Microsoft's Reactive Extensions

I attended the CMAP (Central Maryland Association of .NET Professionals) meeting. They had a presentation on Microsoft's "Reactive Extensions", a poorly-named package of classes to handle interrupt-driven programming. I also chatted with a few folks who I see only at the CMAP meetings.

The Reactive Extensions package is an interesting addition to the Microsoft toolset. They built it for .NET and also for Javascript, so there are two versions. Microsoft claims that they have the same capabilities. (If they do, then that says something about Javascript. If they don't then that says something about Microsoft.)

Microsoft makes a big deal about this package solving the programming problems of inter-system non-synchronized communication. And it does solve the problem, although Microsoft seems to have forgotten that this solution was available at least thirty years ago before PC-DOS 1.0. The package is a simple variant on event-driven programming, or even interrupt-driven programming, in which a process is interrupted by a second process. Or you can view the solution as a variant on the Observer pattern (which Microsoft does).

My impression is that it is useful, but a but clumsy in implementation. The classes do the job, but I'm not sure classes are needed. A simple interface may be sufficient. And it seems that Microsoft has packed in some extra features (throttling methods and "if" methods) that seem to belong to a different API.

This and other recent innovations in programming tools (Silverlight, Internet Explorer 9, IronPython, IronRuby, etc.) show that Microsoft feels competitive pressure. This is a good thing; Microsoft will provide better products for the market and everyone will gain.

I think the Reactive Extensions will be a big factor in development. It allows for the extension of an event-driven framework. This kind of extension will allow for a coherent set of changes to events and event processing. It may take some time, but the changes in application design will be significant.

I'm not sure about the name, though. "Reactive Extensions" sounds a bit dorky to me. But if my biggest complaint is with the name, then Microsoft is on the right path.