How about something like http://www.inf.puc-rio.br/~roberto/lpeg/ http://www.inf.puc-rio.br/~roberto/lpeg/ ? Since the optional pattern syntax doesn't use back

How about something like http://www.inf.puc-rio.br/~roberto/lpeg/ http://www.inf.puc-rio.br/~roberto/lpeg/ ? Since the optional pattern syntax doesn't use backslashes, they aren't a problem. I'd hack this up myself if Swift weren't Apple-only.