bug#3824: 23.1.50; too much effort is put into handling Scheme S-expression comments, causing problems

Gosh, this must have gotten buried in my inbox a long time ago, and I
completely forgot about it...  Sorry about that!

   Date: Tue, 14 Jul 2009 15:52:52 -0400
   From: Stefan Monnier <[email protected]>

   > Emacs should treat `#;' as whitespace, nothing more.

   Of course, that's also incorrect with its own set of problems (mostly
   indentation), but admittedly, those problems are easier for the user to
   understand/predict.

What problems?  I think it would be perfectly reasonable for #; not to
affect indentation except inasmuch as it moves code following it on
the same line by two columns just like two spaces would.  For example,
I think the following is reasonable indentation:

(cond ((foo? bar) baz)
  #;
      ((quux? zot) mumble)  #;
      ((grog? swat) zoogle)
      #;((blort? gronk)
         (frobnozzle))
   #; (else (frotz)))

I wouldn't use the second two examples myself, because it takes zero
effort to make an editor treat #; as the start of a line comment
(e.g., Edwin does this) and that works perfectly well as long as you
don't put anything interesting on the line.

   Can you try the patch below?

I tried it.  Seems to work on a couple simple cases I threw at it, but
I haven't tried it in anger yet.