Re: Outline mode

[John J Foerch]

"Davis Herring" <address@hidden> writes:
>
> I'm sorry if I'm asking you to repeat yourself, but I (approximately like
> Stefan) would like to see the UI idea instead of the implementation.  In
> my case, though, I'm asking for a (re)description of the UI problem, not
> any UI solution.  To make sure we understand the reference case, consider
> this case, with the C-e that I'm supporting:
>
> * Header
> ** Subheading, with elided body...
> ** Subheading
> Shown body.
>

No problem.  At "** Subheading, with elided body...\n" the newline
after the ellipsis is the newline character just before the next
subheading.  Users should definitely not be prevented from placing
point at this character, because it is an ordinary visible character,
and people may have any number of reasons for wanting to put point
there (maybe they just want to `describe-text-properties' for some
reason).  Thus, the movement commands are not the problem.

However, it would be preferable, at least to me, to have that newline
be invisible, and the newline immediately after the header to be
visible, so that when I go to the end of that heading line, by
whatever method, point is truly *on* the heading line.  Not having to
arrow to the left saves me both keystrokes and cogitation.  The reason
emacs cannot do this right now, is that if you hid that newline, and
displayed the newline after the header instead, your outline would
look like this:

* Header
** Subheading, with elided body
...**Subheading
Shown body.

In that case, you could put point at the end of your subheading, and
edit with no funny surprises.  Derived modes would also see that you
were in fact on a header-line (this problem is illustrated by
org-cycle in org-mode, which can't cycle if point is to the right of
the ellipsis).  But of course that outline looks silly.  We expect the
ellipsis to appear on the header line.

For outline-mode to work as I would like it to work, the invisible
entry needs to collapse at column 0 of the line after its
corresponding header.  But the ellipsis needs to be displayed one
character before the invisible text, so that it can appear on the same
line as the header.

Currently, the mechanism for displaying the ellipsis can only specify
*whether* to display an ellipsis.  I would like for it to be able to
specify *where* to display the ellipsis.

Now I'll be gone for a few days.  I should be back online to continue
this discussion on Monday.

Thank you,
--John