310 lines
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310 lines
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<h1 class="menu-title">Futures Explained in 200 Lines of Rust</h1>
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<main>
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<h1><a class="header" href="#futures-explained-in-200-lines-of-rust" id="futures-explained-in-200-lines-of-rust">Futures Explained in 200 Lines of Rust</a></h1>
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<p>This book aims to explain Futures in Rust using an example driven approach,
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exploring why they're designed the way they are, and how they work. We'll also
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take a look at some of the alternatives we have when dealing with concurrency
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in programming.</p>
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<p>Going into the level of detail I do in this book is not needed to use futures
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or async/await in Rust. It's for the curious out there that want to know <em>how</em>
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it all works.</p>
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<h2><a class="header" href="#what-this-book-covers" id="what-this-book-covers">What this book covers</a></h2>
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<p>This book will try to explain everything you might wonder about up until the
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topic of different types of executors and runtimes. We'll just implement a very
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simple runtime in this book introducing some concepts but it's enough to get
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started.</p>
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<p><a href="https://github.com/stjepang">Stjepan Glavina</a> has made an excellent series of
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articles about async runtimes and executors, and if the rumors are right there
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is more to come from him in the near future.</p>
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<p>The way you should go about it is to read this book first, then continue
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reading the <a href="https://stjepang.github.io/">articles from stejpang</a> to learn more
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about runtimes and how they work, especially:</p>
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<ol>
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<li><a href="https://stjepang.github.io/2020/01/25/build-your-own-block-on.html">Build your own block_on()</a></li>
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<li><a href="https://stjepang.github.io/2020/01/31/build-your-own-executor.html">Build your own executor</a></li>
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</ol>
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<p>I've limited myself to a 200 line main example (hence the title) to limit the
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scope and introduce an example that can easily be explored further.</p>
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<p>However, there is a lot to digest and it's not what I would call easy, but we'll
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take everything step by step so get a cup of tea and relax.</p>
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<p>I hope you enjoy the ride.</p>
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<blockquote>
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<p>This book is developed in the open, and contributions are welcome. You'll find
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<a href="https://github.com/cfsamson/books-futures-explained">the repository for the book itself here</a>. The final example which
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you can clone, fork or copy <a href="https://github.com/cfsamson/examples-futures">can be found here</a>. Any suggestions
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or improvements can be filed as a PR or in the issue tracker for the book.</p>
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<p>As always, all kinds of feedback is welcome.</p>
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</blockquote>
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<h2><a class="header" href="#reader-exercises-and-further-reading" id="reader-exercises-and-further-reading">Reader exercises and further reading</a></h2>
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<p>In the last <a href="conclusion.html">chapter</a> I've taken the liberty to suggest some
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small exercises if you want to explore a little further.</p>
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<p>This book is also the fourth book I have written about concurrent programming
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in Rust. If you like it, you might want to check out the others as well:</p>
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<ul>
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<li><a href="https://cfsamson.gitbook.io/green-threads-explained-in-200-lines-of-rust/">Green Threads Explained in 200 lines of rust</a></li>
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<li><a href="https://cfsamson.github.io/book-exploring-async-basics/">The Node Experiment - Exploring Async Basics with Rust</a></li>
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<li><a href="https://cfsamsonbooks.gitbook.io/epoll-kqueue-iocp-explained/">Epoll, Kqueue and IOCP Explained with Rust</a></li>
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</ul>
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<h2><a class="header" href="#credits-and-thanks" id="credits-and-thanks">Credits and thanks</a></h2>
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<p>I'd like to take this chance to thank the people behind <code>mio</code>, <code>tokio</code>,
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<code>async_std</code>, <code>futures</code>, <code>libc</code>, <code>crossbeam</code> which underpins so much of the
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async ecosystem and and rarely gets enough praise in my eyes.</p>
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<p>A special thanks to <a href="https://twitter.com/jonhoo">jonhoo</a> who was kind enough to
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give me some valuable feedback on a very early draft of this book. He has not
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read the finished product, but a big thanks is definitely due.</p>
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