I've just looked at the revised lexical syntax and qop is a production of lexeme, but qop is still defined in the context free grammar rather than the lexical syntax. Also, in the context free grammar, the last production for aexp is aexp_{qcon} { fbind1 , ... , fbindn } but I believe should be aexp_<qcon> { fbind1 , ... , fbindn } Thanks Ian, who's going to have to rejig his code some time for the revised report :-(