Tuples: {number, string}
Arrays: {number}
How does it disambiguate it? Are single-element tuples just never used in practice? To be fair, maybe the only time I've had to use them in TypeScript is via Parameters
Teal – A statically-typed dialect of Lua
11–20 of 176 posts
Re: Teal – A statically-typed dialect of Lua
#12I'm so relieved to see more types being added to good languages. So Teal is to Lua as TypeScript is to JavaScript. Which means it automatically plays well with any Lua environment. Unlike luau and nelua which are also statically typed but have their own runtimes. What version of Lua does it use? Lua gets new versions every few years so I don't know why so many impls don't continuously upgrade to the latest version.
Lua is a good language. It's like C, if C were a scripting language. It's got an awesome C API. It's fast, lightweight, and embeddable. It's more performant than Python. It's a staple in video game scripting.
I don't think it's a good language, and I hate it. I've made thousands of the same mistakes with it—typing . instead of :. There's a reason Lua has a smaller audience than assembly.
Re: Teal – A statically-typed dialect of Lua
#13Oh, clever name. Typed Lua → TL → "Tee Ell" → Teal And the extension is .tl
Off-topic comment, but as an ESL speaker I just this week randomly learned that teal the color is named after the duck species Anas crecca , called (edit: common or Eurasian) teal in English.
I'm one of today's lucky 10_000 apparently! Only learned that just now.
Re: Teal – A statically-typed dialect of Lua
#14Is it implemented as a compiler, tl, which compiles .tl source code into .lua files? Who knows
Re: Teal – A statically-typed dialect of Lua
#15Has anyone used this? Any reviews? Based on the Github issues, the type system seems to have some holes in it, but it's not obvious how bad is it in real world.
Re: Teal – A statically-typed dialect of Lua
#16I've been diving into Lua (a little late to this party, but turns out it's a perfect language to rewrite some commandline scripts I had that were getting unwieldy in Bash, especially with LLM assistance!) and it's really something of an eye-opener.
LuaJITted Lua code runs at 80% (on average, sometimes faster!) of the compiled C version of the same algorithm, typically. Lua is embedded in a surprisingly massive number of products: https://en.wikipedia.org/wiki/List_of_applications_using_Lua The startup time of a script is in nanoseconds. An "echo" written in Lua runs faster than the native echo implementation.
The only warts so far are 1-based indexing (you get used to it), and the fact that LuaJIT is stuck at Lua 5.1 while Lua itself is up to 5.3 or 5.4 and has added some niceties... with Lua proper running slower. And no real standard library to speak of (although some would argue that's a feature; there are a few options and different flavors out there if that's what you need, though- Such as functional-flavored ones...)
Anyway, there's nothing else like it out there. Especially with its relative simplicity.
There are also some neat languages that compile to (transpile to?) Lua, and deserve more attention, such as YueScript https://yuescript.org/, which is a still actively-updated enhanced dialect of MoonScript https://moonscript.org/ (described as "Coffeescript for Lua", although it hasn't been updated in 10 years) although neither of these are typed. HOWEVER... there IS this: TypescriptToLua https://typescripttolua.github.io/, which takes advantage of ALL the existing TypeScript tooling, it just outputs Lua instead of JS!
Re: Teal – A statically-typed dialect of Lua
#17Earlier quoted context omitted.
Lua is a good language. It's like C, if C were a scripting language. It's got an awesome C API. It's fast, lightweight, and embeddable. It's more performant than Python. It's a staple in video game scripting.
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…
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.
Re: Teal – A statically-typed dialect of Lua
#18Earlier quoted context omitted.
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…
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.
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.
Re: Teal – A statically-typed dialect of Lua
#19Earlier quoted context omitted.
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.
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.
> 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.)
Re: Teal – A statically-typed dialect of Lua
#20> Teal is a statically-typed dialect of Lua.
I was expecting Teal to be "Lua + type annotations", similar to Mypy. However from a quick look it does indeed seem to be a "dialect" in its own right. Teal is Lua-like and compiles to Lua, but there's more to it than just static types. Perhaps it's more similar to TypeScript?
For example, Teal replaces Lua's tables - the language's signature single, highly-flexible data structure - with separate arrays, tuples, maps, records and interfaces. It changes the variable scoping rules and even adds macro expressions.
Teal therefore seems substantially more complex than Lua. The author recognizes this in the conclusion to a recent presentation [0]: Lua is "small and simple", maybe Teal is "something else"? Lua is for "scripting", maybe Teal is better suited to "applications/libraries"?