{ // $_GET is not defined in code so Hack doesn't know about it and you can't // use it in strict mode. You can interact with it outside of strict mode, // though. return Map::fromArray($_GET); } function getPOSTParams(): Map { // Same deal with $_POST and other magically defined globals return Map::fromArray($_POST); } // Same deal with $_SERVER function isGET(): bool { return $_SERVER['REQUEST_METHOD'] === 'GET'; }