anchor.diff:  	;
   
   modeSpec
  -	:	MODE id SEMI ruleSpec+
  +	:	MODE id SEMI lexerRule*
   	;
   
   rules
  
positive.code: 	;
  
  lexerAlt
  	:	lexerElements? lexerCommands?
  	;
  
  lexerElements
  
negative.code: 	;
  
  alternative
  	:	elementOptions? element*
  	;
  
  element
  