empty lines not highlighted

qwiglydee commented 10 years ago

In GNU Emacs 24.3.1 (x86_64-pc-linux-gnu, GTK+ Version 3.8.2) (ubuntu built) The following code misses highlights in lines before "def"s:

class Foo(object):

    def __init__(self):
        pass

    def __unicode__(self):
        pass

The lines are just empty On screenshot in README.org I see such lines highlighted.

Where is the problem?

antonj commented 9 years ago

The problem is that it is hard to highlight lines without content. It could probably be done by using the overlays and the http://www.gnu.org/software/emacs/manual/html_node/elisp/Display-Property.html but I'm not really sure how :)

The screenshot is probably showing a buffer with spaces on empty lines...

jtamagnan commented 8 years ago

I created this little hack, it adds whitespace equal to the whitespace of the previous section for all blank lines after every save.

(defun add-whitespace (&optional start end)
  (interactive (progn
                 (barf-if-buffer-read-only)
                 (if (use-region-p)
                     (list (region-beginning) (region-end))
                   (list nil nil))))
  (save-match-data
    (save-excursion
      (let ((end-marker (copy-marker (or end (point-max))))
            (start (or start (point-min))))
        (goto-char start)
        (while (and (re-search-forward "^$" end-marker t) (not (>= (point) end-marker)))
      (forward-line -1)
      (let ((line-start (point))
        (line-end   (progn (back-to-indentation) (point))))
        (forward-line 1)
        (insert
         (make-string
          (- line-end line-start)
          32)))
      (forward-line 1)))))
  nil)
(add-hook 'before-save-hook 'delete-trailing-whitespace)
(add-hook 'after-save-hook 'add-whitespace)

Also I feel like this issue should be kept open because it is still an issue that is affecting people

antonj / Highlight-Indentation-for-Emacs

empty lines not highlighted #18