PHP null

 ~ $ php main.php

Gold Medal

Fatal error: Uncaught TypeError: Return value of getAward() must be of the type string, null returned in /home/dotinstall/main.php:7

Stack trace:

#0 /home/dotinstall/main.php(11): getAward(40)

#1 {main}

  thrown in /home/dotinstall/main.php on line 7

~ $ php main.php

Gold Medal

~ $ php main.php

Gold Medal

~ $ 

<?php

declare(strict_types=1);

function getAward(?int $score): ?string

{

  return $score >= 100 ? 'Gold Medal' : null;

}

echo getAward(150) .PHP_EOL;

echo getAward(40) .PHP_EOL;