1
Create a Generic Subscriber in RxJS
1m 25s
2
Extend Subscriber to Override `_next` in RxJS
1m 7s
3
Connect a Source to a Subscriber with RxJS `pipe`
3m 33s
4
Use `lift` to Connect a `source` to a `subscriber` in RxJS
1m 36s
5
Create a Reusable Operator from Scratch in RxJS
2m 5s
6
Create Operators from Existing Operators in RxJS
58s
7
Implement the `map` Operator from Scratch in RxJS
3m 5s
8
Chain RxJS Operators Together with a Custom `pipe` Function using Array.reduce
2m 19s
9
Implement RxJS `mergeMap` through inner Observables to Subscribe and Pass Values Through
5m 18s
10
Implement RxJS `switchMap` by Canceling Inner Subscriptions as Values are Passed Through
2m 7s
11
Implement RxJS `concatMap` by Waiting for Inner Subscriptions to Complete
5m 20s
12
`add` Inner Subscriptions to Outer Subscribers to `unsubscribe` in RxJS
2m 8s

Implement RxJS `concatMap` by Waiting for Inner Subscriptions to Complete

RxJS^6.0.0

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Unlike mergeMap and switchMap, concatMap focuses on when "inner" subscriptions "complete" by using a "buffer". Each time concatMap receives a value, it adds each value to a "buffer", waits for previous "inner" subscription to complete, then invokes next with the next value from the "buffer".

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Build Your Own RxJS Pipeable Operators

J. Matthew

~ 5 years ago

Wow, this complex functionality is surprisingly simple to implement...thanks to a very clever design.

As I noted in my comment on the previous video, once again I wasn't able to declare a non-functional property at root on the class—this time buffer—without Webpack's build process breaking. However, the issue was easily solved by appending this.buffer = []; to the end of the constructor.