Functional programming looks nice and shiny until you have to manage mutable state. Even more, in many situations the mutations come from multiple threads. At this point you are tempted to drop the immutability flag and use some good old destructive updates. The problem is that now you are losing readability and composability. What can be done? How can you model such a situation?
In this talk I will show how you can use Reactive Extensions (a.k.a. Rx) to build real world concurrent applications from composable entities. We will also look a bit at the Rx implementation, just enough so it doesn't look like magic.
The code shown will be in F# but there are Rx implementations for most modern languages so you can apply these ideas in your project.