protected function indexElement(HTML_Element $element)
{
try {
$property = $this->_property;
$pval = $element->{$property};
if ($pval !== null) {
if (array_key_exists($pval, $this->_index)) {
$this->_unique = false;
if ($this->_require_unique) {
throw new HTML_Duplicate_Attribute_Exception($property, $pval);
}
$this->_index[$pval][] = $element;
} else {
$this->_index[$pval] = array($element);
}
}
} catch (HTML_No_Such_Element_Attribute_Exception $e) {
}
if ($element instanceof HTML_Container) {
$sub_elements = $element->getContents();
foreach ($sub_elements as $sub_element) {
$this->indexElement($sub_element);
}
}
}
