Re: How to highlight columns?

Dan Bar Dov wrote:

> I'd like to highlight all text/code that's beyond column 80.
> I cannot figure how to set font-lock to do that, not how to write an
> interactive functions to do that.

Here's a simple example:

(defun highlight-tail ()
  (interactive)
  (let ((exp "^.\\{1,80\\}\\(.*\\)$")
	(face (find-face 'highlight)))
    (while (re-search-forward exp nil t)
      (let* ((start (match-beginning 1))
	     (end (match-end 1))
	     (extent (make-extent start end)))
	(set-extent-property extent 'face face)
	(goto-char end)))))

It highlights everything after the 80th character, which may not be
the 80th column due to characters spanning multiple columns (primarily
tabs, but also control characters using ^M or \015 display forms).

-- 
Glynn Clements <[email protected]>