/**
* Put an item in the collection by key.
*
* @param mixed $key
* @param mixed $value
* @return $this
*/
public function put($key, $value)
{
$this->offsetSet($key, $value);
return $this;
}
/**
* Push an item onto the end of the collection.
*
* @param mixed $value
* @return $this
*/
public function push($value)
{
$this->offsetSet(null, $value);
return $this;
}