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10 JavaScript concepts every Node developer must master

USMAN AWAN on October 05, 2024

Node.js has quickly become a standard for building web apps and systems software, thanks to its ability to leverage JavaScript on the back end. Pop...

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Serhiy • Oct 7

but why do you use var?

WORMSS • Oct 8

I am guessing someone who likes the nasty habit of hoisting. I would put money on them not being fans of Typescript.
I don't mind function hoisting, but I don't know of anyone who likes variable hoisting.
Though, I find people who use let for absolutely everything to be strange also.. I use const for everything unless I absolutely HAVE to use a reassigning variable, which is maybe only 1% of the time at most.

Jonathan DS • Oct 9

Is it hoisting or just global scope?

WORMSS • Oct 9

Hoisting. Because if you are inside another scope (closure for example) it's no longer globally available.

minoblue • Oct 14 • Edited

One usecase is when we want to access variable outside the block within the function.

function example() {
  if (true) {
    var x = 10;  // 'var' is function-scoped, not block-scoped
    let y = 20; // 'let' is block-scoped
  }
  console.log(x); // Accessing 'x' outside the 'if' block
  console.log(y); // ReferenceError: y is not defined
}

Adnan Babakan (he/him) • Oct 6

Good points to remember in JS. I really enjoyed reading it.

USMAN AWAN • Oct 6

Thank you very much 😊

shield8994 • Oct 7

Your article is well written. I am the operator of servbay. Can you promote our products? Our official website is servbay.com. If you are willing, we can give you some channel discounts.

USMAN AWAN • Oct 7

I would be an honour 😊😋

shield8994 • Oct 8

How can I contact you? Email?

Abid • Oct 8

Hi, is it not for windows users? I can not find any link for windows on your website.

Yurii Timofeev • Oct 8

Good advice... for 2014

Brad • Oct 7

I gotta point it out.

It seems like the code examples have inconsistent indentation? 🤔

Shahadat Hossain • Oct 8

Javascript and Node becoming more popular among developers. it is not bind only for web applications; we are building more complex applications like IOT, machine learning, chatbots, ect.
it is a really game changer for developer.

Friday candour • Oct 7

It's for beginners

WORMSS • Oct 8

Technically it's for 'everyone'.
Beginners will be learning about it, and for advanced people, it's a checkbox exercise to say "yep, I know these concepts".. It's not like, once you are past the beginners stage, you can forget these concepts..
It's always good to remember that async/await is sugar for Promises/then, and class declarations is sugar for prototype. It's good to remember that these are what is happening under the hood. Even if you don't touch these old ways anymore.

Mohammad Zeeshan • Dec 10

Absolutely agree! Understanding these concepts are the backbone of JavaScript and serve as a reminder of what’s happening under the hood. Even if advanced devs rarely use the 'old ways,' knowing them enhances debugging, performance optimization, and deepens overall JavaScript expertise. For beginners, it's a foundation to build on. Revisiting these basics is always worthwhile—it ensures we don’t just write code but truly understand how it works at its core.

Marc • Oct 7

advanced beginners ;-)

Tom Pereira • Oct 8

Shouldn't:

the CommonJS include syntax and the ES6 require syntax.

...read:

the CommonJS require syntax and the ES6 include syntax.

William Bernfield • Oct 10

Hello everyone, id live to get some help, Also how do you all feel about Quantum capabilities ? Early access

almogzur • Oct 7

Vary nice

ArsalanNury • Oct 8 • Edited

Thanks, I haven't seen anyone use IIFE in real programs. I think just Webpack and Babel are use it :-))))

I find rest operators the most useful section in this article my friend

José Pablo Ramírez Vargas • Oct 11

UMD modules are basically IIFE's. AngularJS had heavy use of IIFE's. Finally, CommonJS can see them used to encapsulate await syntax.

Alexander Borshak • Oct 9

Did you ever use jQuery? Aside of it, IIFE used often when you have to perform some actions during init stage of ESM module.

Robert Snedeker • Oct 7

Great article! I recently discovered the # private property/method thing in JS. But now that I use TS it's not something I use, still cool to see that JS is getting more OOP features though.

killer space • Nov 8

broo ,really this is way advanced for a beginner in js

USMAN AWAN • Nov 8

😊

RamR • Oct 8

nice post

Softwaredevelopmentinsights • Oct 10

Great insights on JS. It is very informative.

The Eagle 🦅 • Oct 9

I've had fun reading this article, thanks bro!

Rafa Rios • Oct 9

Nice article to bear in mind. Thanks for the clear examples

sachin kotian • Oct 9

nice article but try pasting code instead of screenshots

David Sabalete • Oct 11

Thank you!

retrop5 • Oct 10

The first I learnt / heard of curry functions and I love it, I am gonna keep using it extensively moving forward

Axorax • Oct 8

cool article :D

Vivek Garg • Oct 8

Love these insights keep sharing such valuable thoughts.

Adesh Tamrakar • Oct 7

This is going to be my everytime go-to revision list. Thanks.

USMAN AWAN • Oct 7

Glad to hear it 😊

Yair Nevet • Oct 8

Great post! However, it's a shame that the code examples are presented as images instead of regular text, as it makes it harder for readers to copy and test the code themselves.