If Rust ever gets a native generator syntax, this might be become achievable because one would be able to say: `yield transmit` to "write" data whilst staying within the context of your async operation. In other words, every `socket.write` would turn into a `yield transmit`.

To read data, the generator would suspend (.await) and wait to be resumed with incoming data. I am not sure if there is nightly syntax for this but it would have to look something like:

  // Made up `gen` syntax: gen(yield_type, resume_type)
  gen(Transmit, &[u8]) fn stun_binding(server: SocketAddr) -> SocketAddr {
   let req = make_stun_request();

   yield Transmit {
      server,
      payload: req
   };

   let res = .await; // Made up "suspend and resume with argument"-syntax.
   
   let addr = parse_stun_response(res);

   addr
 }