Show HN: I'm 12, learning JS, and wrote Wolfram's cellular automaton in Node

> Again, thank you so much for taking the time to review my code. I really enjoyed your feedback.

Whatever you do, hold on to that. Never be mad about feedback just try your best to understand it, and if it's wrong explain yourself without getting frustrated, this is worth more than a dozen senior developers who explode at feedback (I would argue they're junior developers :) and you will have a wonderful career. Also look for good mentors, and don't be afraid to ask questions about direct feedback, if you didn't understand something he said just ask (this becomes an immediate learning opportunity and you will be better off for it), even if he doesn't get to answer, someone else might. This is a field where learning is endless, you will always learn something new as a software developer, new platforms are made all the time to be programmed on / with.

Having soft skills[0] will be the biggest asset you can have as a software developer, whether you do it for money or just for fun, if you have to collaborate in the open you will need to communicate with others. Nothing breaks a team like terrible communication and someone who rejects feedback out of pride.

[0]: https://en.wikipedia.org/wiki/Soft_skills

So glad to hear, Liam! Was a pleasure to put it together.

Good luck, and feel free to reach out if you get stuck on anything.

This whole interaction is really reaffirming my faith in humanity. You guys are awesome!

Liam -- this response is just as impressive as the code that you wrote. You're obviously very smart, but that isn't good enough on its own. I've seen very-smart people who aren't open to critique, who get defensive rather than take the opportunity to learn new things. They don't get very far in life. On the other hand, the attitude you're showing here is tremendously valuable, and will serve you incredibly well throughout life. Never let yourself grow out of it!

Drive-by code reviews (and maybe other types of annotated "audits", like for security bugs) would be a nice feature source repo sites might consider adding one day. It seems like a missing practice in open source development, code reviews (if any) are done by active developers once on check-in/merge acceptance. But as we see here code reviews can be a useful way to pay it forward too, not just new code / issue fixes, and done out-of-band there's no pressure to bow to the reviewer just to get something in; you can just have conversations and learn things.

The video format is a nice twist, in my distributed teams sometimes we've done "code review meetings" for some changes that are rather involved to capture some of the benefits of in-person / video code reviews.

Thanks for the kind words! Will definitely consider.

Seconded. Do it. :-)

Let us know here if you are planning to do it :)

Just registered to +1 this

+1 Please and thank you

+1 count me in

+1

+1

+1

+1

+1

+1, reminds me of Destroy All Software

Thanks for the edits! I can't change the video, but did mention that both of those lines are a little clunky. I did update the gist though! Much cleaner.

I like to break expressions across multiple lines, and line up any patterns that are repeated, so your eye can easily scan up and down and obviously see what's the same, and what's different.

For example, instead of:

    var length = Math.sqrt((x * x) + (y * y));

You can go:

    var length = Math.sqrt((x * x) +
                           (y * y));

That way you can see the similarity of squaring x, and squaring y. But breaking up the multiplications because they repeat the x's and y's would be taking it too far -- it always requires balance and thinking about how can I communicate my intent and the SHAPE of the problem I'm solving.

You can also use indentation and formatting to bring out and make obvious other two-dimensional patterns and regularities, especially with two-dimensional cellular automata and graphics code.

There are some examples of that technique in my 2D cellular automata machine code. (There's a lot of code, so don't be overwhelmed, since I've been working on that since around 1985 or so. So never give up and just stick to it! You don't need to understand the code, which is pretty esoteric, just notice the patterns.)

https://github.com/SimHacker/CAM6/blob/master/javascript/CAM...

                        // Load the right two columns of the 3x3 window.
                        n  = cells[cellIndex - nextCol - nextRow];  ne = cells[cellIndex - nextRow];
                        c  = cells[cellIndex - nextCol          ];  e  = cells[cellIndex          ];
                        s  = cells[cellIndex - nextCol + nextRow];  se = cells[cellIndex + nextRow];

[...]

                            // Scroll the 3x3 window to the right, scrolling the middle and right
                            // columns to the left, then scooping up three new cells from the right
                            // leading edge.
                            nw = n;  n = ne;  ne = cells[cellIndex + nextCol - nextRow];
                            w  = c;  c =  e;  e  = cells[cellIndex + nextCol          ];
                            sw = s;  s = se;  se = cells[cellIndex + nextCol + nextRow];

[...]

                            var sum8 =
                                    (nw & 1) + (n & 1) + (ne & 1) +
                                    (w  & 1) +           (e  & 1) +
                                    (sw & 1) + (s & 1) + (se & 1);

[...]

