We've discussed it before, but it's largely seen as overlapping in functionality with topic namespaces. If you have a use case that is made possible with keys, then that would be interesting to hear about it. However, there are quite a few little details for implementing the key field which are not straightforward to me, like: - each vendor has its own way of defining them - dealing with key fields in nested messages - use of them has to be made visible from all of the ROS tools Probably other things I cannot even think of now. So unless there is a big use case which is not possible with namespaced topics, I think we'd probably not expose it. --- [Visit Topic](https://discourse.ros.org/t/keys-in-msg/1942/2) or reply to this email to respond. If you do not want to receive messages from ros-users please use the unsubscribe link below. If you use the one above, you will stop all of ros-users from receiving updates. ______________________________________________________________________________ ros-users mailing list ros-users@lists.ros.org http://lists.ros.org/mailman/listinfo/ros-users Unsubscribe: