anchor.diff:  ;
   
   specialRegister :
  -	ADDRESS OF dataName
  +	ADDRESS OF identifier
   	| DATE | DAY | DAY_OF_WEEK | DEBUG_ITEM
   	| LENGTH OF identifier | LINAGE_COUNTER | LINE_COUNTER
   	| PAGE_COUNTER
  
positive.code: 	cobolWord | NONNUMERICLITERAL
  ;
  
  qualifiedDataName :
  	(dataName | conditionName)
  	(
  		((IN | OF) (dataName | tableCall))+
  		| (IN | OF) fileName
  	)?
  	| specialRegister
  ;
  
  recordName :
  	qualifiedDataName
  ;
  
negative.code: 	cobolWord
  ;
  
  textName :
  	cobolWord
  ;
  
  // literal ----------------------------------
  