Using version 3.0.3
r = RedCloth.new "-- hyphens to the left of me --"
=> "-- hyphens to the left of me --"
r.to_html
=> "<p>—hyphens to the left of me—</p>"
3.0.4 is buggy in other places iirc (haven't used it since _I_ was tripped up) - and afaik it's on the backburner at the moment - stick with 3.0.3, works fine.