The rendered version is found at: https://cfsamson.github.io/books-futures-explained/
You can find the main example in the repository examples-futures.
This book aims to explain Futures
in Rust using an example driven approach,
exploring why they're designed the way they are, and how they work. We'll also
take a look at some of the alternatives we have when dealing with concurrency
in programming.
Going into the level of detail I do in this book is not needed to use futures or async/await in Rust. It's for the curious out there that want to know how it all works.
This book will try to explain everything you might wonder about up until the topic of different types of executors and runtimes. We'll just implement a very simple runtime in this book introducing some concepts but it's enough to get started.
Stjepan Glavina has made an excellent series of articles about async runtimes and executors, and if the rumors are right there is more to come from him in the near future.
The way you should go about it is to read this book first, then continue reading the articles from stejpang to learn more about runtimes and how they work, especially:
All kinds of contributions are welcome. Spelling, wording or clarifications are very welcome as well as adding or suggesting changes to the content. I'd appreciate if you contribute through a PR.
Feedback, questions or discussion is welcome in the issue tracker.
2020-04-06: Final draft finished
2020-04-10: Rather substantial rewrite of the Reactor
to better the
readability and make it easier to reason about. In addition I fixed a mistake
in the Poll
method and a possible race condition. See #2 for more details.
2020-04-13: Added a "bonus section" to the Implementing Futures chapter where we avoid using thread::park
and instead show how we
can use a Condvar
and a Mutex
to create a proper Parker
. Updated the Finished Example to reflect these changes. Unfortunately, this led us
a few lines over my initial promis of keeping the example below 200 LOC but the I think the inclusion
is worth it.
This book is MIT licensed.