undefined | Better HN

0 points90s_dev10mo ago0 comments

It's nothing like C, and that's so much of its charm.

Semantically, Lua is almost identical to the core of JavaScript. Metatables are a genius alternative to prototype chains.

Lua's syntax is beautifully simple and unambiguous, but at the cost of being moderately inconvenient in 2025 unfortunately. It could benefit from an ESNext-style renewal.

I get why they made the C API that way, but in practice it's very easy to get wrong.

I'm not sure how fast vanilla Lua is today compared to similar languages. I think LuaJIT (and Luau?) are most often used when performance is needed.

0 comments

isr10mo ago

FYI, for those who may not be aware, moonscript is the "coffeescript" for lua. It has been in production use for quite a while (the author of moonscript also created itch.io, using ... moonscript).

yuescript, from the dora-ssr game engine dev, is essentially moonscript-2.0

And of course, if you want to treat lua as the scheme-like it really is (deep down), then ... fennel.

Lots of choices. They all compile to straightforward lua, are very easy to incorporate (you can even compile at runtime, if you wish), and all employ full lua semantics, meaning zero runtime overhead

EDIT: and the curse of not reading fully ahead strikes again (doh!). Someone else has made the same points below ...

3036e410mo ago

If Teal is the TypeScript of Lua, Fennel is the ClojureScript. Except Fennel is fully implemented in Lua itself and it transpiles (usually) to very simple, plain Lua code without much (if any) overhead and with no run-time library other than what is in Lua itself.

https://fennel-lang.org/

xigoi10mo ago

The JavaScript equivalent of Fennel is Sibilant: https://sibilant.org/

growlNark10mo ago

Sure, if you compare via semantics Lua and Javascript make sense to liken. But in terms of complexity, Lua is far more like C. There's no unfucking all the horrible decisions baked into javascript and I wouldn't touch it with a ninety-foot pole, but Lua still has some hope.

90s_devOP10mo ago

Every language has warts. Even Lua.

Like another commenter said, using . instead of : is maybe the most common mistake, too easy to make. And Lua offers no help preventing or checking it.

TypeScript is a great language. So is Lua. So is C.

When used carefully to avoid their warts. Learning how to do that for any language takes time and practice though.

growlNark10mo ago

> Every language has warts.

Yea, and then there's javascript (or typescript if you prefer), the C++ of scripting languages. It's sometimes difficult to see any value through the warts. (Unless you're paid to, of course.)

1 more reply

SkiFire1310mo ago

To be fair Lua also made some bad decisions, though maybe not as bad as javascript:

- tables being used for both objects and arrays can create a lot of confusion, especially when you have some integer keys, but not all, and especially when they are not consecutive or one of them is 0 - indexes start at 1 - assigning nil deinitializes variables/entries instead of assigning the value `nil` (this becomes especially bad if you mistakingly try to use nil as a value in an array/table) - nil and false are falsy, but not 0, which instead is truthy

growlNark10mo ago

No disagreement here; I also fundamentally question the cardinal indexing and conflation between table and array. But it's at least internally consistent and certainly makes more sense than mandatorily indexing arrays with floating point.

ufo10mo ago

Tables being dual purpose is fine. The real problem is that assigning nil deletes the table field. Unfortunately, fixing that now would cause Python3 levels of breakage.

1 more reply

xigoi10mo ago

You’re using C as an example of a language that is easy to understand?

spookie10mo ago

C is indeed simple.

2 more replies

nmz10mo ago

> Lua's syntax is beautifully simple and unambiguous

    local print = print
    ("hello"):format()

    local foo = func
    ("args to func"):itreturnedatable("!")

90s_devOP10mo ago

Well of course you can trick people who aren't familiar with its syntax. But people who are see that this is

    local print = print("hello"):format()

    local foo = func("args to func"):itreturnedatable("!")

And I'm sure they can guess that that does.

nmz10mo ago

I didn't trick anybody, this was a pitfall that was patched in 5.2

j / k navigate · click thread line to collapse

0 comments

isr10mo ago

FYI, for those who may not be aware, moonscript is the "coffeescript" for lua. It has been in production use for quite a while (the author of moonscript also created itch.io, using ... moonscript).

yuescript, from the dora-ssr game engine dev, is essentially moonscript-2.0

And of course, if you want to treat lua as the scheme-like it really is (deep down), then ... fennel.

Lots of choices. They all compile to straightforward lua, are very easy to incorporate (you can even compile at runtime, if you wish), and all employ full lua semantics, meaning zero runtime overhead

EDIT: and the curse of not reading fully ahead strikes again (doh!). Someone else has made the same points below ...

3036e410mo ago

https://fennel-lang.org/

xigoi10mo ago

The JavaScript equivalent of Fennel is Sibilant: https://sibilant.org/

growlNark10mo ago

90s_devOP10mo ago

Every language has warts. Even Lua.

Like another commenter said, using . instead of : is maybe the most common mistake, too easy to make. And Lua offers no help preventing or checking it.

TypeScript is a great language. So is Lua. So is C.

When used carefully to avoid their warts. Learning how to do that for any language takes time and practice though.

growlNark10mo ago

> Every language has warts.

Yea, and then there's javascript (or typescript if you prefer), the C++ of scripting languages. It's sometimes difficult to see any value through the warts. (Unless you're paid to, of course.)

1 more reply

SkiFire1310mo ago

To be fair Lua also made some bad decisions, though maybe not as bad as javascript:

growlNark10mo ago

ufo10mo ago

Tables being dual purpose is fine. The real problem is that assigning nil deletes the table field. Unfortunately, fixing that now would cause Python3 levels of breakage.

1 more reply

xigoi10mo ago

You’re using C as an example of a language that is easy to understand?

spookie10mo ago

C is indeed simple.

2 more replies

nmz10mo ago

> Lua's syntax is beautifully simple and unambiguous

    local print = print
    ("hello"):format()

    local foo = func
    ("args to func"):itreturnedatable("!")

90s_devOP10mo ago

Well of course you can trick people who aren't familiar with its syntax. But people who are see that this is

    local print = print("hello"):format()

    local foo = func("args to func"):itreturnedatable("!")

And I'm sure they can guess that that does.

nmz10mo ago

I didn't trick anybody, this was a pitfall that was patched in 5.2

j / k navigate · click thread line to collapse