>>771
PHP 7.0だか7.1だかならわかるのでは?
Fatal erroになるし

declare(strict_types=1);
function hoge(array $var) { return true; }
$param = (mt_rand(0,1) === 1) ? 'teststring' : array(1,2,3) ;
hoge($param);

PHP Fatal error: Uncaught TypeError: Argument 1 passed to hoge() must be of the type array, string given, called in hoge.php on line 10 and defined in hoge.php:4