foobar:
So basically you're suggesting to implement Integer and Word library types using compiler intrinsics as a way to migrate to better ML compatible semantics.
I think there were no references to ML in that part of Walter answer.
Regarding performance and overflow checking, the example you give is x86 specific. What about other platforms? For example ARM is very popular nowadays in the mobile world and there are many more smart-phones out there than there are PCs. Is the same issue exists and if not (I suspect not, but really have no idea) should D be geared towards current platforms or future ones?
Currently DMD (and a bit D too) is firmly oriented toward x86, with a moderate orientation toward 64 bit too. Manu has asked for more attention toward ARM, but (as Andrei has said) maybe finishing const/immutable/shared is better now.
Bye, bearophile