final TokenType type = operand.getType();
final TokenSubtype subtype = operand.getSubtype();
if (type == TokenType.OPERAND && subtype == TokenSubtype.RANGE) {
//prepare the original Reference
final Reference orgref = ctx != null ?
(Reference) ctx.getVariableResolver().resolveVariable("zkoss.ss.Ref") : null;
final SheetImpl sheet = orgref != null ?
(SheetImpl) orgref.getSheet() : null;
final Book book = sheet != null ?
sheet.getBook() : (ctx instanceof Book) ? (Book) ctx : null;
final String[] range = parseRange(value);
final String sheetnm1 = range[0];