1grammar t044trace; 2options { 3 language = Python; 4} 5 6@init { 7 self._stack = None 8} 9 10a: '<' ((INT '+')=>b|c) '>'; 11b: c ('+' c)*; 12c: INT 13 { 14 if self._stack is None: 15 self._stack = self.getRuleInvocationStack() 16 } 17 ; 18 19INT: ('0'..'9')+; 20WS: (' ' | '\n' | '\t')+ {$channel = HIDDEN;}; 21