a member of the c++ committee (herb sutter) is writing an compiler for an alternative c++ syntax [0], to c++, with the intent to restrict some semantics of the language for less UB, surprises, etc. i think less implementation-defined behavior is incredibly important; rvo vs std::move, dynamic function call optimization, i wish i didn't have to search asm to check for...

[0]: https://github.com/hsutter/cppfront