The common practice is to keep the analogue and digital grounds seperate and then link them at 1 point. Many people that have tried to do this over the years have used various work arounds to do this in a "safe" manner without getting DRC errors. Other people have done things that generated DRC errors and then approved them like create a part that has overlapping pads. In either case, the search gives the impression that the Eagle PCB does not have a standard built in method to allow this. Why?
