What parts of Rust would you like changed, though?
I think the current version, with its minor warts, is a very pleasant and consistent experience for the most part -- very much unlike C++. So I'm not sure what I'd change to such a drastic degree that it'd require such breaking changes.
I would definitely want to see async totally overhauled. Also it would be great if major components of the standard library were all version 1.
And if I want to risk going too far, I'd also advocate for refactoring the type system to be slightly less generic in favor of chasing faster compile times.
Also, ideally the lead designer of SafeLang2.0 would be much more heavy on engineering experience than PL theory. Rust made a lot of tradeoffs that were beautiful in PL theory but are annoying to use on a day to day basis.
I honestly think rust is equal parts amazing ideas and mediocre ideas, and I think a slighky less ambitious language would still be almost as safe (world class compared to any other language) but 10x more fun to use.
Besides the Move and Leak traits mentioned in this article, there are several changes I would make to the standard library if backwards compatibility wasn't a concern, including:
Changing Iterator to make use of Generic Associated Types.
Change std::env::set_var to be unsafe. Because using it in multithreaded program causes undefined behavior for any c code that reads the environment (which includes quite a few libc and posix functions).
Change channels to have a better API that is mpmc and closer to crossbeam.
And probably others I can't think of at the moment.
I'm curious about the "change channels to be mpmc" one. Why isn't it backwards-compatible?
About `std::env::set_var()`, there was a proposal for a `#[deprecated_safe]` attribute that triggers a warning if the function is used without an unsafe block, and eventually make that a hard error in future edition.
I think the current version, with its minor warts, is a very pleasant and consistent experience for the most part -- very much unlike C++. So I'm not sure what I'd change to such a drastic degree that it'd require such breaking changes.