My advice on implementing stuff in C:

Note that the context is convincing diehard "C hackers", not necessarily C++ programmers, to migrate. Although, for the latter case, certainly Java is an example of a language directly intended to replace many of C++'s use cases, and both it and C# have been quite successful overall. C++ obviously has a long road ahead of it, and some exciting changes are on the horizon.

That said, of the languages meant to be "a better C++ for C hackers", several have been mentioned, and I don't claim any of will ever be "superior", in the sense of mindshare, marketshare, etc. Just that convincing those C hackers who have repeatedly objected to C++ (pardon the pun), is perhaps a fruitless battle. Personally, I'd kind of like "ooc" to become popular…

As for the "lessons learned", its no surprise that many of the newer languages deliberately make an effort to ease the burden of implemention, speed of compilation, etc. Waiting for non-buggy implementations of C++'s newer features over the years left quite an impression on people…