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Learn Node.js in less than an hour [Tutorial]
h
RohilPatel

Node.js Tutorial

What is the syntax like?

Well, everything you already know with JavaScript can be played here, except for the DOM, which if you don't know, includes interacting with a website.

For example we can do some basic console.logs() in Node.js

Ok, but why Node.js

Well, first off, if you want to know why not to use python, I won't say anything, but if you are here because you don't know the difference between the browser js, then continue on.

Node.js makes everything come together. It's a server, which basically controls a bunch of people. Chat rooms send a message to the server, which sends it to everyone else.

Sign in pages send your typed data and check a database to see if it exists.

But it all starts here...

Node.js has something called a module

4 concepts to remember about modules

  • A module must be imported
  • Modules make Node.js work not like browser js
  • Modules can make coding cleaner, resulting in more files and folders
  • You can make a module very easily

Ok, how do you import a module

Well lets use the old fashion way because repl needs to update to node 14 for other things.

Below is how you import a module

Can we import a module as an example?

Yeah ok, lets use the OS module

It can help with determining what module to use.

How do we make our own module?

Well modules are just js files that work with the server. Try going into module.js at this time, or making it if you are following by yourself.

In there, we added the following code:

As of right now these functions and variables are local to the file, so to make them public, you do the following after everything was declared. It is usually the last thing in a file.

Come back to index.js and import it

// Time to see our options:

We see this:

Our data is there, so now we can just get them with some dot notation.

There is an easier way to get the module though

Then use the function as follows

I really hope this tutorial helps!!

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Comments
hotnewtop
EpicGamer007

I would not call this a node tutorial. I would call it a module tutorial. You don't actually go over anything but module's

[deleted]

True, but luckily there was a module here I didn't actually know about.

RohilPatel
RayhanADev

Well, this isn’t really a NodeJS tutorial, you don’t go over anything that NodeJS is actually used for (Web Dev, App Launch, etc.) but instead just modules..

RohilPatel

Clickbait title lol. Definitely got u lmao @RayhanADev

RayhanADev

@RohilPatel lmao, fits perfectly with this xD.

RohilPatel

Lamo. I've never gotten 100+ upvotes on any of my posts lol @RayhanADev

RayhanADev

@RohilPatel I only got 50+ on the Repl Search Bar. That was it. All my other projects get like 5-20 upvotes. It makes somewhat sad xD.

RohilPatel

Lol, on average I get like 20, but my most has 73 I think @RayhanADev

RayhanADev

@RohilPatel nice! How long have you been on Repl.it anyways? You seem like an OG.

RohilPatel

Nah, I'm not lol. Only been here for like eh, a year and a half @RayhanADev

RayhanADev

@RohilPatel that at least 18 times longer than me also you go to the same school as Coder100?

RohilPatel

Yeah lol. He isn't as magical as he seems though lol in person, and to be fair, nor am I @RayhanADev

RayhanADev

@RohilPatel lmao, Repl is amazing like that isn’t it. I’m becoming scarily well-known for the less than month I’ve been here and irl nobody cares about me xD.

RohilPatel

Lolz. I'm working on a game called Amang Us. (Not a typo) @RayhanADev

RayhanADev

@RohilPatel hahahaha noice one! What’s it going to be about (please don’t say terminal among us I will cry)?

RohilPatel

Nonono, it's a website. I'm scared to make it multiplayer but I will do it due to socket.io resets but look here for now https://amang-us.rohilpatel.repl.co/# @RayhanADev

RayhanADev

@RohilPatel nice (enjoys clicking screen that does nothing) :ramen-blob:

RohilPatel
[deleted]

Congratulations! This tutorial now has more upvotes than the React tutorial! 😂

[deleted]

Great tuorial, @RohilPatel! I learned a lot that I didn't already know in the os module section.

Bookie0

Cool!

Also i think this comment supposed to be in the code block!

Tonight I plan to have it out, and if all this makes sense, go to here.

Btw there’s no link on the ‘here’, that intentional?

:)

RohilPatel

Yeah I wasn't feeling it. Also thanks for that error, I just made the llesson on the code and then did the md @Bookie0

TANMAYBAGADIA

Thx for this tutorial ,i will see this properly later but it's amazing . Take my upvote!!

RohilPatel
RohilPatel

@DynamicSquid do teachers at squid school make you learn from tutorials?

(Also do you have discord?)

firefish

@RohilPatel The only answer I know is to the latter question and no, he does not have discord. and also try checking timezones, (Mountain Time to be precise)

RohilPatel

Ok lol @firefish

RohilPatel

Did u know tutorials like tutorials

TsunamiOrSumth

Good job!

RohilPatel

Thanks! Upvote if you want, and I also saw on someone's post u were looking for a node tutorial, does this help? @tsunami21

TsunamiOrSumth
CodeLongAndPros

@RohilPatel I'm removing this, don't ask for upvotes.

