URDF Importer disallows link names with /'s in them

I was trying to import a custom URDF, where some of the links have names with /'s in them (i.e. name=“robot_name/base_link”). However, the importer seems to not allow this. It only recognizes one link, with the name changed from “robot_name/base_link” to “robot_name_base_link”. However, none of the other links with /'s in them are affected.

Is this a bug with the parser or intentional?

EDIT: when I changed all the /'s to _'s, it worked. Fail to load Custom URDF presents a similar problem, but in my case, no error was thrown.

@wchen I will add this to the urdf importer documentation (about not using special characters)
I am curious about the other links not being affected, can you link an example urdf file?