futures-micro

To futures-lite as futures-lite is to futures: smaller.

Features:

• Fun tools to write everything as async fns.

• Tiny, with a single dependency.

• 100% no_std support, no heap allocation required!

• Complete stable compiler support - Uses no nightly features!

• Bootstrap tools:

  • poll_fn - wrap a function into a future.
  • pin!() - pin a value to the stack.

• Futures interface subversion (poll interface from async fns):

  • waker() to get the current waker.
  • sleep() to wait until you are woken.

• Common stuff:

  • yield_once() - lets some other futures do some work .
  • or() - return the result of the first future to complete.
  • or!() - or(), but varargs.
  • zip() - return the result of both futures when they both complete.
  • zip!() - zip(), but varargs.
  • ready!() - unwraps a ready value or returns pending.

Status

Beta? The API we have here seems pretty reasonable now.

If there's something you're missing, you may be looking for futures-lite.

Missing/Removed APIs

There are many APIs you will not find in this crate. Some are absent to keep the crate small and quick to compile, others used to be here but have since been removed. These are:

• pending() - never completes, now in libcore as core::future::pending()
• ready() - completes on first poll, now in libcore as core::future::ready()
• poll_state - wrap a function and some state into a future.

  /// outdated
  poll_state(INITIAL, |state, ctx| {...}).await
  
  /// replacement (NOTE: `*state` should be replaced by `state`)
  let mut state = INITIAL;
  poll_fn(move |ctx| { ... }).await

Changelog

0.5.0 - 2021-03-13

• Switch to using pin-project-lite for pin projections, removing most of the unsafe code.
• Removed next_poll. It wasn't very useful and our implementation may not have been sound. This may explain why I can't find it in futures-lite.

Copyright and License

Copyright (c) 2020 James Laver, Matthieu le Brazidec, Stjepan Glavina, Erik Zscheile, futures-micro contributors, futures-lite contributors

Licensed under Apache License, Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0), with LLVM Exceptions (https://spdx.org/licenses/LLVM-exception.html).

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.