243 lines
13 KiB
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243 lines
13 KiB
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<ol class="chapter"><li><a href="0_introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li><a href="1_background_information.html"><strong aria-hidden="true">2.</strong> Some background information</a></li><li><a href="2_trait_objects.html"><strong aria-hidden="true">3.</strong> Trait objects and fat pointers</a></li><li><a href="3_generators_pin.html"><strong aria-hidden="true">4.</strong> Generators and Pin</a></li><li><a href="4_pin.html"><strong aria-hidden="true">5.</strong> Pin</a></li><li><a href="5_reactor_executor.html"><strong aria-hidden="true">6.</strong> Reactor/Executor Pattern</a></li><li><a href="6_future_example.html"><strong aria-hidden="true">7.</strong> The main example</a></li><li><a href="7_conclusion.html"><strong aria-hidden="true">8.</strong> Conclusion and exercises</a></li><li><a href="8_concurrent_futures.html"><strong aria-hidden="true">9.</strong> Bonus 1: concurrent futures</a></li></ol>
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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 <code>Futures</code> in Rust using an example driven approach.</p>
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<p>The goal is to get a better understanding of <code>Futures</code> by implementing a toy
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<code>Reactor</code>, a very simple <code>Executor</code> and our own <code>Futures</code>. </p>
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<p>We'll start off a bit differently than most other explanations. Instead of
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deferring some of the details about what's special about futures in Rust we
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try to tackle that head on first. We'll be as brief as possible, but as thorough
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as needed. This way, most question will be answered and explored up front. </p>
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<p>We'll end up with futures that can run an any executor like <code>tokio</code> and <code>async_str</code>.</p>
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<p>In the end I've made some reader exercises you can do if you want to fix some
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of the most glaring omissions and shortcuts we took and create a slightly better
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example yourself.</p>
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<h2><a class="header" href="#what-does-this-book-give-you-that-isnt-covered-elsewhere" id="what-does-this-book-give-you-that-isnt-covered-elsewhere">What does this book give you that isn't covered elsewhere?</a></h2>
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<p>That's a valid question. There are many good resources and examples already. First
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of all, this book will focus on <code>Futures</code> and <code>async/await</code> specifically and
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not in the context of any specific runtime.</p>
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<p>Secondly, I've always found small runnable examples very exiting to learn from.
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Thanks to Mdbook the examples can even be edited and explored further. It's
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all code that you can download, play with and learn from.</p>
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<p>We'll and end up with an understandable example including a <code>Future</code>
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implementation, an <code>Executor</code> and a <code>Reactor</code> in less than 200 lines of code.
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We don't rely on any dependencies or real I/O which means it's very easy to
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explore further and try your own ideas.</p>
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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'll like to take the chance of thanking 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> and many other libraries which so
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much is built upon. Reading and exploring some of this code is nothing less than
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impressive. Even the RFCs that much of the design is built upon is written in a
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way that mortal people can understand, and that requires a lot of work. So thanks!</p>
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