anchor.diff:          |  '\'' ( ESC_SEQ | ~('\\' | '\'') )* '\''
   	;
   
  -/////////////////////////////
   fragment
   HEX_DIGIT : ('0'..'9'|'a'..'f'|'A'..'F') ;
   	
  
positive.code: fragment
  EXPONENT : ('e'|'E') ('+'|'-')? ('0'..'9')+ ;
  
  
  fragment
  DIGIT : '0'..'9'
      ;
  
negative.code:     ;
      
  literal_list
  	: LPAREN literal_element (COMMA literal_element)* RPAREN
  	;
  	
  literal_element
  