[emacs] automatically indent to comment-column

the following emacs lisp code makes typing # DWIM. At the "end" of a perl code line it will automatically indent to the comment-column.

Example typing ..."huhu";#the hash... will produce this indentation:

sub load {
  print "huhu";                 # the hash automatically "jumped"
[download]

The code is work in progress if you find bugs feel free to reply here.

(defun my-indent-for-comment (arg)
  "dwim indent-for-comment V0.03"
  (interactive "p")
  (cperl-update-syntaxification (point) (point))
  (if (and
       (not (memq (preceding-char)  '(?$) ))
       ;; (memq (preceding-char)  '( ?\; ?{ ?\( ?\[ ) )
       (memq  (get-text-property (point) 'face) '(cperl-my-trailing-sp
+aces-face nil))
       (looking-at "[[:space:]]*$")
       )
      (cperl-indent-for-comment)
    (insert "#"))
  )        


(add-hook
 'cperl-mode-hook
 (lambda ()
   (local-set-key (kbd "C-#") 'comment-dwim)
   (local-set-key (kbd "#") 'my-indent-for-comment)
   (set-variable 'cperl-comment-column 45 )
   ))
[download]

Plz note I also bound C-# to what normally M-; does, because it's much easier to reach on QWERTZ keyboards and IMHO more intuitive in Perl context. Additionally this command will also automatically comment/uncomment selected text.

UPDATE: You have the choice between different levels of aggressiveness, ATM the command checksš if the hash doesn't follow a blacklist of chars (actually $). You can change this behaviour to more restrictive whitelisting by uncommenting the following line (i.e. has to follow ; { ( [)

Cheers Rolf

š) Additionally to excluding any syntax groups (string,command,...) and assuring that only whitespaces follow till the end of line.

Comment on [emacs] automatically indent to comment-column Select or Download Code

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Re: [emacs] automatically indent to comment-column by LanX (Saint) on May 10, 2010 at 12:43 UTC
The following code will also fix the case of # as delimiter for s///. Example: typing `s#a#b##comment` leads to `s#a#b# # comment` [download] V0.04 `(defun my-indent-for-comment (arg) "DWIM indent-for-comment v0.04" (interactive "p") (cperl-update-syntaxification (point) (point)) (if (and (not (memq (preceding-char) '(?$) )) ;; (memq (preceding-char) '( ?\; ?{ ?\( ?\[ ) ) (memq (get-text-property (point) 'face) '(cperl-my-trailing-spaces-face nil)) (not (get-text-property (point) 'syntax-type)) (looking-at "[[:space:]]*$") ) (cperl-indent-for-comment) (insert "#")) )` [download] checking the "face" may be redundant now... Cheers Rolf	[reply] [d/l] [select]
Re: [emacs] automatically indent to comment-column by LanX (Saint) on May 12, 2010 at 10:23 UTC
The following code will let "backspace" correct an unwanted jump to comment-column, deleting all previously inserted whitespaces. example of phases before and after typing `bla();#<backspace>` (cursor position marked by Ť) `... bla();Ť bla(); # Ť bla();Ť` [download] elisp: (defun my-cperl-electric-backspace (arg) "(Wrapper for my electric commands) Remove inserted whitespaces or call `cperl-electric-backspace'" (interactive "p") (if (not (eq last-command 'my-indent-for-comment )) (cperl-electric-backspace arg) (setq p (point)) (skip-chars-backward "# \t") (delete-region (point) p) ) ) (add-hook 'cperl-mode-hook (lambda () (local-set-key (kbd "C-#") 'comment-dwim) (local-set-key (kbd "#") 'my-indent-for-comment) (local-set-key (kbd "DEL") 'my-cperl-electric-backspace) (set-variable 'cperl-comment-column 60 ) )) [download] Cheers Rolf	[reply] [d/l] [select]