public function valid()
{
if ($this->cache === true) {
// check to see if the current position has already been stored
if (!empty($this->results[$this->position])) {
return isset($this->results[$this->position]);
} elseif ($next_date = parent::next()) {
// if it hasn't been found, check to see if there are more
// dates
$this->results[] = $next_date;
return isset($next_date);
}
} else {
// check to see if there is another result and set that as the
// result
if ($next_date = parent::next()) {
$this->result = $next_date;
return isset($this->result);
}
}
// end the foreach loop when all options are exhausted
return false;
}