It's a dubious metric anyway considering that most editors support some form of tab completion. That being said, it's useful for a new practitioner to be able

It's a dubious metric anyway considering that most editors support some form of tab completion. That being said, it's useful for a new practitioner to be able to experience a language's flow or cadence without having to come up with syntactically correct code themselves -- like just getting your feet wet. In fact, I wish they'd put this up on GitHub, I'd like to add modes for Ruby, for koans, and for augmented documentation.