bug#43092: 26.3; mode-line-frame-identification mode-line-buffer-identification " " mode-line-position (vc-mode vc-mode) " " mode-line-modes mode-line-misc-info mode-line-end-spaces

[Drew Adams <drew.adams@oracle.com>]

I may be missing something - please close if so (but hopefully let me
know what I'm missing).

The default value of `mode-line-remote' is this:

(#("%1@" 0 3
   (mouse-face mode-line-highlight
               help-echo
               #f(compiled-function
                   (window _object _point) #<bytecode 0x1093abb>))))

(FWIW, it's too bad that users see that #<bytecode...> thingy, but maybe
there's no good alternative.)

I don't see the %-construct "%@" described anywhere.  Presumably "%1@"
means show what "%@" shows, but padded if needed so the field width is
at least one char.  But what does @ itself do?

A guess is that it does nothing, and its only purpose here is to enable
the mouse-face and help-echo on the single pad char.

If so, than a second guess might be that any "%X" construct, where X is
not one of the chars documented, adds nothing other than perhaps padding
chars and properties such as `help-echo' (and allows for `eval' etc.).
If so, that should be documented, no?

In GNU Emacs 26.3 (build 1, x86_64-w64-mingw32)
 of 2019-08-29
Repository revision: 96dd0196c28bc36779584e47fffcca433c9309cd
Windowing system distributor `Microsoft Corp.', version 10.0.18362
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''