Roblox Creates React In Lua

[@glauco_rocha]

HERE WE GO, LADS: LUA MENTIONED

[@1apostoli]

BRAZIL MENTIONED BRAZIL MENTIONED

[@randerins]

LUINHA DO MEU CORASSEUN

[@thui6253]

brazil tangentially mentioned

[@thingsiplay]

GO MENTIONED

[@alejandroalzatesanchez]

:D

[@mxruben81]

Roblox actually did this a long time ago. It's mainly used to write ui code in their engine. Afaik they aren't actually using lua for their website? Also, fun fact, their fork of lua (called luau) has a type system and some other goodies such as compound assignment and continue statements in loops. It does this while still staying simple. Best part is that it's open source and you can use it freely (although their c API documentation is lacking). I haven't wanted to go back to vanilla lua since.

[@BiffBish]

Luau is great, I’ve written tools for Unreal Engine that help integrate gameplay elements into lua for easier user generated content, their type system is more then enough for 99% of use cases

[@v0xl]

the only reason I'm still not using luau in my stuff is that it lacks jit

[@mxruben81]

@@v0xl it actually does have something like jit that they're calling native codegen. From my tests, its performance lands about in the middle between lua and luajit. It does especially good if there is a lot of math involved. The native codegen feature is still pretty new though and they've just started using type info for optimizations so I imagine it'll get a lot faster.

[@Hyllested_]

Additionally, Luau has backwards compatibility with Lua! So any program that the Lua interpreter can run, the Luau interpreter will also run.

[@hedwig7s]

@@Hyllested_ * Specifically Lua 5.1

[@aarond309]

Lua’s length operator is actually even *more special* than you think. #tbl returns the length of the table *only* when the table is a “sequence” (ie contains sequential keys only). If any keys are non-sequential (think nils or strings), the result of #tbl is undefined and up to implementations.

[@marcusly3497]

Not undefined. It only counts things in the array portion. It uses a binary search, that is why it messes up at non sequential indices

[@aarond309]

@@marcusly3497 Apparently this has been better defined since older lua versions; but according to the lua 5.4 Reference Manual Section 3.4.7 (I'd put a link, but KZbin): "The length operator applied on a table returns a border in that table... a border is any positive integer index present in the table that is followed by an absent index, plus two limit cases: zero, when index 1 is absent; and the maximum value for an integer, when that index is present. Note that keys that are not positive integers do not interfere with borders... When t is not a sequence, #t can return any of its borders. (The exact one depends on details of the internal representation of the table, which in turn can depend on how the table was populated and the memory addresses of its non-numeric keys.)" So, while non-integer keys no longer produce undefined results, when your table has a hole, any one of the values followed by nil are legally allowed to be returned by the length operator. The "array section" and "hash section" are implementation details and are *not* present in the specification.

[@isodoubIet]

This has to be the worst single feature I've ever seen in any non-joke language

[@RedstonekPL]

man i thought i wrote this comment

[@sas408]

Yes, but still you can implement something like table.Count and also it got metatables to customize lua whatever you want. The goal of lua is to provide you some basement under few kilobytes of code

[@RenderingUser]

man, if only roblox didnt permaban linux as a platform

[@realskyquest]

I feel you bro, the current option is to use waydroid the gapps ofc to not suffer from binary types. But still pc specific games are blocked

[@jaydeep-p]

Who is playing roblox on Linux?

[@realskyquest]

@jaydeep-p not sure, there are some people on reddit talking about this. But I don't play on linux

[@RenderingUser]

@@jaydeep-p I used to play occasionally

[@trustytrojan]

used to play but once i stopped getting away from gaming entirely, i have no urge to boot windows to play roblox. i wont play it until someone gets the 2016 client source to compile on linux

[@berkormanli]

As a part-time fun based Lua developer, there is a beautiful thing in Lua called Metatable and Metamethods. Since Lua lacks classes, these two can mimic some of object oriented behavior. You can easily change a table's behavior by using those metamethods. If you want to create an Array class, you would change the _newindex metamethod (this will be called when there is an assignment, _index will be called when there is an access.) to count its length and also set it with rawset() method. You can also change the behavior of the length operator (#). Using Lua made me furious because it lacks so many things like data structures and some algorithms/functionality you would consider a standard but later on after spending some time trying to implement things, this made me actually realize how much someone can forget the basics because using a library is a lot easier. It is a crazy small and core language that can be a lot more by using what it provides.

