Question about org-emph-re

[Robert Goldman <rpgoldman@sift.info>]

I have been trying to make the generic exporter do fontification (bold,
italic, underline, etc.) and have fairly successfully managed to do this
by cargo-culting the code in org-latex.

But I've run myself on a rock.  I can't figure out what the various
matches are that you get when you match org-emph-re.  There are at least
5 matches, and some may be empty, etc.  I don't /believe/ these are
documented anywhere (or I didn't find the docs).

Can anyone tell me what (match-string x) will be after a (string-match
org-emph-re string) call?  Or tell me where to look to figure it out?

If so, I think I can get the fontification to work for org-generic-export.

(also, emacs-lisp question --- is there some way to /clear/ all the
registers for MATCH-STRING?  When I have been doing this, I have
occasionally had troubles where match-string outputs from previous calls
to string-match seem to "bleed through.")

thanks!
r