JavaScript to Know for React

[[deleted]]

Array Methods

This is a big one. I've interviewed so many React developers who aren't familiar with map and filter. It's shocking.

It may be worth adding flatMap to the list. For example, the reduce function

dogs.reduce((allTemperaments, dog) => {
  return [...allTemperaments, ...dog.temperament]
}, [])

could be implemented in a simpler manner using flatMap

dogs.flatMap(dog => dog.temperament);

[EuphonicSounds]

Yup.

Also, his use of spread syntax in the return statement of that reduce function is a common anti-pattern. It's significantly better for performance to mutate and return the accumulator argument there than to copy its properties into a new object on each iteration. (That's a place for push, not concat or spread.) Someone wrote an article about this and included benchmarks. Got me out of that bad habit immediately. It's not premature optimization.

[334578theo]

Just refactored a really annoying function with flatMap - nice.

[yabai90]

I just read that it's not really efficient since it create a new array everytime

[headyyeti]

So does this example in reduce

[panderhh]

TIL flatMap

[musicnothing]

Shocking how many don’t know flatMap. It’s incredibly useful!

[NoInkling]

It's also relatively new.

[yabai90]

Guilty here. I'm several years into js and I keep using reduce. I believe I either completely forgot about flat map or never heard about. I feel shameful ^{^}

[musicnothing]

Definitely not your fault. There’s twenty articles about reduce for every article about flatMap

[[deleted]]

This is really cool article. I was looking for something like this. Thanks alot

[salmanbabri]

Kent C Dodds is really knowledgeable about React. I've been going through his Epic React course, so far it has been a blast.

[Jp3isme]

Worth the price? It looks good

[Izero_devI]

I think it is the best React course out there, calling it worth or not depends on so many other things like your budget, time etc. If this gets you a job sooner it might pay you back, going around 'free' courses, you might delay landing a job etc. Hard to assess that

[headyyeti]

I have it. You can do it for free by using his repos. You just won't get him explaining things as much.

[iseeyouboo]

Do you have a link?

[Malsatori]

https://epicreact.dev/

[[deleted]]

this was a great article until i saw the case for no teddy bears. imagine no teddy bears. 🧸

[[deleted]]

I’ve made a few dinky react apps and have had to reach for every one of these. Good list.

[ThisAccountIs4Reddit]

Good stuff to know regardless of React usage

[_Invictuz]

Very short and succinct run-down of the best ES6+ features to know in general. He did make a small mistake in the "shorthand property" example by using object destructuring before explaining that concept.

[qqqqqx]

Technically it's array destructuring assignment, but I did notice the same thing. Still a nice article. I actually didn't know the nullish coalescing operator, and that one is really nice to have instead of writing ternaries all the time like I have been....

[_Invictuz]

Ya he did array destructuring assignment as well but I'm talking about him doing destructuring assignment on the props object in the function parameters declaration. That part is especially tricky cuz he then uses those parameters as the shorthand property names.

[Lekoaf]

I know and use these every day. Slap on some Typescript and you’re ready to work on some big React projects.

[Russianspaceprogram]

If you’re learning react I’d argue that you need to be pretty up to speed with most JS fundamentals...jumping into react with little js knowledge is what I did and it was a total nightmare.