Re: the «inverse» function of join-lines

[Nikolay Kudryavtsev]

Weirdly I have not found unfill-paragraph-or-region anywhere in the org 
mode.

But there are different unfill paragraph\region functions on EmacsWiki.

None of them had the advanced functionality I was looking for, so I 
hacked up a better one for myself:

(defun unfill-region (beg end)
  (interactive "*r")
  (replace-regexp-in-region
   "\\([^\.\\!\\?:]\\)\n\s*\\([^-\\*[:digit:][:upper:]\s]+\\)"
                "\\1 \\2" beg end))

This works just about perfectly, since it checks both sides of the line 
break, before removing it. You know, there's the famous quote by H. L. 
Mencken that "For every complex problem there is an /answer/ that is 
clear, /simple/ and wrong." I guess what's also true is that for every 
complex problem there's a simple and incomprehensible regular expression 
solution. Me starting to like regexps nowadays also probably means that, 
I'll end up in a mental asylum soon enough. ;-)

P.S. I don't really understand why do I have to put \s into the second 
group, but without explicitly doing that it just keeps eating whitespace 
from the first \s. I guess, sometimes the less you know, the longer you 
live.