Theboys619

We use Deno here.

RohilPatel

No yes @Theboys619

firefish

@RohilPatel you forgot the other way of importing:

Coder100

No, readFileSync is an identifier and this is not python, you got them reversed @firefish

RohilPatel

Yeah. @Coder100

RohilPatel

Python is on the opposite spectrum of JS lmao @Coder100

realTronsi

ha modules is also node's downfall.

RohilPatel

Yeah import is much better =/. Did u like the repl? @realTronsi

RohilPatel

Or I mean the tutorial @realTronsi

realTronsi

@RohilPatel not much content but yeah decent tutorial

RohilPatel

Yeah lol, upvote if u want. Is there anything you think I should make? I'm far more advanced than this tut @realTronsi

Theboys619

quick steps with functions, variables, loops, and if statements / switch statements. Maybe even JSON objects. @RohilPatel

realTronsi

@Theboys619 lol those are too beginner

Theboys619

i guess. @realTronsi

RohilPatel

Yea a little beginner, I'll probably teach ejs and data passing @realTronsi

realTronsi

@RohilPatel hm lol ok

RohilPatel

lolololololol @realTronsi

firefish

Yea a little beginner, I'll probably teach ejs and data passing @realTronsi

@RohilPatel I like to think I know a lot about node, but like what is ejs and data passing

realTronsi

@firefish ejs is just a rendering template, and I don't know what he means by data passing lol

firefish

@realTronsi I had a look at some ejs code, and pug looks more elegant than <%= stuff.

realTronsi

@firefish I never really used pug, but the ejs tag allows you to do expressions and stuff, not sure if pugjs is the same

firefish

@realTronsi like what kind of expressions, but I'm not exactly an expert at pugjs, @Coder100 is however

Coder100

pug js more like EJS @firefish

Coder100

Ok C tutorial when @firefish

realTronsi

@Coder100 ejs more like using websockets to send variables over and then replacing the innerHTML with the variable smort

realTronsi

@Coder100 Why do you need C tutorial

Coder100

Because C good @realTronsi

realTronsi

@Coder100 I thought you know C

firefish

@Coder100 C? YES POG POG trying to speak cookeylang POG POG C TUTORIAL POG POG

realTronsi

@firefish how much C do you know

firefish

@realTronsi moderate amount, here is most of my nkowledge concentrated into one repl: https://repl.it/@firefish/myMem

realTronsi

@firefish wait lol what is this for:

firefish

@realTronsi Index-out-of-range is not prohibited.

realTronsi

@firefish I know so why is that your function?

Coder100

POG POG POG POOGG @firefish

Coder100

that's why im writing it @realTronsi

firefish

@realTronsi random number generator

firefish

poogg? what in the world @Coder100

realTronsi

no but your random number generator is returning an invalid index, its going to seg fault no? @firefish

firefish

@realTronsi Aha, you see. It doesn't segfault because the index is only two places away from the end of the array, so there is stuff in accessible memory there. A SegFault occurs when you attempt to access memory that is inaccessible to your process, but the memory I am accessing is so close to the end of the array that it's probably reading the string passed to a printf call or something.

realTronsi

@firefish oh so it isn't random then though?

also thought this seg faulted but apparently this doesnt:

realTronsi

@firefish

interesting result

firefish

@realTronsi Well, the randomness occurs at compile-time, in the form of how to arrange the binary, rather than at runtime.

firefish

@realTronsi is 4195632 interesting at all?

realTronsi

@firefish what? I don't see how pseudorandomness can occur from compiling?

realTronsi

@firefish not sure what it comes from, doesn't change from manipulating the list

firefish

@realTronsi Ah, just realised. clang does things differently than to gcc.

firefish

@realTronsi I know, the clang version works as expected however the gcc one does not

firefish

@realTronsi @fuzzyastrocat Nightmare code: malloc bomb + fork bomb

realTronsi

@firefish what is that syntax highlighting ewww

firefish

@realTronsi my theme, thanks for reminding me that it is not normal syntax highlighting

firefish
realTronsi

@firefish ah yes perfection

fuzzyastrocat

@RohilPatel Please actually cover node's strength and main use case: writing server applications.

realTronsi

@fuzzyastrocat and also having simultaneously the worst and best package manager

RohilPatel

Yep I did @fuzzyastrocat

RohilPatel

Data passing is where you send something from the backend to the front end.

@realTronsi

realTronsi

oh, just cover templating engines instead then @RohilPatel

RohilPatel

yeah probably. @realTronsi

fuzzyastrocat

@RohilPatel Uh, where? All I see in the tutorial is modules.

RohilPatel

In the "ok, why NodeJs" @fuzzyastrocat

fuzzyastrocat

@RohilPatel The point of a tutorial is to explain how to do something. Nowhere in this tutorial does it explain anything about how to do server-side things.