Re: Stop fiddling with my preferences

[Fabrice Popineau]

Eli Zaretskii <eliz <at> gnu.org> writes:

> 
> > Date: Sun, 23 Nov 2014 16:35:37 +0100 (CET)
> > From: Roland Lutz <rlutz-ml <at> hedmen.org>
> > 
> > For the past few months, however, each time I upgraded to a new version of 
> > Emacs, something in the behavior changed.
> 
> The time between Emacs releases is not measured in months,
> unfortunately, but in years.
> 
> > I had to figure out each time what it was that caused the change and
> > how to compensate for it.  This usually took me an hour or more
> > since it isn't easily documented and most solutions suggested on the
> > web have unwanted side-effects.
> 
> Changes in user-visible behavior are documented in etc/NEWS, together
> with the description of how to get back old behavior.  If you find
> some change that isn't documented like that, please report that as a
> bug.
> 
> > This sort of behavior changes is common among browsers and proprietary 
> > operating systems, but does this make it appropriate for Emacs?  One of 
> > the reasons I'm using mature software is exactly that I *don't* have to be 
> > worried with each new version that ESC won't stop playing animated GIFs 
> > any more, etc.
> 
> We change user-visible behavior in response to user demand, not
> because Emacs is immature.  User demands and expectations change with
> time, and Emacs cannot stay with old defaults forever.
> 
> > How about a command like (use-defaults VERSION)?
> 
> From the menu bar, click Options->Customize Emacs->New Options, and
> you will be able to see all the options that were added or changed
> since some Emacs version.

Nice command, but fails for me right now with

Wrong type argument: stringp, (flycheck . "0.16")

(emacs-repository-get-version)
"f97a7d9a833044a828e0ce96ae3df600d613b359"

in lisp/cus-edit.el :

  (let (found)
    (mapatoms
     (lambda (symbol)
        (let* ((package-version (get symbol 'custom-package-version))
               (version
                (or (and package-version
                         (customize-package-emacs-version symbol
                                                          package-version))
                    (get symbol 'custom-version))))
         (if version
             (when (customize-version-lessp since-version version)
               (if (or (get symbol 'custom-group)
                       (get symbol 'group-documentation))
                   (push (list symbol 'custom-group) found))
               (if (custom-variable-p symbol)
                   (push (list symbol 'custom-variable) found))
               (if (custom-facep symbol)
                   (push (list symbol 'custom-face) found)))))))

(get symbol 'custom-version)  is not a fail safe value to pass to #'customize-
version-lessp since it returns a cons where you need a string.

The #'customize-version-lessp function tries to compare the former which is the 
package version (say for me, it fails with '(flycheck . "0.16") ) whith the 
latter which is "24.1" (the emacs since-version). This has to be fixed albeit I 
have no idea about the best way to do it.

Fabrice