[@triducal]

as a roblox dev react-lua is extremely useful for creating declaritive ui functionality and makes it alot easier to put together large projects.

[@ARandomUserOfThisWorld]

Not _necessary_ but very much appreciated + it’s a nice QOL + if you have a big project, it’s going to be so much easier

[@griffitaj]

You can learn Lua in less than a day. It has the bare minimal set of semantics needed for a language. One collection type, tables. Strings as atoms (think Erlang), so they are blazingly fast to compare.

[@georgerogers1166]

Would be even better if they had both Strings and Symbols.

[@amargasaurus5337]

do remember to remember what things are references and which are values and ints silently floatify if you're not careful those got my noob bottoms in trouble a few times, but it does pack a lot of power in little syntax!

[@bullpup1337]

sorry, but after reading the lua book for 5.3, I have to say it will take me much longer to become proficient in lua. Its not quite as simple as it seems.

[@griffitaj]

@@bullpup1337 For proficiency with just using lua you only need Chapter 3 of the book + reference for any libraries you are using. I agree that if you want to write lua modules in c it does take some time as each version of the lua API has its own subtleties.

[@bullpup1337]

@@griffitaj We might be talking about a different book, I mean programming in lua by the inventor (ierusalimschy). Just finished chapter 18 on generators and iterators, and I have not even gotten to coroutines yet. There is a lot more than I thought to the language.

[@bharatsnair]

Redis has embedded Lua, which lets you write Lua scripts that are atomic. Fun language to work with.

[@harleyspeedthrust4013]

ive seen this in some of our production code at work but I've never had to work with it. lua really is a great embedded scripting language.

[@fcktyshawn]

i recommend everyone learn roblox lua. the best introduction to programming for kids. i started with roblox lua in 6th grade and now i'm a 22 computer technician and hobbyist programmer.

[@honkhonk8009]

lol same here. I learnt C to fuck around with arduinos back in grade 5 but i thought lua was really similar just cus i would be using C as a glorified scripting language anyways. Highkey lua is underrated asf. Its so much nicer to use than python and javascript. Im surprised its not used more

[@incription]

ccrazy because i went from computer technition to roblox dev at 22

[@itsyaboivoid]

​@@honkhonk8009It's not used as much because Lua is used more in game development

[@omri9325]

You better hope the cricket won't DMCA this video, he seems determined.

[@JanJozefo]

Who?

[@frost54311]

@@JanJozefo put headphones on, and you'll hear a cricket sound in the background

[@JanJozefo]

​@@frost54311 lmao I hear it now. I always listen to these on my phone's speakers

[@MatiasKiviniemi]

Great thing about Lua is that there's zero time wasted on architectual formalities, you just start coding. And since there's really no bad ways of solving something, results are never too horrible. Good developers make great code (as always), average coders make ok code and even bad ones make better code than in more complex environments with more options to screw yourself. I've done multiple-inheritance OO in lua, had every game object contained a Components-table where you could inject any game feature. Game loop iterated through those and class methods just had object as first param.

[@Nadi_Games]

I've been using lua for almost 20 years: World of Warcraft addons , it's lua 😉 Iirc, it was the 1st time I used it. And Prime is right, lua is a fantastic language. Even the name is cool, and poetic. Lua is not an acronym, it just means moon in portuguese. 🌔

[@johnathanrhoades7751]

I’m currently reading the “Programming in Lua” book. It’s interesting for sure. Looking at it for writing a neovim plugin.

[@lolgreek123]

It is used to make GUI for Roblox games

[@jboss1073]

WHY NOT TCL? IT IS A THOUSAND BILLION TIMES EASIER!

[@criptych]

@@jboss1073 That was sarcasm, right? … Right?

