Re: default-indicate-buffer-boundaries

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Richard Stallman wrote:

       When I tried out `left' and various other settings for
       indicate-buffer-boundaries, I found it messy and confusing, because it
       more or less at random can either hide other marks in the fringe or be
       hidden by them.

   Can you provide a test case?

Do `emacs -q' and set indicate-buffer-boundaries to 'left.
Hold your finger on the `1' key until you get a continuation line.
Note that the indicate-buffer-boundaries glyph overrides the
continuation glyph that would normally appear in the left margin.
The right continuation glyph is still visible.  But do `M-0 C-l'
and it is out of view, leaving no indication that this is a
continuation line.  But "fixing" this so that the continuation glyph
overrides the indicate-buffer-boundaries glyph would probably be worse. 

Now do `M-x toggle-truncate-lines' (with point still at the end of the
long line).  Now all indicate-buffer-boundaries glyphs are overridden
by the truncation arrows.  But "fixing" this so that the
indicate-buffer-boundaries glyphs override the truncation arrows would
be worse.

I believe to remember that some other Emacs features put glyphs in the
fringe, although I do not immediately remember the details.  Similar
problems occur for them: obviously, they either have to override the
indicate-buffer-boundaries glyphs, or be overridden by them.

It is a while ago that I played around with indicate-buffer-boundaries,
so I do not remember the exact details, but I remember that the
problems were, in my usage, bad enough that I had to decide to reset
it to nil and use `indicate-empty-lines' instead.

`indicate-empty-lines' works well with continuation lines, truncated
lines and other Emacs features that use the fringe.  It only puts
glyphs in the fringe of empty lines, so it does not compete with
anything else.

Sincerely,

Luc.