                                var tableIndex =
                                    (((c         >> plane) & 0x03) <<  0) |
                                    (((e         >> plane) & 0x03) <<  2) |
                                    (((w         >> plane) & 0x03) <<  4) |
                                    (((s         >> plane) & 0x03) <<  6) |
                                    (((n         >> plane) & 0x03) <<  8) |
                                    (((cellX             ) & 0x01) << 10) |
                                    (((cellY             ) & 0x01) << 11) |
                                    (((phaseTime         ) & 0x01) << 12) |
                                    (((plane     >> 1    ) & 0x03) << 13);

[...]

When the sub-expressions won't fit on one line, you can still use indentation to help the reader understand the spatial patterns:

                            error +=
                                (nw * kernelBytes[4 - kernelDown - kernelRight]) +
                                    (n  * kernelBytes[4 - kernelDown]) +
                                        (ne * kernelBytes[4 - kernelDown + kernelRight]) +
                                (w  * kernelBytes[4 - kernelRight]) +
                                    (c  * kernelBytes[4]) +
                                        (e  * kernelBytes[4 + kernelRight]) +
                                (sw * kernelBytes[4 + kernelDown - kernelRight]) +
                                    (s  * kernelBytes[4 + kernelDown]) +
                                        (se * kernelBytes[4 + kernelDown + kernelRight]) +
                                frob;

But that would probably be more readable if I used intermediate variables for the kernelBytes[...] expressions, gave them descriptive names matching their corresponding directions, and lined up all their calculations so you could see the similarities and differences, because right now all the kernleBytes[4 +/- kernelDown +/- kernelRight] expressions are jumbled around horizontally, when they could be lined up nicely by themselves if they weren't interleaved with the n/s/e/w/ne/nw/sw/se multiplications. (I'll leave that improvement as an exercise for the reader. ;)

The point is you want to vertically line up as many of the repeated letters and symbols in nice neat columns as possible, so that your eye can easily see which are the same, and the ones that aren't stand out obviously so you can ignore all the same things and focus on the differences. (Which are typically variations like +/-, sin/cos, x/y/z, -1/0/1, nw/n/ne/w/c/e/sw/s/se, and longer series of names and numbers. Whatever changes should stick out visually, and be lined up and grouped together so your eyes can scan over them!)

That not only helps other people understand your code, but it also helps you be sure that you wrote the right thing, what you actually meant, instead of making an easy to miss typo.

The difficulty of reading you own code, which is HARD even for professional programmers, is that you usually see what you MEANT to write, not what you actually wrote. That's why it's so important to get other people to read your code, and to read other people's code, like pair programming and code reviews, or even explaining it to a duck.

https://en.wikipedia.org/wiki/Rubber_duck_debugging

It takes a lot more effort and concentration to slow down and look at what's actually there, instead of what you want to be there. (That's true for many aspects of life...)

Thanks! I really enjoyed making it. HN has been such a huge part of my life over that last ~10 years that it's truly the least I could do.

Thank you, much appreciated!

Thanks, glad you enjoyed it! And like another person already responded, this is vim with a split pane where the right pane is a `:terminal` (a relatively new feature of vim... though prior to that I would have just used tmux).

Highlighting searches is enabled with `:set hlsearch`, and you can search for whatever word is under the cursor with ``. So I just type and it highlights all of the matching words. Nothing too magical!

This is vim.

Startup Idea: Start a slack/discord group for aspiring students between the ages of [pick your age range, say (8-18)] and start a mentoring/support group with these like-minds...

You'll learn, build relationships and some of you will go off and found companies together.

> there are a lot of projects that I don't finish...

You and me both. :)

sine and cosine last year? Now I want to know what your parents are feeding you!!! ;)

I've got a 10 year old who's been making a lot of stuff in Scratch since he was 6. I've been trying to think of how to phase him over to less limited languages and wasn't aware of blocklike.js, so thank you for that idea.

Having a lot of projects that you don't finish is completely normal, so don't worry about that.

Is this serious? I started programming around 9 or 10 on a Commodore 64. I would go to the local library to get programming books for it. Now you can hit F12 in your browser and get a powerful console into JS. JS is fine, encourage the thirst for knowledge.

This kid is practicing calculus at 12 years old. He will be able to handle a package manager.

Isn't Liam's project proof that you don't need any complicated JS tooling?

A simple `node index.js` can go really far.

You need none of those things to get started with JS development

It’s still perfectly possible to just create a html document, shove in a script tag, and start developing

And if you want to use packages from the npm ecosystem you can easily use https://unpkg.com/

The only thing you need to learn programming with JS is a text editor and some rudimentary HTML knowledge.

Everything else is unnecessary, at least as far as the programming language itself is concerned.

I second this. Knowing why something is better to use is most likely learned through doing it a worse way first.

In fact this "you should never code FizzBuzz yourself, just use util.FizzBuzz(n) to print the first n iterations" mentality probably contributes to the surprising number of software developers who can't code.

This project explicitly says Node. But in any case, these days I generally recommend using Babel to transpile the newer JS to browser friendly JS as the productivity and readability improvements in newer versions of JS are worth the effort to me to set up the babel build step.

