RobotLocomotion/drake — pull request #22 by bronadav (2014-02-05 18:03:03+00:00)
Title: Add detail to the addJoint error message when joint already has a parent...

I was debugging my urdf file and got an error message about an incorrect link-joint hierarchy. While the error was correct, it didn't give me information as to which links/joints were wrong, so Andy and I went in and changed the error message.