Stream::flatten_unordered would be nice

[cramertj]

No description provided.

[cramertj]

Triage: I've seen a number of manual impls of this using stream::select_all and select!-- this is still very much wanted.

[luser]

Would this be equivalent to async-std's Stream::merge?

[cramertj]

No-- this would flatten a stream of streams, rather than just combining two streams.

[luser]

OK that makes sense but conceptually this is "take a stream of streams and flatten them into a stream that produces items from any of those streams as they become available", right? If so that's effectively what I was asking for in this async-std issue.

[cramertj]

Yes, that's what I'm describing.