genawaiter

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This crate implements stackless generators (aka coroutines) in stable Rust. Instead of using yield, which [won't be stabilized anytime soon][yield-unstable], you use async/await, which is stable today.

[yield-unstable]: https://doc.rust-lang.org/nightly/unstable-book/language-features/generators.html

Features:

• supports resume arguments and completion values
• supports async generators (e.g., Streams)
• allocation-free
• no runtime dependencies

• built on top of standard language constructs, which means there are no platform-specific shenanigans

let oddnumberslessthanten = gen!({
    let mut n = 1;
    while n < 10 {
        yield_!(n); // Suspend a function at any point with a value.
        n += 2;
    }
});
// Generators can be used as ordinary iterators. for num in oddnumberslessthanten {     println!("{}", num); }

Result:

1
3
5
7
9

And here is the same generator, this time without macros. This is how you do things with default-features = false (which eliminates the proc macro dependencies).

let oddnumberslessthanten = Gen::new(|co| async move {
    let mut n = 1;
    while n < 10 {
        co.yield_(n).await;
        n += 2;
    }
});

See the docs for more.

Development

Install prerequisites

• [Rust]
• [pre-commit]

Install the pre-commit hook

pre-commit install

This installs a Git hook that runs a quick sanity check before every commit.

Run the app

cargo run

Run the tests

cargo test