Suggestion: indicate-empty-line tweak

[Edward Welbourne]

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In GNU Emacs 21.2.1 (i386-debian-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2002-03-22 on raven, modified by Debian
configured using `configure  i386-debian-linux-gnu --prefix=/usr 
--sharedstatedir=/var/lib --libexecdir=/usr/lib --localstatedir=/var/lib 
--infodir=/usr/share/info --mandir=/usr/share/man --with-pop=yes --with-x=yes 
--with-x-toolkit=athena --without-gif'
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: C
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

I'm using the nice new feature indicate-empty-line and it is good.  It
lets me know when there's blank lines cluttering the end of the file,
e.g. caused by someone running past end-of-file by over-use of
down-arrow when M-> was intended and next-line-add-newlines was true.

However, it'd be just that tincy wincy bit better if it let me know
when the buffer doesn't end in a newline - an irritating glitch which
makes some programs behave ... surprisingly.

To illustrate, grab yourself a handy buffer, M-x set-variable
indicate-empty-line t, type a line with no newline at the end of the
buffer.  Now add that newline.  Notice that the buffer's appearance
doesn't change, aside from the position of the cursor.  Move the
cursor back to the end of the last line; type C-d and see no visible
change.  To determine whether a file ends in newline, I still have to
go to the end of the file - it isn't immediately visible.

[A solution I considered was to have the marker show on any line not
immediately preceded by a newline: but that would mislead in the case
of an all-hspace final line with no trailing newline.]

Please could the first marker be red (well, OK, the same colour as
`syntactic-error-highlight-face', or some such) or similarly different
when it *isn't* preceded by a newline ?  Or green when it *is* ...

Just any which way, can this mode include (possibly by setting
indicate-empty-line to something other than nil or t, e.g. the name of
the colour to use) the means to spot missing trailing newlines ?

Recent input:
C-r C-r C-r C-r C-r C-r C-a C-k C-n C-n C-n C-n C-n 
C-n C-y C-/ C-/ C-x o C-x o C-x C-f C-a C-k ~ / . e 
m <tab> <return> C-x k <return> C-x C-f M-p <M-backspace> 
s y <tab> i <backspace> e l <tab> i n <tab> <return> 
M-} M-} M-} C-n C-n M-f C-h v <return> C-n C-n C-x 
k <return> C-x o C-n C-n C-n M-f M-f M-f M-f C-h v 
<return> M-x e m a c s - b u <tab> <M-backspace> <M-backspace> 
r e p o r t - e m <tab> <return>

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