final private static function _hasFileKeys(Array $file): Bool
	{
		$valid = true;
		foreach(['error', 'tmp_name', 'type', 'size', 'name'] as $key) {
			if (! array_key_exists($key, $file)) {
				$valid = false;
				break;
			}
		}
		return $valid;
	}
final private static function _hasFileKeys(Array $file): Bool
	{
		$valid = true;
		foreach(['error', 'tmp_name', 'type', 'size', 'name'] as $key) {
			if (! array_key_exists($key, $file)) {
				$valid = false;
				break;
			}
		}
		return $valid;
	}
final private static function _hasFileKeys ( Array $ file ) : Bool { $ valid = true ; foreach ( [ 'error' , 'tmp_name' , 'type' , 'size' , 'name' ] as $ key ) { if ( ! array_key_exists ( $ key , $ file ) ) { $ valid = false ; break ; } } return $ valid ; }
Verifies that an array has all keys expected of a file upload
@param  Array $file Array, such as from `$_FILES` to validate
@return Bool  If $file has all array keys expected of an upload
Verifies that an array has all keys expected of a file upload