/**
* Add an attr
*
* @param KeyValuePair $attr
* @return self
*/
public function addAttr(KeyValuePair $attr)
{
$this->_attrs->add($attr);
return $this;
}
/**
* Add key value pair
*
* @param KeyValuePair $a
* @return self
*/
public function addA(KeyValuePair $a)
{
$this->_a->add($a);
return $this;
}
/**
* Add key value pair
*
* @param KeyValuePair $pair
* @return self
*/
public function addKeyValuePair(KeyValuePair $pair)
{
$this->_pairs->add($pair);
return $this;
}