alt Hacker News> Traits? Nope. We need some way for code reuse.
Says who? You can totally do code reuse using manually-written dynamic dispatch in "rust without traits". That's how C does it, and it works just fine (in fact, it's often faster than Rust's monomorphic approach that results in a huge amount of code bloat that is often very unfriendly to the icache).
Granted, a lot of safety features depend on traits today (send/sync for instance) but traits is a much more powerful and complex feature than you need for all of this. It seems to me like it's absolutely possible to create a simpler language than Rust that retains its borrow checker and thread safety capabilities.
Now whether that'd be a better language is up to individual taste. I personally much prefer Rust's expressiveness. But not all of it is necessary if your goal is only "get the same memory and thread safety guarantees".
> Says who? You can totally do code reuse using manually-written dynamic dispatch in "rust without traits". That's how C does it, and it works just fine.
Rust can monomorphize functions when you pass in types that adhere to specific traits. This is super-handy, because it avoids a bounce through a pointer.
The C++ equivalent would be a templated function call with concept-enforced constraints, which was only well-supported as of C++20 (!!!) and requires you to move your code into a header or module.
Zig can monomorphize with comptime, but the lack of trait-based constraint mechanism means you either write your own constraints by hand with reflection or rely on duck typing.
C doesn't monomorphize at all, unless you count preprocessor hacks.