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What's the plan on those fronts if they won't be in 1.0?
There are already crates that offer some of this, like mio.
The end user doesn't really care. The line between the standard library and the language is usually invisible.
It often is a language concern: no async/await in the compiler or language-assisted yielding/scheduling means difficult or impossible concurrency model.
With Rust's borrow checker, IO (already unsafe C FFI) + callbacks are hard to write in a pleasing and safe way.
There's work on non-blocking IO at https://github.com/carllerche/mio, which is looking like one of the more promising approaches, as well as https://github.com/carllerche/eventual which provides higher-level abstractions over it.
There has been some discussion of adding some language support for something like async/await/yield from other languages, but nothing concrete in the near future on the language front.
So, there's usable third-party libraries for it (at least, if you're on a Unix like platform), language support is in the realm of "it would be nice someday".
My remembering is that it uses a different LLVM version than we use, which is very cutting-edge. So we need them to update before it works well.