try {
// extract the inner expression
String expression = expression(Args.extract(raw));
if (passthrough) {
atRule.expression(new GenericAtRuleExpression(NORMAL_FUNCTION + expression + ")"));
} else {
Object evaluated = provider.getValue(expression, new Location(null, line, col, -1));
// cannot be empty
if (AuraTextUtil.isEmptyOrWhitespace(evaluated.toString())) {