Older devices running node?

Not even businesses doesn't (and shouldn't) care for older devices when it doesn't make economic sense -- even less so a fun learning project.

The code would fail to run on older devices without transpiling wnyway.

> My dad showed me git last week.

Anyone else miss learning this quickly?

In all seriousness, congrats. Keep at it. There is always something else to learn. It's the career that never stops giving.

That's pretty quick!

Do you have any plans for future projects? Maybe a simple place where you could chart your progress?

I think one of my favorite uses of cellular automata besides conway's game of life (if you are interested in it) is modeling simple fluid mechanics (water flowing from place to place) in games like dwarf fortress http://www.bay12games.com/dwarves/

That's so freaking cool. Git rocks, and I remember how psyched I was when I learned about it. What's your next project?

> My dad showed me git

Cheater! :) Seriously though, great work. I started around your age (which I guess means I've been coding for half my life at this point.) Keep challenging yourself with new and interesting projects and you're going to learn a lot and have a lot of fun.

writeln(chr(7)) ?

or something more (e.g. playing different frequencies to sound like the happy birthday song)?

Related, and good fun for kids of all ages (first did something like this on my earliest home computer [1]):

Play the piano on your computer with Python:

https://jugad2.blogspot.com/2013/04/play-piano-on-your-compu...

[1] Lissajous hippo, retrocomputing and the IBM PC Jr.:

https://jugad2.blogspot.com/2012/09/lissajous-hippo.html

Western classic music fans may find the comments on that post interesting - stuff about octaves and frequencies.

+1. Reading your answer made me think you were talking about me. Except I had a TI99/4A, and "Daaaad" was my real google. My circles were probably slower and more pixelated

How about for a 32 year old who is just learning JavaScript and comes across this repo? Age has nothing to do with it.

Perhaps for himself when he's thirteen or fourteen and wants to refactor

Why not learn good programming practices at an early age?

:)

9. Use webpack!

That's a good question. I left that intentionally broad so as not to prescribe a certain type of learning system or self-education.

There's a lot of ways to learn anything, but I would say that the first step is pursuing a variety of subjects that you find interesting, and even some you think are boring. A lot of seemingly boring things I've found turn out to be quite fascinating when it comes down to it. (e.g. database design)

Over time, you will pick things up, and put them back down. You will return to some, and stay away from others, but eventually you will build a repertoire of knowledge and experience in a variety of different fields. I would also bet that at least one subject will interest you so much that you keep coming back and in which you will ultimately develop expertise.

Experimentation is the name of the game!

I work in cloud, and one of the things I look for when recruiting solution architects -- another role where broad is a pre-requisite and some narrow depth is expected -- is systems design skills. Besides whatever you study and learn how to do as a programmer. these days it's not often commercially applicable unless you know how to make it run well in the cloud, with all the caveats that apply.

Among the things that aren't common knowledge among basement programmers: network configuration (VPCs, load balancing, CDNs, security), security/IAM, non-relational datastores, ML model development & training, and the list goes on and on and on (microservices & containers, devops, serverless, advanced logging/monitoring & problem solving, high availability, HPC/grid, blockchain, and oh so much more.

The point I'm trying to make is that you can become a T shaped programmer by continuing to study and learn various programming skills, but you may want to alternatively consider becoming broad in ways that expand your value beyond just coding.

A phrase I came up with that I like more than "T-shaped" is "molecular skillset". A chemist would probably laugh at me but I think of it as developing seemingly independent skills (molecules <--> skills, experience, knowledge...) that end up forming bonds with other skills, sometimes in surprising ways, that together prove really powerful and can bond up even further. "T" and other tree/tendril-ish shapes are then just special cases of different bond arrangements. You can acquire skills haphazardly (though as a serial dabbler I'd caution against actively pursuing the dabbler's path without a ton of introspection), you can also take the efficient road like a university sequence where most skills are visible and have unsurprising connections to the next skills. You might have to take some seemingly unrelated course too, but you can look at those optimistically as another potential source of surprising bonds. Duds are of course possible -- I have some useless things in my brain that I don't think will ever connect with anything useful, at best they might aid in social signaling one day. (A lot of education is just signaling to show you can talk about a lot of stuff...)

Trivial example: at some point around age 17 I installed Gentoo successfully and learned a lot about gnu/linux (and some bsd) in the process. Lots of little skills formed and connected, and they continue connecting with other things to this day. Got my initial hook on vim then. Saw how nicely colorized my terminal prompt was and that opened the door to many bash customizations. One of the skills I had to learn was to understand how hard drives worked (at least to the ability to successfully partition, format, and boot them -- I did accidentally wipe a windows xp partition the first time). Some years later (age 20?) I had accidentally rm'd a couple weeks of java work without having committed it yet. But prior knowledge of the system let me know the data was still there, and I was able to recover it by scanning the disk device partition directly for the bytes. (Ended up using "grope.tcl" referenced here http://wiki.yak.net/592 which was a lot more efficient than what I was making.)

