Comment Feed for Channel 9 - Bart De Smet: Rx Update - .NET 4.5, Async, WinRT http://ak.channel9.msdn.com/ch9/fb62/4872116d-8fab-498a-b51a-9f7b011dfb62/BartDeSmetRxNET45WinRT_100_ch9.jpg Channel 9 - Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Bart De Smet has been very busy. As you can imagine, the latest release of Rx (v1.11011.11 (Experimental)) supports the latest (developer preview) .NET version, 4.5. In this release, Bart and company have forged a deeper synergy with the async/await Task-based asynchrony model (see Prefer Async Policy in the Release Notes for this release for more info and watch/listen to this conversation!). In addition, Rx can be used in "Windows 8" Metro style apps. Rx v1.11011.11 (Experimental) features include: Improved Exception Management Prefer Async Policy Interoperability with Task<T> FromEventPattern Support for WinRT Events Various Changes to System.Reactive The New System.Reactive.WindowsRuntime Assembly This release of Rx includes support for WinRT interop and to build Metro style applications leveraging Rx for event processing IAsyncInfo Conversions Release Notes Download en Thu, 23 May 2013 01:45:54 GMT Thu, 23 May 2013 01:45:54 GMT Rev9 Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT posted by Dylan Meeus

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541389219622397 Thu, 13 Oct 2011 21:42:01 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541389219622397 Dylan Meeus Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Still no native Rx ? Devil

posted by felix9

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541698071440650 Fri, 14 Oct 2011 06:16:47 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541698071440650 felix9 Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT
tia

posted by tony

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541705735135082 Fri, 14 Oct 2011 06:29:33 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541705735135082 tony Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT posted by Robert Baarda

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541822856746329 Fri, 14 Oct 2011 09:44:45 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541822856746329 Robert Baarda Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Charles, Rock N' Roll is your thing, don't let anyone tell you otherwise!

/Rock n' Roll!

PS. listening to Bart is awesome!

posted by leidegre

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541863702825084 Fri, 14 Oct 2011 10:52:50 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541863702825084 leidegre Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT
I have a question, though: Since Task<T> is "the" abstraction for single-valued asynchrony, why not make IObservable's folding operators (Aggregate, First, Last, etc.) return a Task<T> instead of a single-valued IObservable<T>?

posted by Jeff

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541874615197777 Fri, 14 Oct 2011 11:11:01 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541874615197777 Jeff Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Because you want to continue using observables,..

If it would return Task<T> you would be stuck.

posted by Maddus Mattus

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541894213561999 Fri, 14 Oct 2011 11:43:41 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541894213561999 Maddus Mattus Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT I think you should move those 'txt.Text = "<Stopped>"' statements out of the using block ...... no ?

Update. oh, maybe even setting text.Text after Dispose() wont elimate the problem.

I guess the scheduler or 'sync context' has a 'message queue' kinda thing, and if a 'txt.Text = Key' is already in the queue, unsubscribing or Dispose wont remove it from the queue, so it could be executed after <Stopped> and overwrite the txt.Text ? right ? Maybe the fact of you are subscribing to KeyDown events could help here since its in UI thread and message queue too, but what if you are observing something really 'async' ? Perplexed

posted by felix9

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541917103465667 Fri, 14 Oct 2011 12:21:50 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541917103465667 felix9 Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @Maddus Mattus: Did you watch the video? Bart talks about how IObservable<T> and Task<T> live nicely together in the new version of Rx.

posted by ninjeff

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541973244569094 Fri, 14 Oct 2011 13:55:24 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634541973244569094 ninjeff Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Could the capabilities of Project Roslyn, assist in "magic" strings problems on events, by provide compile-time checking? or would it require a change to the lexer / parser.

posted by AdamSpeight2008

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542103926554866 Fri, 14 Oct 2011 17:33:12 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542103926554866 AdamSpeight2008 Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT I like "Rock n Roll"  Keep saying it! Smiley

posted by AceHack

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542160585632221 Fri, 14 Oct 2011 19:07:38 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542160585632221 AceHack Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @Jeff: While Task<T> would be a good fit for single-value asynchronous results coming out of the Rx APIs, there are a few things we don't want to get into.

First of all, staying in IObservable<T> allows for further composition, which is very rich in the world of Rx. A typical example I always bring up is to apply the Timeout operator to the resulting sequence. With Task<T> you can do similar things using WhenAny or by using cancellation mechanisms, but it's less sexy.

