[PATCH] org.el: make org-paragraph-fill ignore \[...\] regions starting and ending a line

[Federico Beffa <beffa@ieee.org>]

> Attached you find a patch with the proposed modification. I would
> greatly appreciate if you could consider it for inclusion in org-mode
> and provide feedback.

Here a more lispy version of the function
`org-fill-paragraph-construct-regions' used in the patch.I guess it
could be more appealing to people on this list :-)

(defun org-fill-paragraph-construct-regions (lbl dmrl)
  "Construct paragraph regions to be filled.

This function takes an ordered list LBL with the positions of org
`line-break' objects and an ordered list DMRL with the start and
end positions of \\=\\[...\\=\\] LaTeX macros beginning and
ending a line.  It returns a list of the form ((r1-beg r1-end)
... (rN-beg rN-end)) with the start end end positions of the
paragraph regions to be filled."
  (let ((lbl-len (length lbl))) ; compute only once length of lbl
    (or
     ;; elementary case 1: no display math regions and 2 entries in lbl
     (and (not dmrl)
      (eq lbl-len 2)
      (list lbl))
     ;; elementary case 2: 1 remaining line break (end of paragraph) and
     ;; 1 remaining display math region.
     (and (eq (length dmrl) 1)
      (eq lbl-len 1)
      (list (list (nth 1 dmrl) (car lbl))))
     ;; remove line-breaks within display math regions
     (and dmrl (>= (nth 1 lbl) (caar dmrl))
      (<= (nth 1 lbl) (nth 1 (car dmrl)))
      (if (> lbl-len 2)
          (org-fill-paragraph-construct-regions2
           (cons (car lbl) (cddr lbl))
           dmrl)
        ;; a displayed math region finished the paragraph
        (org-fill-paragraph-construct-regions2
         (cons (car lbl) (list (caar dmrl)))
         nil)))
     ;; non elementary cases:
     (if (and dmrl (> (nth 1 lbl) (caar dmrl)))
     (cons (list (car lbl) (caar dmrl))
           (org-fill-paragraph-construct-regions2
        (cons (nth 1 (car dmrl)) (cdr lbl))
        (cdr dmrl)))
       (cons (list (car lbl) (nth 1 lbl))
         (org-fill-paragraph-construct-regions2
          (cdr lbl)
          dmrl))))))

Regards,
Federico