private static boolean isNumeric(Memory k) {
        if (k.isNumber()) {
            return true;
        }

        if (k.isString()) {
            try {
                Double.parseDouble(k.toString());
                return true;
            } catch (NumberFormatException e) {
                return false;
            }
        }

        return false;
    }
We should keep trace when traversing arrays.
exts/jphp-zend-ext/src/main/java/org/develnext/jphp/zend/ext/standard/HttpQueryBuilder.java