What do I think about Lua after shipping a project with 60k lines of code? • Hacker News Board

Re: What do I think about Lua after shipping a project with 60k lines of code?

#81

Post by shermantanktop » Fri, Apr 18, 2025, 3:31 PM UTC

kgeist wrote: post #51

mabster wrote: post #5

With dynamically typed languages I feel it's better to wait until you've tried to maintain the code for a while before you consider the languages effectiveness. I had to maintain a very large Lua codebase that has been active for several years. One big problem with Lua was how it will happily take more or less parameters to functions and continue to execute compared to something like Python where it is an error to pa…

>This meant when we update a function signature we would often incorrectly update call sites, etc. The same thing happened with our huge legacy PHP monolith, which was written before type hints were a thing. Developers were reluctant to refactor large chunks of code when the time came, because it was just too easy to introduce bugs - you couldn’t be confident about anything without manually digging through tons of co…

This is something I watch out for: teams which fear their own code and operate defensively, typically with cargo-cult practices that accumulate even though they themselves aren’t well understood.

Re: What do I think about Lua after shipping a project with 60k lines of code?

#82

Post by jerf » Fri, Apr 18, 2025, 3:33 PM UTC

lifthrasiir wrote: post #16

nine_k wrote: post #6

One big takeaway: a 60k LOC project in Lua is doable, and it will not crumble under its own weight. Surprisingly, LuaJIT is not mentioned even once. Luau is mentioned, Teal is mentioned, Fennel, not. (But Haskell is mentioned!) Little is told about the general code structure, likely because it's dictated by the (C++-based) game engine with Lua bindings. It would be interesting to see an analysis of a comparably large…

> it will not crumble under its own weight It is possible to make it not crumble under its own weight, right? I had my share of Lua nightmare with more than 100K lines of code back when I was a gamedev [1], and it seems that there are some requirements in order to remain sane with the growth. Thankfully there are now multiple working type checkers for Lua, unlike when I had to built my own. [1] https://news.ycombinat…

You can make anything, even assembler, not "crumble under its own weight" if you, the developer, bring enough discipline and care to it.

The main reason I like static languages and other such things is that after many decades of the programming community developing, since before I was born, we have not found very many best ways of "bringing enough discipline" to a codebase. It really all amounts to the same disciplines over and over. Check the types. Be sure guarantees are maintained. Document the input and output parameters. If there were dozens of very distinct and mutually-contradictory ways to impose this discipline, and there was no clear domination among those ways, then it might make sense for all of our languages to be loosey-goosey and not impose anything directly. But since we all generally find the same disciplines, we might as well pull those up to the language level and thereby enable them to be fully supported, and share the tooling among each other rather than expecting every junior dev to reinvent it from scratch... which they won't.

Re: What do I think about Lua after shipping a project with 60k lines of code?

#83

Post by gavmor » Fri, Apr 18, 2025, 3:45 PM UTC

nirav72 wrote: post #35

This is the second game I've found out recently that is written in Lua. The first one one being - Beyond All Reason.

Beyond All Reason is a SpringTA fork (hack? build?) like Zero-K? So the underlying engine isn't Lua, but higher level scripting is. I'm pretty sure this is fairly common, or was once.

Other games with Lua scripting: Roblox, Baldur's Gate, Civilization VI, Crysis, Factorio, World of Warcraft, Far Cry, Leadwerks, Friday Night Funkin', Foldit, Garry's Mod, Aquaria, Balanced Annihilation, Bitfighter, Bos Wars, Cataclysm, CivCity: Rome, Civilization: Beyond Earth, Company of Heroes, Cortex Command, Counter-Strike 2D, Crimson Steam Pirates, Dota 2, Dungeon Crawl: Stone Soup, Dungeons, Dungeons II, Dungeons III, Elven Legacy, Empire: Total War, Escape from Monkey Island, Eufloria, Exodus from the Earth, Angry Birds.

Re: What do I think about Lua after shipping a project with 60k lines of code?

#84

Post by jlarocco » Fri, Apr 18, 2025, 3:48 PM UTC

aomix wrote: post #72

mabster wrote: post #5

With dynamically typed languages I feel it's better to wait until you've tried to maintain the code for a while before you consider the languages effectiveness. I had to maintain a very large Lua codebase that has been active for several years. One big problem with Lua was how it will happily take more or less parameters to functions and continue to execute compared to something like Python where it is an error to pa…

I saw someone describe python as “stressful” for this reason and I couldn’t agree more. It’s difficult to have confidence in any change I make or review. I need to sit down and manually exercise codepaths because I don’t get the guarantees I crave from the language or tooling. While with the small amount of Rust code I’ve written lately I could yolo changes into production with no stress.

> I need to sit down and manually exercise codepaths

Isn't that exactly what unit tests are for?

Re: What do I think about Lua after shipping a project with 60k lines of code?

