Re: awesome feature (yet to be added?)

[Stefan Monnier <monnier@iro.umontreal.ca>]

> Emacs. My use case is outorg.el that converts programming language buffers
> (structured the outshine way, i.e. with outcommented Org-mode headers)
> temporarily to org-mode for text editing and then back to the
> programming major-mode.

After uncommenting, how do you know which lines should be recommented?
Do you remember them in some variable?  Or do you wrap the code parts in
those (ugly) +begin...+end "brackets"?
Do you uncomment all comments, or only those that "look like Org stuff"?

> the original major-mode. I do this linewise, and in fact outorg can't
> handle those special multiline comments like in C or Java. 

Why do it line-wise?

> A robust generic (= major-mode agnostic) `invert-comment' function as
> part of Emacs that knows how to handle multiline comments too would come
> very handy.

It looks like the exact meaning of such a function is slightly different
for every one, so such a function would need lots of hooks and config
vars to cover all cases.

But you can write your own function starting with

   (defun my-uncomment-region (beg end)
     (let (spt)
       (while (and (< (point) end)
                   (setq spt (comment-search-forward end t)))
         (let ((ept (progn
		      (goto-char spt)
		      (unless (or (comment-forward)
			          ;; Allow non-terminated comments.
			          (eobp))
		        (error "Can't find the comment end"))
		      (point))))
           (uncomment-region spt ept)))))


-- Stefan