Introduction to Reactive Extensions

This is a talk I first gave at Nebraska Code Camp on March 10th, 2012

Transcript

1. demo
2. REACTIVE EXTENSIONS
3. github @xpaulbettsx
4. We can no longer write synchronous software. - Abraham Lincoln
5. let’s talk linq.
6. the core of linq is the sequence.
7. pipelines new[] { 1, 2, 3, 4, 5 } .Select(x => x * 5) .Where(x => x % 2 == 0) .ForEach(Console.WriteLine)
8. a sequence is just some stuff, in a particular order
9. linq lets us describe what to do with data when we get it... ...without actually having the data
10. what i’ve described is a monad.
11. I thought this was an Rx talk!
12. let’s talk events.
13. Events Aren’t Com pos able
14. OnMouseUp + OnMouseDown != OnDoubleClick
15. what is an event? OnKeyUp += (o,e) => DisplayASlide();
16. H
17. e
18. l
19. l
20. o
21. (!)
22. an event is just some stuff, in a particular order
23. Observables OnNext OnCompleted OnError ‘h’, ‘i’ no more stuff exception!
24. IObservable<T> IDisposable Subscribe(IObserver<T> observer); observable.Subscribe( x => WriteLine(x), () => WriteLine(“Done!”), ex => WriteLine(“Aieeeee!”));
25. IObservable is a list too
26. subscribe is your foreach
27. Cold <> Hot
28. Subject<T>
29. demo
30. Rx thinks about time
31. IObservable represents one of two things a stream of items a future result
32. Rx Async Methods are methods that return IObservable<T>
33. IObservable<string> ReturnHelloWorld() { return Observable.Return(“Hello World”); } IObservable<string> ReturnHelloWorld() { return Observable.Start(() => { return “Hello World”; }, Scheduler.TaskPoolScheduler); }
34. demo
35. learn more Rx Workshop Videos amzn.to/programming-rx