genawaiter

This crate lets you use generators on stable Rust. Instead of using yield, which won't be stabilized anytime soon, you use async/await, which is stable today:

use genawaiter::rc::{Co, Gen};

async fn odd_numbers_less_than_ten(co: Co<i32>) {
    let mut n = 1;
    while n < 10 {
        co.yield_(n).await;
        n += 2;
    }
}

for n in Gen::new(odd_numbers_less_than_ten) {
    println!("{}", n);
}

Result:

1
3
5
7
9

See the docs for more.