anchor.diff:      
   caseTypes
       : 'of' caseType ('|' caseType)*
  -    -> ^(ABSTRACTS_LIST caseType+)
  +    -> ^(CASE_LIST caseType+)
       ;
   
   caseType 
  
positive.code:     
  block
      : '{' declarationsAndStatements (directiveStatement | expressions)? '}'
      -> ^(BLOCK declarationsAndStatements? directiveStatement? expressions?)
      ;
  
  declarationsAndStatements
  
negative.code: 
  classBody
      : '{' declarationsAndStatements '}'
      -> ^(CLASS_BODY declarationsAndStatements?) //note: the ? is needed here!
      ;
  
  extendedType
  