3 Questions: You Don't Know JavaScript | Prime Reacts

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[elirane]

Every time I start to think I know javascript, I watch videos like this and realize how wrong I am

[Eeezus]

lol the chat ate him alive for getting the first question wrong, meanwhile 80% of JS devs would also get it wrong.... the "senior netflix engineer btw" in the chat was gold lol

[ventic]

Things I learned from this:
- Promise callbacks are microtasks, not tasks
- "return" in generators is valid

[kkiller]

I remember the days when EcmaScript didn't even have proper classes. Back in my day, we used functions named in PascalCase and then prefaced calls to them with the "new" keyword.

[ucwolct]

God, I was laughing so hard when he was wrong in the last question 😂

[dipereira]

Ok thats it! Im taking javascrip proficiency out of my CV. thanks!

[alastor--radiodemon]

"you don't know javascript"

i know, i wanna keep it that way

[ruroruro]

25:49 I think prime is wrong here. I am pretty sure that this is how generator functions work in almost every language. Remember that the end of the function has an implicit empty return. If returned values in generators were also included in the iteration, then this generator

function* whatever() {
for (const elem of ["fist", "second", "last"]) {
yield elem
}
}

would produce "first", "second", "last", undefined and to get the obviously intended results of "first", "second", "last" you would have to do something like

function* whatever() {
for (const elem of ["fist", "second", "last"]) {
if (elem === "last") {
return elem
} else {
yield elem
}
}
}

which is just ridiculously stupid

[adjbutler]

GOTO considered harmful
JS considered deadly and dangerous

[coder_]

Maybe I should learn Blazor & just run C# in the browser instead.

[MaybeADragon]

Every day I thank the lord for not learning Javascript as my first language (visual basic chads rise up)

[sebastianwapniarski]

I actually switched smoothly from watching Anchorman 2 to Prime. The legend continues.

[ISKLEMMI]

This was fun!
IIFE - Immediately invoked function expression. I've heard it pronounced 'iffy' most of the time.

11:49 - I've definitely modified a few built-in prototypes in order to get Vue2 to work in an HTML Application / .hta file. mshta.exe uses an ancient JavaScript engine, so some monkey patching was absolutely required to get things to work at all.

[RandomGeometryDashStuff]

20:20 javascript does have Option, it's constructor for html <option> element

[_evillevi]

Lydia's slides are beautifully mind-blowing, does anyone know what she uses to make them?

[rikschaaf]

You know what would be interesting? A replay iterator that aside from next, return and throw also has a reset function. That way you don't have to keep a reference around to the original generator function. You can just reuse the current iterator. One that could also have niche usecases would be the caching replay iterator that, when reset, it doesn't have to recompute the original values, since it would have stored those values in a cache. That does defeat the purpose of generators somewhat, since they normally allow for a low memory footprint during iteration, but when caching you do still have that footprint. In such a case the only benefit would be is that you're fetching the values lazily, so you don't have to construct a full list of values before iterating over them.

[asdjzcx]

Senior dev vs junior interview questions

[FanatiQS]

Extra info about question 1. The prints for 4, 5 and 6 are sync in the javascript engine while 1 is queued in the engine. 5 is not implemented in the engine (not ecmascript) but still queues on the engines task queue. The setTimeout callback is added to the runtimes event loop and would not work at all in a pure javascript engine evaluation (it is a webAPI that requires a runtime). Writing my own super basic javascript runtime in C was great for learning how javascript runtimes work.

[size_t]

1:56 - looking at this, tells me: JS, you're drunk. Go home!

[tylermfdurden]

my_obj.__proto__ = "We're all adults here, I can modify whatever I want"