public static function fromString($string, $default = true)
{
$array = array();
foreach (preg_split('/\\s+/', $string, -1, PREG_SPLIT_NO_EMPTY) as $token) {
$fragments = explode("=", $token);
$value = isset($fragments[1]) ? trim($fragments[1], "' ") : $default;
$array[$fragments[0]] = $value === 'null' ? null : $value;
}
return new self($array, $default);
}