I'm looking for an email parser for lua, and came across Sean Conner's work [1] Trying to run it with Lpeg 0.12 you get a failure: bad argument #1 to '?' (grammar has too many rules) It used to work with Lpeg 0.10 [2], what new limits has Lpeg 0.12 brought along? [1] https://github.com/spc476/LPeg-Parsers/blob/master/email.lua [2] https://github.com/spc476/LPeg-Parsers/issues/2#issuecomment-23723020