is used with its current semantics.

> But I think you are right that it is not the proper method to use for
> this purpose, for the following reason:
>
>     The other would be to fix menu-bar-options-save to do what I suspect
>     it is intended to do, i.e. just save the current values of the options
>     in the options menu.

That issue is really orthogonal, customize-save-variable is only used
for saving the specified items.

> I think it is clear that it should only save the menu bar options,
> so that is the best solution.

OK.  I'd still prefer to set them with customize-set-variable, because
then if you later customize it, it will have the state "set, but not
saved", rather than "changed outside customize".  And it will be
listed by the 'customize-customized' command.

In any case, here is the patch.  OK to commit?

2002-02-05  Per Abrahamsen  <address@hidden>

        * cus-edit.el (mark-variable-for-saving): New function.
        * menu-bar.el (menu-bar-options-save): Rewrote.

Index: lisp/cus-edit.el
===================================================================
RCS file: /cvsroot/emacs//emacs/lisp/cus-edit.el,v
retrieving revision 1.142
diff -c -r1.142 cus-edit.el
*** lisp/cus-edit.el    2 Feb 2002 15:52:36 -0000       1.142
--- lisp/cus-edit.el    5 Feb 2002 16:25:30 -0000
***************
*** 1,6 ****
  ;;; cus-edit.el --- tools for customizing Emacs and Lisp packages
  ;;
! ;; Copyright (C) 1996, 1997, 1999, 2000, 2001 Free Software Foundation, Inc.
  ;;
  ;; Author: Per Abrahamsen <address@hidden>
  ;; Keywords: help, faces
--- 1,6 ----
  ;;; cus-edit.el --- tools for customizing Emacs and Lisp packages
  ;;
! ;; Copyright (C) 1996, 1997, 1999, 2000, 2001, 2002 Free Software Foundation, 
Inc.
  ;;
  ;; Author: Per Abrahamsen <address@hidden>
  ;; Keywords: help, faces
***************
*** 3744,3749 ****
--- 3744,3779 ----
        (set-buffer (find-file-noselect (custom-file))))
        (let ((file-precious-flag t))
        (save-buffer)))))
+ 
+ ;;;###autoload
+ (defun mark-variable-for-saving (symbol)
+   "Mark SYMBOL for later saving.
+ 
+ If the default value of SYMBOL is different from the standard value, 
+ set the 'saved-value' property to a list whose car evaluates to the
+ default value. Otherwise, set it til nil.
+ 
+ To actually save the value, call 'custom-save-all'.
+ 
+ Return non-nil iff the 'saved-value' property actually changed."
+   (let* ((get (or (get symbol 'custom-get) 'default-value))
+        (value (funcall get symbol))
+        (saved (get symbol 'saved-value))
+        (standard (get symbol 'standard-value))
+        (comment (get symbol 'customized-variable-comment)))
+     ;; Save default value iff different from standard value.
+     (if (and standard 
+            (not (condition-case nil
+                     (equal value (eval (car standard)))
+                   (error nil))))
+       (put symbol 'saved-value (list (custom-quote value)))
+       (put symbol 'saved-value nil))
+     ;; Clear customized information (set, but not saved).
+     (put symbol 'customized-value nil)
+     ;; Save any comment that might have been set.
+     (when comment
+       (put symbol 'saved-variable-comment comment))
+     (not (equal saved (get symbol 'saved-value)))))
  
  ;;; The Customize Menu.
  
Index: lisp/menu-bar.el
===================================================================
RCS file: /cvsroot/emacs//emacs/lisp/menu-bar.el,v
retrieving revision 1.194
diff -c -r1.194 menu-bar.el
*** lisp/menu-bar.el    3 Feb 2002 11:28:28 -0000       1.194
--- lisp/menu-bar.el    5 Feb 2002 16:25:34 -0000
***************
*** 545,565 ****
  (defun menu-bar-options-save ()
    "Save current values of Options menu items using Custom."
    (interactive)
!   (dolist (elt '(debug-on-quit debug-on-error auto-compression-mode
!                case-fold-search truncate-lines show-paren-mode
!                transient-mark-mode global-font-lock-mode
!                current-language-environment default-input-method
!                default-frame-alist display-time-mode))
!     (if (default-value elt)
!       (customize-save-variable elt (default-value elt))))
!   (if (memq 'turn-on-auto-fill text-mode-hook)
!       (customize-save-variable 'text-mode-hook
!                              (default-value 'text-mode-hook)))
!   (if (featurep 'saveplace)
!       (customize-save-variable 'save-place (default-value 'save-place)))
!   (if (featurep 'uniquify)
!       (customize-save-variable 'uniquify-buffer-name-style
!                              (default-value 'uniquify-buffer-name-style))))
  
  (define-key menu-bar-options-menu [save]
    '(menu-item "Save Options" menu-bar-options-save
--- 545,574 ----
  (defun menu-bar-options-save ()
    "Save current values of Options menu items using Custom."
    (interactive)
!   (let ((need-save nil))
!     (dolist (elt '(debug-on-quit debug-on-error auto-compression-mode
!                  case-fold-search truncate-lines show-paren-mode
!                  transient-mark-mode global-font-lock-mode
!                  current-language-environment default-input-method
!                  default-frame-alist display-time-mode))
!       (when (mark-variable-for-saving elt)
!       (setq need-save t)))
!     ;; We only want to save text-mode-hook after adding or removing auto fill.
!     (and (or (memq 'turn-on-auto-fill text-mode-hook) ;Added.
!            ;; If it is already saved, it is safe to save.
!            (get 'text-mode-hook 'saved-value)) ;Maybe removed.
!        (mark-variable-for-saving 'text-mode-hook)
!        (setq need-save t))
!     ;; Avoid loading extra libraries.
!     (and (featurep 'saveplace)
!        (mark-variable-for-saving 'save-place)
!        (setq need-save t))
!     (and(featurep 'uniquify)
!       (mark-variable-for-saving 'uniquify-buffer-name-style)
!       (setq need-save t))
!     ;; Save if we changed anything.
!     (when need-save
!       (custom-save-all))))
  
  (define-key menu-bar-options-menu [save]
    '(menu-item "Save Options" menu-bar-options-save