How does `yield` work under the hood? Does it add a reference to some array, with code to loop over all the references with some small timeout until the reference status changes from "pending" to "completed"?
Internally, when the code hits a yield, it's happening inside the resume method. yield works by saving the current state of the generator in the object (see e.g. resume_from in the post), and returning from resume().
|| {
yield 2;
yield 3;
yield 5;
}
fn resume(self: Pin<&mut Self>) -> GeneratorState<i32, ()> {
match self.next_state {
0 => {
self.next_state = 1;
Yielded(2)
},
1 => {
self.next_state = 2;
Yielded(3)
},
2 => {
self.next_state = 3;
Yielded(5)
},
_ => Complete(())
}
}
[1] https://doc.rust-lang.org/beta/unstable-book/language-featur...