service response empty
The wiki doesn't make it clear if response or request of a ROS service can be empty, and what will happen when either is empty.
I have seen rospy.Service
fails if the handler returns None, so I guess ROS services without any response are not supported. Otherwise, what should the handler return?
But I am still not clear if ROS services with empty requests are officially supported. I see services with empty request can be called with no problem, but it would be nice to see this documented, so that when we see some tools cannot work with this case, we know it is a bug and will try fix it.
Best regards, Yong