The last video on javascript promises you'll ever need to watch
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- čas přidán 30. 08. 2022
- teaching about javascript promises
developer.mozilla.org/en-US/d...
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funny thing about await is that it works with any object that has a .then()/.catch() method, it doesn't have to be the built-in Promise class. This is pretty useful if one of your library you are using returns a pseudo-promise object or some sort of polyfill.
This video is excatly what title says, only video we need to understand promises. By far the best explanation I have ever seen.
I have seen your other videos also like subscriber refractor and I totally love it. Please keep up the good work.
I came across your channel a couple days ago, dude you made everything so simple to understand for me! Love the content bro. GODSPEED!
"Promise.reject" is useful when you want a rejected Promise to propagate further down the chain, instead of being immediately resolved.
This effectively allows us to change the behavior of Promise chaining so we can skip over ".then" methods that contains code which depends on the initial rejected Promise.
I was about request you to make a full video on promises after watching your short video on promises but here it is thank you!!
note that await works on not just promises, but anything with a `then` function, similar to how the $ syntax works on not just stores, but anything with a `subscribe` function
That’s cool to know, thanks for that info
Once again. A video right on time for the questions I’ve been having.
Learnt a lot! Thanks a ton.
Also, can you pls do a video on refresh tokens?
I learnt jwt from your video and realised there aren't many videos which explain what refresh toke ns are, and how to implement them.
Pls do a video on refresh toke if time permits.
Thanks again.
For a second I thought the video title said "The last video on javascript promises, i promise".
A good thing to mention is that instead of using Promise.all, you can initialize all your promises and await them where you need their resolved values.
So if you only need one of the values if a condition depending on another resolved value is true, you only need to await one value.
Amazing video dude! Have been following your content for a while. You make everything sound easy and approachable!
Truly the last video needed
what extention do you use for suggestions in IDE
founded it in description
😁😊
it would be really helpful if you made a video about the call stack
great video and great easter egg too.
Thanks a lot for your service.
my gratitude.
Would be Great to see tutorial about charts. I want to do coingecko clone but cant figure out how to do charts.
Great job!
Great video and explanation, thanks! A little nitpick, I'm sure it's helpful but the linting errors and red highlighting were pretty distracting to watch
I’ll turn them off next time
Why does my console always print, "Uncaught Reference error, Promise is not defined" even though I write the exact code you just taught? This promise thing is just eating my mind currently. I wrote promise code in vs code, in chrome (snippet), and even then the output is the same. I can't figure out why!
This implementation save value, but do not have state, right? So we can resolve internal promise(in wrap) over again and return another wrapped 'promise'. new Promise makes an object, so where this (res,rej)=>{res(val)}, I mean executor where it will be store? In closure? It execute immediately, but res(val) always return new Promise? Urphh, complicated!
*DOUBT* : Does promises run a certain set of codes synchronously while allowing other codes to run asynchronously? What I am trying to ask is if a code depends on the result of a time consuming expression, it can be wrapped in promises while those that does not require the result of the expression can run asynchronously?
i might be wrong but i think first c# has introduced async await keywords and the workflow.
Maybe idk, this isn’t a video on c#
@@WebDevCody oh i thought it was a python video.
@@gordonfreimann ah honest mistake, nah this was a video about go
from inside this._wrap method you're returning an function with a value as an argument and storing the returned result inside this._then but from where you're calling that function and passing that value can you please explain...
every async function will return a promise, so you can chain .then or .catch after the function call
I regret not mentioning that. I guess I’ll need one more video 😂
@@WebDevCody will be the last last video then ;)
i actually like the fact you can add a catch to every promise that you await inside async function and in there log the actual error and throw it again with self defined error message to send it directly to the outer catch
Good job babe!!
Babe!?
@@mikopiko she is his wife
@@YourExecellency bahaha y’all thought I was his stalker huh 😏 thanks for lookin out for him
Do you have any plans on doing projects with nodejs and SQL, orm ?
I often make videos using prisma which is an orm for sql
@@WebDevCody oh really i didn't know that. I will search for those tutorials. Is there any specific playlist ?
Happy Coding ... 👍
"The last video on javascript promises you'll ever need to watch"
Do you.......
PROMISE?
I'll see myself out now.
WHAT IS THAT ERROR HIGHLIGHT TEXT PLUGIN NAME?
Error lens
@@WebDevCody Ty, and sorry for caps!
24 minutes watched
48
96@@WebDevCody
You promise?
No promises
@@WebDevCody Promise rejected!
@@whisky8496 it’s all settled then
Promise.allSettled() is good for use cases where you have several promises and your not dependant on all of them resolving, but you still want the ones that did resolve. Promise.all() will reject if one rejects but allSettled will continue even if one fails.
Edit: Could you do a video on your linting or zsh, basically your coding setup.
Great work man, you should consider PromiseAllSettled, is pretty useful.
I think I've used that maybe once or twice, but yeah I could see it's usecase
//eslint-disable no-unused-vars
Great video!