a SingletonSample instance was created !<hr/>instance ID : 22e3108300d7c631cc043bb6fa1d5800<br/>$instance1->getId() === $instance2->getId() : ture<hr/><br />
<b>Fatal error</b>:  Uncaught RuntimeException: Clone is not allowed againstSingletonSample in /var/www/vhosts/www.yuulinux.tokyo/httpdocs/demo/Design-Pattern-Primer-by-PHP/Singleton/SingletonSample.class.php:58
Stack trace:
#0 /var/www/vhosts/www.yuulinux.tokyo/httpdocs/demo/Design-Pattern-Primer-by-PHP/Singleton/index.php(27): SingletonSample-&gt;__clone()
#1 {main}
  thrown in <b>/var/www/vhosts/www.yuulinux.tokyo/httpdocs/demo/Design-Pattern-Primer-by-PHP/Singleton/SingletonSample.class.php</b> on line <b>58</b><br />