code: public function setName(string $name): void
      {
          if (!empty($name)) {
              if (!is_numeric($name)) {
                  @session_name($name);
              } else {
                  throw new Exception('The session name can\'t consist only of digits, '
                  .'at least one letter must be presented.');
              }
          } else {
              throw new Exception('Empty session name value was passed.');
          }
      }
docs: The method sets the name of current session.
  @param string $name By default it's PHPSESSID.
  @return void
  @throws Exception It's thrown if passed name consists digits only or is empty.