This is an antlr g4 file.I am trying to figure out why the system.out.println on the num parse rule never hits.

grammar csce322Homework01Part01;

/*

* Lexer Rules

*/

LBEGINING : ('{') {System.out.println("Begin List");} ;

LENDING : ('}') {System.out.println("Conclude List");} ;

RENDING : ('#') {System.out.println("Conclude Row");} ;

DBEGINING : ('[') {System.out.println("Begin Domino");} ;

DENDING : (']') {System.out.println("Conclude Domino");};

COMMA : (',') ;

NUMBER : [0-9]+ ;

WHITESPACE : ( '\t' | ' ' | ' ' )+ {skip();} ;

TRAINS : '

HANDS : '

SECTIONBEGINING: '<<' ;

SECTIONENDING: '>>' {System.out.println("Conclude Section");};

dominoes: section+ EOF;

section: SECTIONBEGINING (TRAINS|HANDS) list+ SECTIONENDING;

list: LBEGINING domino+ LENDING RENDING;

domino: DBEGINNING num COMMA num DENDING ;

num: (NUMBER)*{System.out.println("Half: " + $NUMBER.text);};