Tags right alignment with font-lock

["Nicolas P. Rougier (inria)" <nicolas.rougier@inria.fr>]

Hello,

I'm using font lock to have tags right aligned with the following 
code:

;; Right alignment (char wise)
(add-to-list 'font-lock-extra-managed-props 'display)
(font-lock-add-keywords 'org-mode
  `(("^\\*+.*?\\( \\)\\(:[[:alnum:]_@#%:]+:\\)$"
     (1 `(face nil
               display (space :align-to (- right 3
                                           ,(org-string-width 
                                           (match-string 2)))))
        prepend))) t)

;; Right alignment (pixel wise)
;;(font-lock-add-keywords 'org-mode
;;   `(("^\\*+.*?\\( \\)\\(:[[:alnum:]_@#%:]+:\\)$"
;;      (1 `(face nil
;;                display (space :align-to (- right 3
;;                                            (,(org-string-width 
                                              (match-string 2) 
                                              t)))))
;;         prepend))) t)

I've not tested it thoroughly but it seems to be working 
reasonably well on my machine. It is pretty similar to the code 
posted by Ihor Radchenko (thread on "variable-pitch-mode misaligns 
org-mode heading tags") and I wonder if there are any drawback 
with such techniques (too slow? does not work on all situations?)

Nicolas

-- 
Nicolas P. Rougier —— www.labri.fr/perso/nrougier
Institute of Neurodegenerative Diseases, Bordeaux