[@stefanalecu9532]

​​@@jboss1073 as much as I love Tcl and I use it for everything that requires quick GUIs and scripts... The team *really* has to get a better theme for Unix. And a lot of tooling to at least try and convince people to give it a shot. It is a great language buried in obscurity (unless you work in EDA or use Expect or Tkinter) Sidenote: it should be possible to straight up port Tk to the web (after all, we can use Emscripten and have the entire language run in the browser, which is lightweight enough to be viable)

[@fueledbycoffee583]

actually all game logic is written in lua. Both UI and and game logic

[@mikec2845]

yeah the entire game is written in lua, not just ui

[@justin4911]

The funny part about Prime's "don't use a DSL, use Lua" is that Roberto Ierusalimschy, the BDFL of Lua, teaches a MOOC focused on creating small languages using Lua.

[@lwinklly]

Wasn't the whole idea of Lua based on a DSL called Sol as well?

[@inconnn]

lua on roblox is how i got into programming in the first place, so i have a soft-spot in my heart for lua

[@dareisaysneed]

you should implement preemptive coroutines/goroutines in vanilla lua with the debug library

[@EdmondDantèsDE]

cursed title

[@thingsiplay]

i read that as cursed titties

[@felipheallef]

Brazil mentioned!

[@Tony-dp1rl]

There are some incredibly profitable services written entirely in LUA. I am not experienced with it, but I know some companies make a lot of money using it.

[@iddiiddrisu5971]

OMG!!! My embedded systems just got a new frontend. React-lua!!! Let's go!!!

[@Rugg-qk4pl]

HTML/CSS based UI is so much better than the UI libraries most games engines have built in. So awesome

[@XxZeldaxXXxLinkxX]

It should be a universal standard at this point. Every other ui system just feels so clunky

[@devcomptrickshots4136]

This is a bit misinformed. First off, Roblox uses luau (not lua), luau is a typed and much more performant lua alternative. The codebases were old, and before GitHub support luau syntax highlighting, and hence they're marked as lua. Secondly, Roblox's frontend is *not* written in luau, these libraries are equivalents to JS libraries for writing games on their platform. The only bit of frontend which uses this is their desktop app (LuaApp). EDIT: I noticed some people ask about typed arrays, and doc comments and a standard library; the luau community has made things for this. Typed arrays are built into luau types, doc comments are powered by moonwave (it's similar to rustdoc, it generates a doc site from comments for you) and lune is a runtime which implements a complete, lightweight, and fast standard library for it.

[@lwinklly]

holy crack, new dev comp wisdom just dropped

[@devcomptrickshots4136]

@@lwinklly hi

[@ardwetha]

If you are annoyed by 1 base indexing just make a function which adds one.

[@aaravsethi6070]

Roblox has a lot of compilers, they own a JS & TS compiler for porting existing libraries (Polyfill), one employee made a compiler for TS for making games. Btw Roblox used to have React which has existed for multiple years, their React-lua is only for employees coming from Meta that got used everywhere.

[@brssnkl]

You can expose native functions to js via JavaScript Interface on both iOS and Android. I think even react native is doing that after so many years. You can do updatable js in iOS/Android in a day as well.

[@SamWhitlock]

I've always used Lua as the "embedded scripting language" to coordinate the logic in most of my projects. I have an IRC server that basically does all of the logic in Lua (and it just wires up the message handler pipelines and then calls Lua from C++). I've also used it in a network controller to essentially do a corporate version of Tailscale. Extremely easy to embed (Sol3 is great in C++, though it's getting to be borderline abandonware).

[@apexfossa]

Lua is fun, can make cool scripts with it in roblox

[@LiveErrors]

Shout-out to EmmyLua btw If I'm not mistaken they are the ones who innovated the type checking lsp functionality that SumNeko uses Might be wrong

[@palmberry5576]

They are the one that made the annotations, but I think the type system is being completely rewritten (and still probably will be too weak to document the cc tweaked api lol)

[@ismichi]

i chose lua to be my first language as i finally return to learning this stuff pretty much 'cause it's so simplistic lol

[@henningerhenningstone691]

Lua is so embeddable that it has risen to the proverbial Doom in "can it run Doom" of programming languages. If there is anything that I can reasonably embed Lua in, I will :D

[@zoltannyikos7039]

You can also embed Ruby either the whole regular version or mruby which is a smaller, easier to use version specifically built for this embedding usecase.

