Re: "CHANGED outside Customize" in frames customization group

[martin rudalics <rudalics@gmx.at>]

 >     IIUC `custom-reevaluate-setting' can be used to set a variable after
 >     some environment value has been established as for `blink-cursor-mode'.
 >     The situation seems completely different for `default-frame-alist'.
 >
 > In what way is it different?

`frame-notice-user-settings' may set the value of `default-frame-alist'
overriding a saved or standard value.  The value of `blink-cursor-mode'
is not reset by Emacs.

 >       The first reason is immediately visible
 >     when starting Emacs without your .emacs.  The value is here:
 >
 >     ((left-fringe) (right-fringe) (menu-bar-lines . 1) (tool-bar-lines . 1))
 >
 >     I know how to get rid of the -fringe entries.
 >
 > ISTR someone recently posted a patch that would affect the handling
 > of fringes in `default-frame-alist'.  Would they get rid of those?

I hope so.

 > 						   But I don't know what to
 >     do with the -line entries (which are BTW already there in Emacs 21).
 >
 > Why does anything need to be done with them?
 > Could you just leave them alone?
 > Or else change the numbers?
 >
 >     Delete them in the customization buffer, save your settings, restart
 >     Emacs, and here they are again.
 >
 > That is arguably a bug, and maybe we should fix it.
 > However, I do not see that this bug is so grave
 > that we should conclude that `default-frame-alist' is
 > unsuitable for use with Custom.

The bug causes the "CHANGED outside Customize ..." state.

 >     A second reason is the function `modify-all-frames-parameters'.  This
 >     function may set `default-frame-alist'.  Customize `tool-bar-mode' or
 >     `fringe-mode' and you will change your `default-frame-alist' settings.
 >
 > I don't see a problem in that.  Why do you think it is a problem?
 > What aspect of it is the problem?

Customizing `fringe-mode' calls `modify-all-frames-parameters' which
sets `default-frame-alist'.  I'm now told that `default-frame-alist' was
CHANGED outside Customize although all I actually did was _customizing_
some option.

 > If the problem is in some detail of the behavior of Custom when it is
 > used on `default-frame-alist', maybe we can fix that detail.
 > For instance, maybe those other commands should do somethingto inform
 > Custom of the changes, so that it looks like `default-frame-alist'
 > was set using Custom.

Suppose I set and save a new value for `fringe-mode'.  Should Emacs
automatically set and save the new value for `default-frame-alist'?