I reported - in reasonable detail - a similar case study, in Jan 2014: http://oneofmanyworlds.blogspot.in/2014/01/another-go-at-go-failed.html http://oneofmanyw

I reported - in reasonable detail - a similar case study, in Jan 2014: http://oneofmanyworlds.blogspot.in/2014/01/another-go-at-go-failed.html http://oneofmanyworlds.blogspot.in/2014/01/another-go-at-go-.... It was similar in that the combinations of types quickly led to a ballooning of concrete types that had to be implemented. And, not having those concrete types led to an unacceptably high number of type assertions! Generics would have solved the problem succinctly, while preserving programmer intent.