Reactive Extensions For JavaScript

Erik Meijer (Microsoft)
Location: Portland 255
Average rating: ***..
(3.86, 14 ratings)

The “A” in “AJAX” stands for asynchronous, and indeed modern Web-based and Cloud-based applications are fundamentally asynchronous. However, asynchronous programming is by no means restricted to mobile, Web, and Cloud scenarios, however. Traditional desktop applications also have to maintain responsiveness in the face of long latency IO operations and other expensive background tasks, and server-side endpoints need to handle thousands of asynchronous requests.

Another common attribute of interactive applications, whether Web/Cloud or client-based, is that they are event-driven. The user interacts with the application via a GUI that receives event streams asynchronously from the mouse, keyboard, and other inputs.

Rx is a LINQ-based library for composing asynchronous and event-based programs that exposes asynchronous and event-based computations as push-based, observable collections via the IObservable and IObserver interfaces that are the mathematical dual of the familiar IEnumerable and IEnumerator interfaces for pull-based, iterable collections.

In this talk we will unveal Rx for JavaScript, a pure JavaScript version of the original Reactive Extensions for .NET that was shipped last fall.

Photo of Erik Meijer

Erik Meijer


Erik Meijer is an accomplished programming-language designer who has worked on a wide range of languages, including Haskell, Mondrian, X#, Cω, C#, and Visual Basic. He runs the Cloud Languages Team in the Business Platform Division at Microsoft, where his primary focus has been to remove the impedance mismatch between databases and programming languages in the context of the Cloud. One of the fruits of these efforts is LINQ, which not only adds a native querying syntax to .NET languages, such as C# and Visual Basic, but also allows developers to query data sources other than tables, such as objects or XML. Most recently, Erik has been working on “Democratizing the Cloud” and preaching the virtues of fundamentalist functional programming in the new age of concurrency and many-core. Some people might recognize him from his brief stint as the “Head in the Box” on Microsoft VBTV. These days, you can regularly watch Erik’s interviews on the “Expert-to-Expert” and “Going Deep” series on Channel 9.

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