Method set

/**
 * Set data into the session store
 *
 * @param   string  $name   Name of a variable.
 * @param   mixed   $value  Value of a variable.
 *
 * @return  mixed  Old value of a variable.
 *
 * @since   4.0.0
 */
public function set(string $name, $value = null)
{
    if (!$this->isStarted()) {
        $this->start();
    }
    $old = $this->data->get($name);
    $this->data->set($name, $value);
    return $old;
}