docs: @Pure
  	public double distance(BusStop stop) {
  		if (isValidPrimitive() && stop.isValidPrimitive()) {
  			final GeoLocationPoint p = getGeoPosition();
  			final GeoLocationPoint p2 = stop.getGeoPosition();
  			return Point2D.getDistancePointPoint(p.getX(), p.getY(), p2.getX(), p2.getY());
  		}
  		return Double.NaN;
  	}