From: Robert Schaaf Date: 2009-06-10T14:51:03+09:00 Subject: Re: treetop grammar problem Of course! Lookahead non-gobbling. A lesson learned. Thanks mightily, Bob Schaaf On Jun 10, 2009, at 12:40 AM, Clifford Heath wrote: > Robert Schaaf wrote: >> But the empty string passes! > > It's not a general solution, but you can require that *something* > follows, using &. > > rule roman_numeral > &. ( stuff ) > end > > There's no better way to write M{0,3} > > Clifford Heath. >