Reactive Programming from Scratch (JavaScript) - Ep1

Let's build a reactive JavaScript library, inspired by RxJS, from scratch.

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[emmaccode]

Quality editing, good descriptions -- although a bit broad -- was able to follow along perfectly as a julia, assembly, c, c++ programmer. Wanted to make a little reactive library to hook into Julia, maybe even further, via JSExpressions. The use of map() was weird, but I mostly wanted to see how you craft this sort of paradigm in JavaScript. Being a functional programming proponent, this is much like using parametric polymorphism for indexes of the type mutation. Thanks yo!

[Jtoled]

Sidenote: in your example, you used map inside of the emit method in order to perform a simple iteration of the elements in the array. IMO thats a wrong use of the map function, as map primary use case is to apply a transformation fn to every element in the array and collect the results into a new one. So you are generating some overhead.

TL;DR; map != foreach/for

[dancelmarkyosef]

Damn you nailed the idea of doing this series. Thank you very much

[namangarg]

Dude...
You are just crazy !!

Super awesome stuff !! Amazing energy.

I am amazed to find your channel.

Please keep up the great work !!

[sampaiomarcelo]

Great Video. I just love the way you describe things in Computer Science.

[ghostinplainsight]

For your example of tap, you don't need to use curly braces with the return keyword, you can use parenthesis and a comma to do the same thing.
const tap = f => x => (f(x), x)

[JubairAhmadSiam]

Awesome! Looking forward to this series.

[hugodelnegro]

This is my favorite approach to new libraries, I saw a similar one for react hooks, in the end state management ends up looking like a oop thing.
Why did you use a class and not a closure?
I love your channel. It would be super cool if you would also talk about architecture for data oriented architecture, or ecs architecture, or functional programming architecture.
You could also "rebuild" other libraries.

[blokche_dev]

Valuable content as usual! Thanks a lot Christopher.

[aris]

Dude, I love your vids! Right to the point! Thanks

[o.voytyn]

Your observable is subject actually. Subject can emit values to multiple observables by a next method.

[displayblock]

thank you very much from egypt
i am a beginner and i have a suggestion
first is the reactive functional programming is a paradigm?
i think that this will be great if we discuss in this tutorial more than one paradigm
i mean that if we can say if we do this thing by reactive so we will do it that way and if we do the same thing by another paradigm we will do it that way. and this paradigm is better that that paradigm because 1... 2... 3...
it's just a suggestion
and again thank you very much

[rsdntevl]

always top notch material, good stuff

[caliwolf]

this is excellent, thanks for making this!!

[gauravjoshi]

Hi, I am not able to understand function chaining in a pipe can you suggest some reading.Thanks

[Luxcium]

How can I get to that level of vim fluency I only know :wq and jhkl

[attilatoth]

I guess your variadic pipe function is slightly wrong.

In the original version it was const pipe = f => g => g(f(x)) which has a nice property that it can be partially applied.

For example:
const doubleFirst = pipe(double)
doubleFirst(console.log)(1) // => logs 2 to console

So it still needs a second function before the number argument.

But in the variadic form pipe(double) is just double. I cannot write doubleFirst(console.log)(1), I lost the pipeing.

[zeocamo]

map is not a forEach, and you should copy the x for each of the cbs because if any of the cbs is changing the x then it will be changed for the rest of the cbs

[rafaelcisnerosgomez]

ReactiveX So fuckin awesome :D Thanks Chris!

[guillaumeturgeon]

Does anyone know of a "thrush" equivalent in lodash or lodash/fp?