anchor.diff:  
   LINE_COMMENT
       :   '//' ~[\r\n]* -> skip
  -    ;+    ;
  +	
  +WS: [ \n\t\r]+ -> skip;
positive.code: 
  primary
      :   literal
      |   Identifier
      ;
  
  literal
  
negative.code:     ;
  
  fieldDeclaration
      :   accessType? type variableDeclarators delimiter
      ;
  
  variableDeclarators
  