/**
* Attempts to return a concrete IDNA instance for either php4 or php5,
* only creating a new instance if no IDNA instance with the same
* parameters currently exists.
*
* @param array $params Set of paramaters
*
* @return object idna_convert
* @access public
*/
public function singleton($params = array())
{
static $instances;
if (!isset($instances)) {
$instances = array();
}
$signature = serialize($params);
if (!isset($instances[$signature])) {
$instances[$signature] = Idna::getInstance($params);
}
return $instances[$signature];
}
