anchor.diff:  metaLiteral returns [MetaLiteral meta]
       @init { TypeLiteral tl=null; 
               MemberLiteral ml=null; }
  -    : d1=BACKTICK
  +    : d1=TYPE_LITERAL_DELIMITER
         { tl = new TypeLiteral($d1);
           $meta = tl; }
       (
  
positive.code:         }
          ;
  
  BACKTICK
      : '`'
      ;
  
  
negative.code:     | m3=memberName
        { ml.setIdentifier($m3.identifier); }
      )
        d2=TYPE_LITERAL_DELIMITER
        { $meta.setEndToken($d2); }
      ;
  
  