Re: address@hidden: modeline doesn't divulge buffer will go bye bye]

[Robert J. Chassell]

    What do you think of this idea?

        After using this ~20 years it dawns on me: The modeline of a buffer
        with an associated file and that with no associated file look the
        same.  Bad.

        ...

        The most important thing, the fact that this buffer will go
        bye bye without a trace is not mentioned there!

Interesting point!  I am not sure that this information would be
useful to me personally.  However, it is clear that this information
would be useful in general as a way of teaching people that buffers
and the files are different.  My impression is that many novices fail
to make this distinction.  Their mental model is wrong.

Perhaps we could insert a dot in a space to the left of the
`mode-line-frame-identification' segment of a mode line if the buffer
is visiting a file, and replace that glyph with a blank space if the
buffer is not associated with a file.  

I pick `dot' as the visible glyph since it is small, unobtrusive, and
should not make the mode-line appear too cramped.

Thus, in an X windowing environment, mode lines for an Emacs started with

    emacs -q --no-site-file --eval '(blink-cursor-mode 0)'

would look like this:

       --:--        *scratch           (Lisp Interaction) L1 All

       -J:--.       .emacs             (Emacs-Lisp) L1 Top

       --:--        *mail*             (Mail) L1 All

In a character-only terminal, the mode lines would look like this:

    --1-:-- -F2     *scratch          (Lisp Interaction) L5 All

    --1J:--.-F2     .emacs            (Emacs-Lisp) L1 Top

    --1-:-- -F1     *mail*            (Mail) L1 All


Currently, the default value of the `mode-line-frame-identification' is
`" "' if you are using a window system which can show multiple frames,
or `"-%F "' on an ordinary terminal which shows only one frame at a
time.

Perhaps the `-' in `-%F ' should be removed and replaced with a blank
space if we put a dot or space in a column before.

-- 
    Robert J. Chassell                  address@hidden
    Rattlesnake Enterprises             http://www.rattlesnake.com