[@maxbd2618]

The length operator is changed in later versions, but all the cool kids use 5.1 ig

[@DanktownBunny]

To bypass the #a problem, Garry's Mod gLua has table.Count(a) that iterates over the table to get the correct amount. My favorite part of lua is the fact that all tables are basically dictionaries, you can shove any data you want into them. Even a function could be a key!

[@hallo7053]

idk that is not really a bypass, you can just use a for loop instead, but in the end imo it does not really matter anyway. I don't think I have ever used mixed dictionary and array in lua

[@palmberry5576]

@@hallo7053yeah, the most mixing I have ever done would maybe be string | table or false | something

[@jonatasbaldan]

Is Lua itself getting updates? The interpreter shows "1994~2012".

[@GerardLementec]

it is but in all honesty lua 5.1 or luajit are enough and is what is usually used in most projects

[@arson5304]

roblox forked their own version of lua and is updating that, it's called luau

[@_garicas]

Lua 5.1 was (and still is) the most popular version due all its features and still being really simple, also when LuaJIT was developed, it was based on Lua 5.1 and still is. There's Lua 5.4.6 which release data was 2023-05-02 (in the official Lua website), but people use version 5.1 a lot also to not break compatibility in some cases

[@boblol1465]

lua5.4 exists but lua5.1 and luajit are the most popular versions luajit is based off lua5.1 and includes minor improvements from versions in the future

[@Shaar_]

use luajit it's the better version for me

[@Bloky.]

QuickJS is just as easy to embed as Lua. Although when you start toying with async you will need an event loop

[@hri7566]

i forced roblox-ts to write code for computercraft instead, it's fairly annoying to work with, but it's better than bare untyped lua

[@askplays]

thats really cool

[@RT-.]

You could write it with types with Luau and use darklua to remove those types

[@Hellscaped]

hello fellow switchcraft player

[@bruhrain]

I really love Lua, I normally work in C/C++ and use Luau or Lua 5.4 for my projects that require embedded languages like Lua to add extra functionality and provide my application with various custom api's which you can add in yourself by using the c api e.g. lua_pushcfunction - pushes a c function with the type int func(lua_State*, ...); Anyways, I really think that its cool that Roblox has done this but I'm pretty sure its not for use in the web however for more use in their Game engine for GUIs, correct me if im wrong though.

[@LoFiAxolotl]

it's hard to find any video game that doesn't have some cursed Lua in there... so good for Roblox for porting it... will be interesting to see in 10 years where all this Roblox stuff lead the then old enough programmers

[@harleyspeedthrust4013]

roblox has always had some flavor of lua powering their games. roblox has also been around for at least ten years, maybe 15 (I couldn't be bothered to check). so i bet that many of the kids who cut their teeth writing games and scripts for roblox 10 years ago are working in software today

[@dytra_io]

I think all js developers should learn lua

[@MichaelArinze-c4u]

Lua can be literally embeded into any place its crazy. I literally wrote code on a minecraft robot in a mod

[@honkhonk8009]

Yea seriously why isnt lua used more. I wish lua replaced python

[@MichaelArinze-c4u]

@@honkhonk8009 Lua has its range of problems I can't even lie It was my first language i learned and I barely use it anymore to this day

[@RobertoRenovato]

The best part of learning Lua is to make Pico-8 games. 😁

[@SaveThyPlanet]

I had pointed this problem how lua handles length in a PR to harpoon README fix.

[@petrusboniatus]

You can also embed scheme, with a similar size of Lua.

[@MarcelRobitaille]

micropython is definitely still a thing but I've only ever heard about it in the context of microcontrollers.

[@lwinklly]

YESSSSSSSSS REACT-LUA GETTING ATTENTION!!!!!!!!!!!!!!!!!!!!!!!!!

[@lwinklly]

Both repos' github stars have doubled/tripled *already*, I don't know what arc this is starting but the part of my brain that has been interested in react-lua since 2021 couldn't be more hyped

[@BenDol90]

That's why I love Nelua

[@krumbergify]

I hate that just like in QBasic any mispelled variables get a default value, nil. Instead of crashing and showing me the bug early the program continous and causes strange side effects :(. However I like Lua:s coroutines and how easy it is to embed it .

