[O] More helm awesomeness

[Simon Thum]

Hi all,

I recently updated my helm install so it includes 
helm-org-agenda-headings which is just AWESOME (to me at least). A bit 
like org-goto but across all agenda files at once, with goto, refile, 
linking built in. If you haven't tried it, I definitely recommend to do so.


Yet I'm missing a few things so far, I would like to have different 
datasources differentiated by tags, in particular the ARCHIVE tag, and 
the infamous FILETAGS so I cannot just regex my way through as the 
current approach does.

This requires making more use of org-ode when filling helm's buffers. My 
elisp isn't great but I might be able to get there if the approach is sane.

Any pointers are welcome! If you might help me please read on.

I would like to ask what would be the best approach for better utilising 
org infrastructure so I may have separate helm sources for 
live/archived, private/work, the clocking history, stuff like that.

The helm-org definition looks deceptively simple:

https://github.com/emacs-helm/helm/blob/master/helm-org.el

(defun helm-org-agenda-files-headings ()
(interactive)
(helm :sources (helm-source-org-headings-for-files (org-agenda-files))
:candidate-number-limit 99999
:buffer "*helm org headings*"))


FWICT, in effect helm-org is chewing itself through the buffers:

(defun helm-get-org-candidates-in-file (filename min-depth max-depth
&optional fontify)
(with-current-buffer (find-file-noselect filename)
(and fontify (jit-lock-fontify-now))
(let ((match-fn (if fontify 'match-string 'match-string-no-properties)))
(save-excursion
(goto-char (point-min))
(cl-loop while (re-search-forward org-complex-heading-regexp nil t)
if (let ((num-stars (length (match-string-no-properties 1))))
(and (>= num-stars min-depth) (<= num-stars max-depth)))
collect `(,(funcall match-fn 0) . ,(point-marker)))))))

I don't really get what it does but I have a hunch that org-element or 
other org-mode functions could be used to achieve the same with more 
precision. That's what I would need to do. FWIW I'd be happy to take a 
performance hit.

Thanks in advance,

Simon