case PLUS:
case NOT:
case CONCAT:
case KW_DELETE: {
LexElement prefixExpOpToken = consumeLookAhead();
PrefixOpType prefixOpType = PrefixOpType.tokenToPrefixOpType(prefixExpOpToken.type);
Expression exp = parseUnaryExpression();
if(exp == null) {
exp = parseMissingExpression(RULE_EXPRESSION);
setToEParseBroken(true);