Announcing the Keyword Generics Initiative
blog.rust-lang.org
blog.rust-lang.org
Either way I'm excited to be able to generalize over asyncness.
*EDIT*: I now see that they explicitly address this question in the post:
> The short answer is: kind of, but not really. "Effect systems" or "algebraic effect systems" generally have a lot of surface area. A common example of what effects allow you to do is implement your own try/catch mechanism. What we're working on is intentionally limited to built-in keywords only, and wouldn't allow you to implement anything like that at all.
> What we do share with effect systems is that we're integrating modifier keywords more directly into the type system. Modifier keywords like async are often referred to as "effects", so being able to be conditional over them in composable ways effectively gives us an "effect algebra". But that's very different from "generalized effect systems" in other languages.
I’m not saying that one design is better than the other, just that this seems to be a bandaid on top of existing tradeoffs made in Rust’s async design that is only 2 years old.