Fatal error: Uncaught TypeError: usort(): Argument #1 ($array) must be of type array, null given in /home/b5jrkec8448d/reviewpe_net_public_html/ace/reverse/simple_test_page.php:12 Stack trace: #0 /home/b5jrkec8448d/reviewpe_net_public_html/ace/reverse/simple_test_page.php(12): usort() #1 {main} thrown in /home/b5jrkec8448d/reviewpe_net_public_html/ace/reverse/simple_test_page.php on line 12