Re: Outline cycling does not preserve point's position

[Nicolas Goaziou <n.goaziou@gmail.com>]

Hello,

Suvayu Ali <fatkasuvayu+linux@gmail.com> writes:

> On Tue, Sep 10, 2013 at 11:02:35AM +0200, Carsten Dominik wrote:
>> 
>> On 10.9.2013, at 10:50, Suvayu Ali <fatkasuvayu+linux@gmail.com> wrote:
>> 
>> > On Tue, Sep 10, 2013 at 10:16:06AM +0200, Carsten Dominik wrote:
>> >> 
>> >> The question is:  What are people using C-arrow for?
>> >> 
>> >> I think the main application is reasonably fast motion
>> >> and selection in a *linear* way.  Is this correct, or do people
>> >> disagree here with me?
>> > 
>> > I use it for navigating a buffer (not necessarily Org) linearly; i.e. go
>> > back and forth between parts I'm working on or to peruse the contents of
>> > a file.  That said, often I feel the need for a navigation command which
>> > allows me to navigate the semantics of the buffer (which exactly what
>> > Nicolas's elements based navigation does).
>> > 
>> >> The amazing element motion commands Nicolas has implement
>> >> correspond to sexp motion, as he has said himself.
>> >> Maybe C-M-f and C-M-b are the better binding match for these?
>> > 
>> > I think you are right here.  There is a need for both.  For me, I use
>> > linear navigation more commonly; so I would prefer C-<up/down> for
>> > linear navigation and some other bindings (like C-M-f/b, as you suggest)
>> > for the elements based motion.
>> 
>> And by linear, I think we don't mean strictly linear, but on a
>> paragraph/table/item scale, ignoring hierarchy.
>
> Yes.  However I think I differ a bit on items.  For me in a list like
> the following, I would call moving by paragraphs _within_ the list items
> linear; so, "Lorem..." → "Cras..." → "Integer..." → "Aenean..." →
> "Pellentesque...", and so on.

Here's a first draft for the linear forward motion. Disclaimer: I didn't
test it thoroughly.

  (defun org-forward-linear-element ()
    (interactive)
    (when (eobp) (user-error "Cannot move further down"))
    (let* ((origin (point))
           (element (org-element-at-point))
           (type (org-element-type element))
           (contents-begin (org-element-property :contents-begin element))
           (contents-end (org-element-property :contents-end element))
           (end (let ((end (org-element-property :end element)) (parent element))
                  (while (and (setq parent (org-element-property :parent parent))
                              (= (org-element-property :contents-end parent) end))
                    (setq end (org-element-property :end parent)))
                  end)))
      (skip-chars-forward " \r\t\n")
      (or (eobp) (goto-char (max (line-beginning-position) origin)))
      (cond ((or (eobp) (= (point) end)))
            ((not contents-begin) (goto-char end))
            ((< (point) contents-begin)
             (cond ((eq type 'item)
                    (end-of-line)
                    (org-forward-and-down-element))
                   ((eq type 'table-row) (goto-char end))
                   (t (goto-char contents-begin))))
            ((>= (point) contents-end) (goto-char end))
            ((eq type 'paragraph) (goto-char end))
            ((eq type 'plain-list)
             (end-of-line)
             (org-forward-and-down-element))
            ((eq type 'table)
             (forward-line)
             (when (>= (point) contents-end) (goto-char end)))
            ((eq type 'verse-block)
             (or (re-search-forward "^[ \t]*$" contents-end t)
                 (goto-char end)))
            (t (error "This shouldn't happen")))
      (when (org-invisible-p2) (goto-char end))))

WDYT?


Regards,

-- 
Nicolas Goaziou