This is a series of interactive exercises for learning the Reactive Extensions for Javascript (RxJS). So why is the title "Functional Programming in Javascript"? Well it turns out that the key to learning RxJS is training yourself to use functional programming to manipulate collections. Functional programming provides developers with the tools to abstract common collection operations into reusable, composable building blocks. You'll be surprised to learn that most of the operations you perform on collections can be accomplished with five simple functions:
mapfiltermergeAllreducezipflatMap
Here's our promise to you: if you learn these 6 functions your code will become shorter, more self-descriptive, and more durable. Also, for reasons that might not be obvious right now, you'll learn that these five functions hold the key to simplifying asynchronous programming. Once you've finished this tutorial you'll also have all the tools you need to easily avoid race conditions, propagate and handle asynchronous errors, and sequence events and Ajax requests. In short, these 6 functions will probably be the most powerful, flexible, and useful functions you'll ever learn.
Below are some additional lessons that you can do to better improve your code starting with functional programming and RxJS knowledge.
You can use JSBin with RxJS and RxJS-DOM preloaded so you can use your imagination to create something to show off to the workshop!
- Imperative array handling
- Functional array handling
- Functional event stream handling
- Observables vs Promises
- DOM Events
- Combining two orthogonal Observables
- AND and OR combinators
- Correlational combinators
- Cold and Hot Observables
- FlatMap: the mother of all operators
If you prefer to learn using unit testing and Koans, try the RxJS Koans. Also, want to add more lessons! Send a pull request!
Challenge yourself to build something amazing during your time here. Using RxJS and your imagination, create an application that truly shows the power of RxJS. Here are some community examples to help you along the way.
AngularJS and RxJS Examples
React and RxJS Examples
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Copyright (c) 2015 Matthew Podwysocki
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