In D4274#124268, @karol-bisztyga wrote:

The problem is I couldn't figure out how to modify anything inside of the generator's body:

let mut x = 0;
let outbound = async_stream::stream! {
  //...
  x += 1;
  //...
};
println!("=> {}", x);

The output would still be 0. I tried borrowing, using Arc (can Rc/Arc be mutated at all?), but nothing worked.
This has to be generator-specific stuff, but generators are not well documented afaik.

Something like this works like a charm:

let mut b = false;
{
  b = true;
};
println!("hey {}", b); // true

@varun

That's strange... one possible option might be to try Rc<RefCell<T>>, but there should be an easier way.

I'm going to revert this, we can create a follow-up about this, I couldn't hack it and I have no idea how can I make it work. @varun ?

Didn't have time to investigate the generator thing, and honestly not sure I'll get to it tomorrow either. Can you please create a follow-up task in Linear? You can assign it to me