Re: Preview of Weave/Picasso v0.1.0, a message-passing based multithreading runtime.

[Araq]

This is excellent work, but what is the protocol that your `spawn` uses/needs. 
I'm asking because I'm wondering about `=sink` vs `=move` vs `=deepCopy` as the 
fundamental building block for thread communication. Rust has both `send` and 
`sync`, see 
[https://doc.rust-lang.org/nomicon/send-and-sync.html](https://doc.rust-lang.org/nomicon/send-and-sync.html)