#85

Post by je42 » Fri, Apr 18, 2025, 3:48 PM UTC

aomix wrote: post #72

mabster wrote: post #5

With dynamically typed languages I feel it's better to wait until you've tried to maintain the code for a while before you consider the languages effectiveness. I had to maintain a very large Lua codebase that has been active for several years. One big problem with Lua was how it will happily take more or less parameters to functions and continue to execute compared to something like Python where it is an error to pa…

I saw someone describe python as “stressful” for this reason and I couldn’t agree more. It’s difficult to have confidence in any change I make or review. I need to sit down and manually exercise codepaths because I don’t get the guarantees I crave from the language or tooling. While with the small amount of Rust code I’ve written lately I could yolo changes into production with no stress.

When using dynamic languages, either minimize code dependencies / function calls and complexity or ensure high test coverage.

Re: What do I think about Lua after shipping a project with 60k lines of code?

#86

Post by [deleted] » Fri, Apr 18, 2025, 3:49 PM UTC

pnathan wrote: post #73

aomix wrote: post #72

Earlier quoted context omitted.

I saw someone describe python as “stressful” for this reason and I couldn’t agree more. It’s difficult to have confidence in any change I make or review. I need to sit down and manually exercise codepaths because I don’t get the guarantees I crave from the language or tooling. While with the small amount of Rust code I’ve written lately I could yolo changes into production with no stress.

Agreed. I had to work in a larger Python codebase after spending a few years with Go and Rust and the drop in logical confidence around the language was remarkable. I have, roughly, sworn off dynamic languages at this point. Although I have dreams of implementing a firm typed system over Common Lisp.

[deleted]

Re: What do I think about Lua after shipping a project with 60k lines of code?

#87

Post by je42 » Fri, Apr 18, 2025, 3:52 PM UTC

rahil627 wrote: post #44

nine_k wrote: post #6

One big takeaway: a 60k LOC project in Lua is doable, and it will not crumble under its own weight. Surprisingly, LuaJIT is not mentioned even once. Luau is mentioned, Teal is mentioned, Fennel, not. (But Haskell is mentioned!) Little is told about the general code structure, likely because it's dictated by the (C++-based) game engine with Lua bindings. It would be interesting to see an analysis of a comparably large…

60k? try Roblox’s 60bajillion!

Roblox introduced LuaU to get static typing

Re: What do I think about Lua after shipping a project with 60k lines of code?

#88

Post by airstrike » Fri, Apr 18, 2025, 3:55 PM UTC

jlarocco wrote: post #84

aomix wrote: post #72

Earlier quoted context omitted.

I saw someone describe python as “stressful” for this reason and I couldn’t agree more. It’s difficult to have confidence in any change I make or review. I need to sit down and manually exercise codepaths because I don’t get the guarantees I crave from the language or tooling. While with the small amount of Rust code I’ve written lately I could yolo changes into production with no stress.

> I need to sit down and manually exercise codepaths Isn't that exactly what unit tests are for?

Except now you're writing and maintaining twice the amount of code instead of relying on the compiler and/or type checker to help you catch those errors

Re: What do I think about Lua after shipping a project with 60k lines of code?

#89

Post by airstrike » Fri, Apr 18, 2025, 3:58 PM UTC

kragen wrote: post #61

Heh: > ...why Lua was designed this way. Dmitry told me that Lua was created at the Pontifical Catholic University of Rio de Janeiro and that it was acceptable for Pontifical Catholic Universities to design programming languages this way.

Reads tongue in cheek but also to be clear, as a PUC-Rio alum I can say there's no such thing as a collective "pontifical catholic universities" board that determines how programming languages behave or how students and faculty should go about their businesses in a software engineering class...

Re: What do I think about Lua after shipping a project with 60k lines of code?

#90

Post by pansa2 » Fri, Apr 18, 2025, 4:08 PM UTC

jlarocco wrote: post #84

aomix wrote: post #72

Earlier quoted context omitted.

I saw someone describe python as “stressful” for this reason and I couldn’t agree more. It’s difficult to have confidence in any change I make or review. I need to sit down and manually exercise codepaths because I don’t get the guarantees I crave from the language or tooling. While with the small amount of Rust code I’ve written lately I could yolo changes into production with no stress.

> I need to sit down and manually exercise codepaths Isn't that exactly what unit tests are for?

Yeah, that's a common argument for dynamic typing. You're writing tests anyway (right?), and those will catch type errors and many other kinds of error. Why bother with a separate level of checking just for type errors?

I personally believe it's a valid argument (others will disagree). IMO the main benefit of static types isn't for correctness (nor performance) - it's to force programmers to write a minimal level of documentation, and to support IDE features such as autocomplete and red underlines. Hence the popularity of Python type hints and TypeScript, which provide these features but don't fully prove correctness nor provide any performance benefit.