Yes, it's been oddly satisfying.
> May it have been better to start from scratch?
Ah, the age old question. I can guarantee, though, the answer is no. It took me maybe a couple weeks to convert the entire front end from C++ to D. Contrast that with the Warp preprocessor I wrote for Facebook, which took many months, and I knew what I was doing. And that is just the preprocessor!
Basically, writing a C++ front end takes 10 man years. I know of no effort that took less time, and this is assuming the best in the business doing the writing.
> Was the "D as a better C" approach inspired by your want to transition DMC to D?
Partially, yes. And certainly doing the transition work has improved betterC. Nothing like proving it works than translating a crotchety old horrifyingly complex piece of code written in 1980's style.
I plan on doing this to all my old projects that are still in use.