I don't comment on this topic because I am not expert enough yet to see its possible consequences.
Regarding D2 development, one of the original design goals of D is to be a not revolutionary language, but to take what's already known as reliable and useful from other languages. Bug lately D has become an experiment: it contains many experimental features that are new, nearly untested in real programs. Their semantics can be sound, but we can't be certain yet, so some of those designs may need to be improved on a semantic level too. And some of them are not even fully implemented. I have used D2 for the last few weeks, and I can say that currently the D2 compiler is so full of bugs, rough edges, or not fully implemented features that in my opinion it's nearly unusable. I have found a new bug every 10 lines or code or so (my code is not normal code, I know). When the book is out people will start looking for a compiler too, so I think it's better to offer them something that works, or they will lose interest quickly, and then it will be harder to call them back to give a second look/chance at/to the language. So my suggestion is to focus on removing bugs, performing small local improvements, to smooth the semantic rough edges, etc. I have listed here less than fifteen small things that I've added to bugzilla, that I think can be improved. They are not real bugs, but they are not large new features, they are usually little local things that smooth corners. Bye, bearophile
