Yeah, the whole blog post reads like "if you worked too much with a hammer, everything starts looking like a nail". In other words, it puts the cart before the

Yeah, the whole blog post reads like "if you worked too much with a hammer, everything starts looking like a nail". In other words, it puts the cart before the horse. Effects is a MUCH more general and powerful technique than coroutines. An effect system can help greatly with implementing a coroutine system (instead of dealing with the unfortunate type-level hack Rust uses), but trying to implement an effect system on top of a coroutine system will give you a very limited emulation in the best case and another incoherent mess in the worst. It would've been really great if Rust had a proper effect system, but it's very hard to introduce it into an existing language similarly to how you can not easily introduce borrow checker to C/C++. The messy "keyword generics" proposals only serve as a good demonstration for this. So we probably have to wait for Rust 2 or a different successor language.