grammar t030specialStates; options { language = Python3; } @init { self.cond = True } @members { def recover(self, input, re): # no error recovery yet, just crash! raise re } r : ( {self.cond}? NAME | {not self.cond}? NAME WS+ NAME ) ( WS+ NAME )? EOF ; NAME: ('a'..'z') ('a'..'z' | '0'..'9')+; NUMBER: ('0'..'9')+; WS: ' '+;