Secondly, by going to Task<T> there's an implicit change in scheduler affinity. Having the ability to control scheduling through the IScheduler abstraction and having a more free-threaded world is an advantage of Rx we don't want to loose due to implicit changes of primitives.

Having said all of this, users can still go to a Task<T> object explicitly by using the ToTask operator. However, for the simple task (pun intended) of awaiting the result of such a single-valued observable sequence, support is right there in Rx to use "await" directly.

posted by bdesmet

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542190027210603 Fri, 14 Oct 2011 19:56:42 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542190027210603 bdesmet Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @felix9: The test code you saw on the screen is not flawless indeed. In general, it's possible for the sequence to produce an OnNext message before the Dispose call to the subscription occurs. The fix is quite simple though: use the Finally operator in Rx to run code after the sequence completes or gets disposed.

posted by bdesmet

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542191919291595 Fri, 14 Oct 2011 19:59:51 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542191919291595 bdesmet Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @AdamSpeight2008: Remains to be seen. Notice the trend of reducing magic strings in pretty much every recent release of the languages (e.g. LINQ instead of queries in strings, dynamic instead of invocation calls with member names in strings, call info attributes instead of hardcoding the current member's name, etc.).

Personally, to reduce the event conversion friction I'd invest in a conversion of events to IObservable<T> like F# does, but at this point there are no such plans.

posted by bdesmet

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542194755333059 Fri, 14 Oct 2011 20:04:35 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542194755333059 bdesmet Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT cool stuff!

i really wish anders will allow us to treat events like a normal multicast delegate properties, that way you could write extensions methods for things like rx on them Smiley

posted by aL_

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542245096073183 Fri, 14 Oct 2011 21:28:29 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542245096073183 aL_ Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Guys,

Do you plan to release a version of Rx built against the Portable Library Tools?

posted by ligAZ

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542581742207438 Sat, 15 Oct 2011 06:49:34 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542581742207438 ligAZ Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT Some clever work going on there. I really like the new WinRT event model and how it fits hand in glove with Rx. And of course the new exception handling enhancements to Rx looks really great. A lot of goodies in the box.

Rock 'n Roll !

posted by exoteric

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542654538106111 Sat, 15 Oct 2011 08:50:53 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542654538106111 exoteric Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @bdesmet: Thanks for the response, Bart.

Seems like you had to pick between two slightly awkward choices: return a Task<T> and deal with the gaps and differences, or return an IObservable<T> that breaks the abstraction slightly.

In a perfect world, I think Task<T> and IObservable<T> would have the exact same interfaces for the shared concepts that you mentioned. Given that they don't, though, the choice makes sense.

posted by ninjeff

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542764832349062 Sat, 15 Oct 2011 11:54:43 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542764832349062 ninjeff Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @ligAZ: We're actively working with the PLIB folks on making Rx portable. The main thing required is to have IObservable available in all supported platforms. At this point, we can't commit to a time frame, but we're on it Smiley.

posted by bdesmet

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542769955554196 Sat, 15 Oct 2011 12:03:15 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542769955554196 bdesmet Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT @ninjeff: One thing that would help is to have Task implement IObservable. Given that any multi-value concept has the single-value case covered too, that'd be a good way to think about it. However, in the synchronous case, there's no such implicit conversion between a multi-value thing (e.g. an array) that happens to have a single value and its contents (an "unpack" operation). Rest assure we are (and will continue to be) thinking about co-evolution and co-existence...

posted by bdesmet

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542774203029933 Sat, 15 Oct 2011 12:10:20 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634542774203029933 bdesmet Re: Bart De Smet: Rx Update - .NET 4.5, Async, WinRT So this is what you couldn't talk about at Mix, isn't it Bart, otherwise you'd have been revealing WinRT.  Smiley  I was surprised to discover Wes has left the team.  He'll be missed. Sad  I wish him the best at his new venture.  I do wish you and Wes would blog again. 

There must be something coming down the pipe related to Linq-to-Cloud, and NoSQL.  Can you tell us anything about that and how Rx relates?

 

posted by Richard.Hein

]]> http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634544863280525095 Mon, 17 Oct 2011 22:12:08 GMT http://channel9.msdn.com/Shows/Going+Deep/Bart-De-Smet-Rx-Updat-NET-45-Async-WinRT#c634544863280525095 Richard.Hein