[@St3amPunk]

Yo dog, i heard you like Integrated development environments, so we downloaded an integrated development environment to program an integrated development environment so you can program an integrated development environment with my integrated development environment.

[@palharez]

Thanks for Brazil Mentioned in the end!

[@ajnart_]

Someone should make a course to teach programming in Roblox where you have to solve problems using code in the game. Would make an excellent class

[@mikec2845]

there's a Roblox game that does this, called lua learner or something. made by top developers on the platform

[@glockcodes]

this is crazy work chat

[@_Khrix]

Lua mentioned let's go Vai Brasil

[@ryan_the_dev]

Typescript for lua incoming.

[@jembulkezmaslem5214]

Well actually it already happened since roblox uses their own modified version of lua called luau. It has types. Can't escape typescript lol.

[@zzhabib1]

Already exists, roblox-ts is a TypeScript to lua compiler

[@RT-.]

@@zzhabib1 Yep and it's used in production by some very big games

[@hallo7053]

yeah but luau is different, they control the full stack unlike ts which is just a transpiler to javascript

[@MagnumCarta]

Thank God they didn't make Angular in Lua. If they did, that'd be a big "Oof"!

[@corvoworldbuilding]

LUA MENTIONED LET'S GOOOOOOOO!!!!!!

[@thingsiplay]

GO MENTIONED LET'S RUST

[@randerins]

​@@thingsiplaywhat

[@thingsiplay]

@@randerins yes

[@Kitsune_Dev]

I can’t get a job with 8 years of Lua experience

[@Sommyie]

2:06 Well that don't make no sense, partner.

[@KvapuJanjalia]

You forgot to mention that Roblox created their own dialect of Lua, named "Luau".

[@thingsiplay]

6:50 How is Luas error handling different from Pythons Try..Catch?

[@SilentFire08]

because you didnt have to use try catch :)

[@tranquangthang8897]

pcall?

[@isodoubIet]

@@tranquangthang8897 trivial to implement

[@isodoubIet]

@@tranquangthang8897 trivial to implement that in py

[@isodoubIet]

very easy to implement pcall in py

[@abliez]

roblox's luau fixes the thing with nil in a table

[@alminecrafteano]

We LOVE lua

[@KashTheKingYT]

Roblox has had Roact for a long time actually

[@sczoot6285]

It's not a "1 based indexing" difference it's indexing based off of an index rather than an offset

[@isodoubIet]

Stop repeating TJ's nonsense. An "index" doesn't start at 1. An index, in sane programming languages, starts at zero. The difference is not between "indexing" and "subscripting", because those are the exact same thing; the difference is between "indexing" and "counting". Tl;dr it _is_ 1-based indexing.

[@joeljohansson6097]

nothing preventing you from making a my_better_table module/abstraction in lua... i made my own switch and class "keywords" to get rid of all metatable handling for example

[@sczoot6285]

I had to write a PlayDate game in lua and had a great time towards the end

[@LaughingOrange]

Came to laugh at Roblox doing something stupid, ended up changing my mind on Lua as a language.

[@erentr7167]

Compiler steps lol TypeScript -> JavaScript -> LUA -> CPP -> Assembly

[@jorgamund07]

I haven't watched the video yet, but that's a banger of a title.

[@Frostbytedigital]

Shoulda picked solid

[@dealloc]

5:30 or you can embed a Lisp. But Lua is probably your best bet.

[@mrchickenrocket1]

What do you think of luau?

[@Gennys]

Prime the first question you asked you just completely sidestep the answer and just started talking about Lua instead of the first question you asked which was how good is JS to Lua as a transliteration step.

[@UNNIETKTJ]

So thats why the script doc/api is soo slow to load in my brownser

[@petermen9914]

What about C/C++ or Arduino for embedded systems? The are really popular. Just asking, probably I didn't get sth important here |^

[@UnidimensionalPropheticCatgirl]

Embedded scripting is what he is talking about, what you are talking about is embedded devices, those are like 99% done in C, occasionally some Ada or C++. Also arduino isn’t a language but a brand of MCUs, they use C with wiring HAL.

