public void On(MovedEvent @event)
 {
     State.Location = new Location
     {
         Address   = @event.Address,
         DateMoved = @event.DateMoved
     };
 }
        public MovedEvent Move(MoveCommand command)
        {
            var movedEvent = new MovedEvent
            {
                Address   = command.Address,
                DateMoved = command.DateMoved
            };

            On(movedEvent);

            return(movedEvent);
        }