anchor.diff:  OCTAL       : '0c' [0-7]+
               ;
   
  -NL          : ('\r'?'\n''\t'*)
  +NL          : ('\r'? '\n' ' '*)
               ;
   
   COMMENT     : '#' ~[\r\n]*   -> skip
  
positive.code:             | 'false'
              ;
  
  ID          : [a-z_A-Z0-9' '~!@$%*&^?.]+
              ;
  
  NUMBER      : REAL
  
negative.code:             | OCTAL
              ;
  
  REAL        : DASH? [0-9]+ ( '.' [0-9]+ )*
              ;
  
  HEX         : '0x' [0-9A-Fa-f]+
  