function __construct()
{
$this->_link_find = sprintf("/<link\\b(?!:)([^>]*)(?!<)>/%s", $this->_re_flags);
$this->_entity_replacements = array('amp' => '&', 'lt' => '<', 'gt' => '>', 'quot' => '"');
$this->_attr_find = sprintf("/%s/%s", $this->_attr_find, $this->_re_flags);
$this->_removed_re = sprintf("/%s/%s", $this->_removed_re, $this->_re_flags);
$this->_ent_replace = sprintf("&(%s);", implode("|", $this->_entity_replacements));
}