Error [ 0 ]: Call to a member function send_headers() on null

DOCROOT/public/index.php [ 100 ]

 95 	 * Execute the main request. A source of the URI can be passed, eg: $_SERVER['PATH_INFO'].
 96 	 * If no source is specified, the URI will be automatically detected.
 97 	 */
 98 	echo Request::factory(TRUE, array(), FALSE)
 99 		->execute()
100 		->send_headers(TRUE)
101 		->body();
102 }

Environment