Kim Hamilton and Wes Dyer: Inside .NET Rx and IObservable/IObserver in the BCL (VS 2010)

Posted By: Charles | Aug 4th, 2009 @ 10:02 AM | 53,475 Views | 28 Comments
You recently learned about Erik Meijer's latest innovation, Rx, here on Channel 9. Clearly, judging by the views and comments on that post, it piqued your interest and curiosity. Wes Dyer, a rock star developer on Erik's team of rock stars, implemented a great deal of Rx and helped to design it along with Erik.

Visual Studio 2010 will ship with with two new types, IObserver and IObservable. Rock star developer Kim Hamiliton (you've met her on C9) implemented these two types in the BCL and worked closely with Erik and Wes to insure that Rx in the BCL is designed and implemented to meet the strict requirements for new types in .NET's robust general purpose library. As you've learned previously, IObservable is the mathematical dual of IEnumerable. We of course talk about this here, but from the developer perspective. You've already learned about the math and continuation monad behind this with Erik and Brian Beckman.

Here, Kim and Wes dig into the implementation of IObservable and IObserver in the 2010 version of the BCL. How did Erik and team work with the BCL folks? What were the design decisions that led to the final implementation of the two Rx types in the BCL? What do these two new types enable for .NET developers? This is a great example of how innovation comes to market: incubation teams come up with a brilliant idea, refine it by working with multiple teams and some researchers in MSR, pass it along to a product group, they go back and forth on implementation details and design requirements and finally the new stuff is added to the shipping code base. Great stuff!!

Make sure to watch this all the way through. You never know what kind of magic can happen if you know how to summon a wizard.

Enjoy!
Rating:
4
0
#Aug 4th, 2009 @ 11:15 AM
vesuvius
vesuvius
La Petite Danseuse de Quatorze Ans

So I take it this is not in VS 2010 beta 1, but may be in beta 2? Downloading...

#Aug 4th, 2009 @ 11:22 AM
Charles
Charles
Welcome Change

It will be in VS 2010 Smiley Not sure of the exact ship stage (Beta 2, etc). It will certainly be in RTM...

C

#Aug 4th, 2009 @ 11:29 AM
dot_tom
dot_tom

A.W.E.S.O.M.E. Smiley I don't suppose there's any rough estimate of Beta 2's arrival Charles? Is breath holding advised?

#Aug 4th, 2009 @ 11:40 AM
Charles
Charles
Welcome Change

I'm excited too. This is awesome stuff and very deep in implications for distributed reactive programming on the .NET stack. To be clear, I do not know the exact ship vehicle (meaning, I do not know if beta 2 is the target). All I know is that these two new types will ship as part of VS 2010. The VS People own the timing plan. Me, I'm just a lawnmower. You can tell me by the way I walk.

 

C

#Aug 4th, 2009 @ 12:08 PM
Charles
Charles
Welcome Change

We are actually thinking about this Smiley

C

#Aug 4th, 2009 @ 12:37 PM
gdesroches
gdesroches

In your first C# sample...


var o = Observable.Return(1);



o.Subscribe(
    x  => Console.WriteLine("OnNext({0})", x),
    ex => Console.WriteLine("Error()"),
    () => Console.WriteLine("Completed()")
    );


I see you are creating an IObservable object, and you are subscribing to it, but what is telling the observable object to begin calling the OnNext method on its subscribers?

#Aug 4th, 2009 @ 1:08 PM
Bass
Bass
A computer once beat me at chess, but it was no match for me at kick boxing.

When you say 2010 BCL, you mean .NET 4 right?

#Aug 4th, 2009 @ 1:32 PM
Charles
Charles
Welcome Change

Yes. .NET 4 is the product marketing terminology. Sorry for the confusion.

C

Microsoft Communities