The driver of a vehicle emerging from an alley, driveway or building shall stop the vehicle immediately prior to driving onto a sidewalk or onto the sidewalk area extending across any alley way or driveway, and shall yield the right-of-way to any pedestrian as may be necessary to avoid collision, and upon entering the roadway shall yield the right-of-way to all vehicles approaching on the roadway.
(`90 Code, § 20-70)