Select?

I'd initially picked this package to test because I saw it used crossbeam channels, and so presumably would be interoperable with the crossbeam ecosystem. However, this doesn't appear to be the case, unless I'm missing some helper functions or st. In particular, `select` is an important primitive in the CSP architecture, but I can't pass the result of `add_rx()` to `select!` because it's not a `Receiver`. Is there another way I haven't seen, to obtain a `Receiver` that I can pass to `select!`?