How can I fix sentences detection in org-mode?

Question

I wanted to use hl-sentences module and discovered in the process that the sentence detection, and thus move between sentence is buggy inside org-mode.

* Title

some text:

- bullet 1
- bullet 2
- bullet 3

** sub-title

If I do an org-forward-sentence when my cursor is positioned in the second bullet for instance. I'm jumping to the end of sub-title.

Worse if I do a org-backward-sentence when I'm in the middle of bullet 2, the first time I'm going back to the beginning (the b) of bullet 2 (which is ok) but if I do another org-backward-sentence I'm jumping back to the start of some text:.

This feel very wrong as by intuition I would imagine that org-backward-sentence should be a projection.

I would prefer that org-mode treat each bullet as a single sentence. And also that starting a new "heading" means the end of any previous sentence.

So perhaps there are good reason for these behaviour if not I would appreciate a pointer on how to fix that problem. Perhaps even propose a PR to org-mode.

Answer 1

The actual problem is that org-mode uses org-forward-paragraph as replacement for forward-paragraph but forward-paragraph is still used in elisp functions.

For an instance forward-sentence directly uses forward-paragraph and org-forward-sentence directly uses forward-sentence.

A hacky solution is to override forward-paragraph with org-forward-paragraph in an advice of forward-sentence:

(defun forward-sentence-with-org-forward-paragraph (oldfun &rest args)
  (if (derived-mode-p 'org-mode)
      (unwind-protect
          (progn
            (advice-add #'forward-paragraph :override (lambda (&optional _arg) (org-forward-paragraph)) '((name . "org-forward-paragraph")))
            (apply oldfun args))
        (advice-remove #'forward-paragraph "org-forward-paragraph"))
    (apply oldfun args)))

(with-current-buffer "test.org"
  (advice-add #'forward-sentence :around #'forward-sentence-with-org-forward-paragraph))

The general solution would be to avoid forward-sentence in org-forward-sentence and to use org-forward-paragraph in org-forward-sentence. But that is quite a bit of work...

Answer 2

emacs-sentence-navigation.el is dedicated to sentence navigation, and will help in most cases... but not in yours, because it lacks "standard" sentences (capitalized word following a period). If your bullets contained "real" sentences, this package would detect them.