With that said, it can also have the opposite effect. Success in online interactions at such an age gave me the confidence I needed to be successful in irl interactions.

> I virtually skipped having social interactions

That was me, too. It was a trade-off for me. I was reading Hawking in primary school and there was no one to talk to, so I was feeling lonely.

Programming was my lifesaving straw, but I don't wish any kid the kind of isolation that I've felt in my youth. I had to learn many of the social stuff later in life so it evens out IMO.

Oh definitely I agree. Gotta find that middle path.

No, it's not the same as doing that for women or black people.

People lie about their gifted child to get them exposure all the time. People doing that with art comes to mind. Or even just a parent doing assignments for their kid.

You're not being creative enough if you can't imagine a world in which someone would lie about something on the internet for attention.

OP is actually a dog

Mathematicians got it directly from cartography. A “map” “maps” points from one set of coordinates to another, for example when you want to plot latitude and longitude on a flat paper.

I expect ideas of mapping functions are only a couple of hundred years old at most, and really quite obscure to most people who are just familiar with the concept of 'maps' and 'mapping' things 'out'.

In functional programming I understand map as just a clone and convert operation. I noticed C++ has a 'map' data structure which is most suitable for associating references. A C++ map is not suitable for storing positions in space.

It's really not all that unusual. History is littered with amazing minds that accomplished tremendous things well before adulthood. The modern fiction that humans are useless until adulthood is one we have to construct by force, through active neglect of education, denigration of intellectual pursuits ('Go outside! Get a life! Do anything else but read or sit and think!'), and adamant insistence that it is normal to be ignorant and incapable until adulthood. Pascal recognized his triangle as a youth, Gauss was similarly known for early feats, etc. Those are just accidents of history, mostly, that they are remembered. The actual number of fertile and productive minds is doubtlessly orders of magnitude higher. It's only through diligent refusal to believe, or to tolerate the notion that maybe we should have expected a bit more of ourselves in our own youth, that we can keep up seeing intellectual achievements of the young as an unusual occurrence.

Catching the disease of cellular automata isn’t a good thing. Fredkin was also affected. This young person has many years to do useful things.

What about those of us in the 3rd group - started late and have to work hard at it!

Or all the 42 year olds, ahem, who are currently learning JS/Node/React. :-/

Ah yes, you are right. Got those mixed up.

Send a request ...

On the internet, nobody knows your a dog.

Nice work dude!

11 year olds follow the rules!

From a guy that was doing cool things with a computer at age 12 but instead of starting to workout at age 12, started at age 18. Any age is good to start working out but sooner is better.

Going to be honest, when I was 14 and learning to program, I quickly learned how shitty and harsh the internet can be, especially the types that frequented forums.

Guys, I think you should ALL calm down and stop playing SJW. He simply stated that he doubts the kid wrote the code. Since when having a doubt is considered BULLYING??? Did he insulted the kid? Did he used a slur against him? No. He expressed his legit and reasonable doubt.

So please turn on your neurons and stop playing mother hen and SJW ok?

Being skeptical is a right we all have to take advantage of and since it has been made in a respectful way, there are no reasons why attacking the user in the way you all did.

This politically correct thing is slipping thru your fingers and out of your control of you REALLY and SERIOUSLY think that expressing a legit doubt is considered an act of bullying. Ponder about that.

No it's not awful. People will doubt him sometime, and it's better to learn how to deal with that and gain a life skill rather than expecting every person to be sweet and supporting.

There are some kids who just goes on game chats to mess with others, play loud music, bully them, grief them etc. They are usually around 12 years old to 16 years old. I'm sure these things are not new to this kid.

Welcome to the planet.

The good style might be a result of using ESLint.

The OP opened the door with fishing for positive ageism, and then that person responded with negative ageism.

The taijitu is whole.

Sorry, but this is still totally relevant: http://www.coding2learn.org/blog/2013/07/29/kids-cant-use-co...

My intent is less "code structure", and more "most of the pieces you need to make a Node project also work in the browser". Imports/exports and Parcel would get liamilan most of the way towards being able to do...

   if (window) {
     document.write(...)
   } else {
     console.log(..)
   }

...and have it just work, without having to write everything twice.

Hell, I'm 50 and its the last thing I need.

Everybody needs a build toolchain eventually, and learning it early saves the eventual "this webpage has become a 5000-line JS file and it's incredibly unwieldy to maintain" hassle with a more complicated project.

The fact that it's dead simple is the point of the recommendation. It gives an opportunity to learn the tool with the bare minimum of moving parts involved.