[@Max-wk7cg]

You also get to create World of Wacraft addons if you learn lua :)

[@Vitis-n2v]

So lua has quantum state it's both an array and a map

[@dipereira0123]

BRAZIL MENTIONED!! LETS GO!!🇧🇷🇧🇷

[@doriphor]

Can we replace JS with Lua everywhere?

[@eduardoADSL]

Lua and "go horse", two Brazilian contemporary inventions.

[@randerins]

....CAVALO.

[@sasuke2910]

A lot of justifying of Lua, but that's doesn't really strike me as the shocking thing about this. I guess Prime assumes that React on the Roblox frontend is a given.

[@jake-gs2gd]

It’s for the game engine and making game guis. Not for the site

[@aDaily1222]

What does "embedded systems" really mean? lol every one has a diff answer, i would like to know @ThePrimeTime 's definition

[@bennythetiger6052]

I think any system that is specific to a device that is not considered a general purpose computer could be called embedded

[@mage3690]

​@@bennythetiger6052I think prime's answer likely includes "device [or environment]" since he sometimes uses "embedded" to mean "embedded into a videogame". But yeah -- "specific to a device that is not considered a general purpose computer" is a pretty good definition, so long as you don't use "Turing machine" as your definition for "general purpose computer".

[@aDaily1222]

@@bennythetiger6052 i like that one.

[@bennythetiger6052]

@mage3690 I just mean a computer that wasn't made with a highly specific intention, like TVs for streaming videos, headphones for streaming audio, smart hubs for home or car controls, etc.

[@crooda3681]

2:15 bro it's just table, what's important with that problem 🙏

[@ninjalacoon]

Lua computercraft

[@pxkqd]

What I don't like about Lua is the split with Luajit. It's like python2 and 3. At least in javascript we know newest is better.

[@LtdJorge]

You mean the post Lua 5.1 stuff?

[@pxkqd]

@@LtdJorge yeah, there's a 5.4 but both luajit and luau which I are pretty popular are stuck in 5.1 I know you can just use any version and it's not so super different, but it still makes Lua code less portable. I haven't checked but is this react-lua and the other Roblox stuff 5.1, or Luau syntax? Can it be used in Luajit? Or in official Lua? 🤷🏻‍♂️

[@LtdJorge]

@@pxkqd I'm pretty sure the React thing is in Luau, since it's for Roblox UI.

[@mxruben81]

​@@pxkqdluau does have features from newer versions of lua, they're just really picky about what they add.

[@chavin-gx6ll]

is it just me or is your voice a tad bit different, if you mentioned this in another video or stream im sry i don't know lol. Well if you are under the weather I hope you feel better!

[@Cahnisama]

They need roact-table

[@Snipe_BLOX]

Why did I quote Roblox game developing for python and now web development ☠️

[@ncpeaksean4278]

Braaaaziillll 😂

[@ReedoTV]

Lua sounds cool. What country is it from?

[@GabrielLima-gz8zg]

Brazil!!! 🇧🇷

[@rockpie.iso.tar.bz2]

next up: QEMU ported to Lua(u)

[@HowManySmall]

lmfao i was the one who first found this in the roblox open source server

[@lwinklly]

graah why are you here

[@monad_tcp]

Metatables !

[@kodekata]

U mean php in Lua (react is bringing phpisms to js)

[@rich1051414]

In lua, it's not 'for x in iterator', it's 'for i,x in table'

[@tfiatd]

…aaand how do you read a table?

[@rich1051414]

@@tfiatd My point was that for loops in lua are kinda weird compared to most other languages.

[@ShadowKestrel]

i wonder how feasible it would be to have lua running natively in the browser

[@osmano807]

There's a browser with Lua instead of JS named Bussin Web X

[@ahdog8]

Not exactly "native", but a WASM Lua runtime could probably be made with relative ease. I searched and it seems like someone's already working on one

[@morji8664]

Its only for roblox?

[@nonono9700]

So tj can be a react dev now?

[@tokisuno]

why are you on lua 5.1.5?

[@mrroblick]

Roblox uses the Luau scripting language, not Lua.