Promises Tutorials

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    Use Promises Instead of Callbacks with promisify-node

    One of the reasons we love promises so much is because they allows us to avoid the infamous callback hell that we've all experienced in these early days of Node.js.  When I see an API that doesn't use the promise pattern, I get annoyed.  Luckily I've found promisify-node, a...

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    JavaScript Polling

    Polling with JavaScript is one of those ugly but important functions within advanced front-end user experience and testing practices.  Sometimes there isn't the event you can hook into to signify that a given task is complete, so you need to get your hands dirty and simply poll for...

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    fetch API

    One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for.  We've done well to create elegant APIs around XHR but we know we can do better.  Our effort to...

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    JavaScript Battery API: Promises

    Working at Mozilla has afforded me the time to look at new APIs, one of them being the Battery API.  I wrote about the Battery API a while back, when the API was fresh into browsers.  Since then the Battery API has changed, implementing a promise-based...

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    Getting Concurrent With ES6 Generators

    If you've read and digested part 1, part 2, and part 3 of this blog post series, you're probably feeling pretty confident with ES6 generators at this point. Hopefully you're inspired to really push the envelope and see what you can do with...

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    Going Async With ES6 Generators

    Now that you've seen ES6 generators and are more comfortable with them, it's time to really put them to use for improving our real-world code. The main strength of generators is that they provide a single-threaded, synchronous-looking code style, while allowing you to hide the...

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    asynquence: More Than Just Promises (Part 2)

    asynquence Is Promises As we saw in part 1, asynquence is a wrapper abstraction on top of promises, as sequences. A single-step sequence approximates a promise, though they're not identically compatible. However, that's no big deal, since asynquence can both consume and vend standard promises/thenables...

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    asynquence: The Promises You Don’t Know Yet (Part 1)

    on("before", start) Normally, my blog posts (and training workshops, for that matter!) are intended to teach something, and in the process I highlight projects that I've written to explore and experiment in that area. I find that to be an effective aid to teaching. However, this blog post...

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    Write Better JavaScript with Promises

    You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...

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    Camera and Video Control with HTML5

    Client-side APIs on mobile and desktop devices are quickly providing the same APIs.  Of course our mobile devices got access to some of these APIs first, but those APIs are slowly making their way to the desktop.  One of those APIs is the getUserMedia API...