Re: regexp to collapse multiple blank lines into one

[Kevin Rodgers <ihs_4664@yahoo.com>]

Neon Absentius wrote:
 > Actually that also works.  The reason I used "\1" is that I had
 > already grouped the regexp so it saved me typing.
...
 > I don't understand what you don't understand :) My solutions replaces
 > one or more occurences of a regexp with a single occurence.  Perhaps
 > you are worried abour efficiency?

No, it was just that I read \(...\)+ as \(...+\).

\(...\)+ is suspect to me, since in the general case ... can match
different literal strings in the buffer and it wasn't obvious to me what
\1 should refer to.  I know see that the Emacs manual says

      If a particular `\( ... \)' construct matches more than once
      (which can easily happen if it is followed by `*'), only the last
      match is recorded.

but I guess I was effected by my experience with a proprietary text
processing language (which shall remain nameless) that prohibited such
references.

In any case, replacing \(^ C-q C-j \)+ with \1 is 10 key strokes, which
is actually more typing than if you were to replace ^ C-q C-j + with C-q
C-j (6 keys).

-- 
Kevin Rodgers