RE: Modernize frame-title-format: "%b - GNU Emacs"

[Drew Adams]

>>> I don't even think it would be acceptable to go with a default
>>> setting if it were easy to customize this, and it's not (M-x customize
>>> RET frame title RET doesn't work).
> 
> Well, fixing that is a one-liner:
>     Eli> Though not via Customize, you _can_ customize the title: see the
>     Eli> variable frame-title-format.
> (is there a better custom type than 'sexp here?)

I at first had the same reflex.  But I think it's
probably misguided.  The format in question, which
is that of `mode-line-format', is pretty complex
for Customize.

Certainly, it should _not_ just be :type `sexp'.
If Customize is to be helpful then the :type
should be as specific/accurate as possible,
while still covering all possibilities.

I don't think Customize is the immediate answer
here, at least not by just applying it to vars
such as `mode-line-format' and `frame-title-format'.

Instead, we should come up with some simpler ways
to customize such formats - not just toss these
complex variables over to Customize as is.  (That
would be a mistake, I think.)

I, like others, have provided mode-line features.
(See `modeline-posn.el', `modeline-char.el', and
`modeline-win.el' - on Emacs Wiki.)

But I can't imagine any of what those libraries
offer as being things that most users could do
easily (e.g., via Customize).  And I imagine
that the same thing holds for what others have
done with the mode-line.

I think the ease-of-use needs to be brainstormed.

We should probably come up with a "simple" layer
on top of `mode-line-format'.  Something that at
least lets you do some common, simple things.
Something beyond just the existing mode-line
variables.

I have nothing particular in mind - just the
question and the feeling that something could
be done.  `mode-line-format' is a bear.  It's
great, but not simple.

Just a thought.