Feature Request: luau support

[Ughuuu]

Luau support would be nice.

While it doesn't support latest version of lua (5.4), and it is missing some things that need reimplementing:

• eg. require keyword, though there is in the lib an implementation of require

It excels at sandboxing, also has optional JIT for faster code execution (on platforms that support it), as well as support for typechecking.

[gilzoide]

Hey @Ughuuu, thanks for the request.

Well, sure, would be nice. I'm working LuaJIT support right now along with PUC-Rio Lua, haven't really considered any other runtimes, although I know plenty of them exist out there. We could also support Moonscript and Pluto and whatnot.

Not sure if those runtimes should live all in the same package or if they should be forks. LuaJIT support is already giving some headache, although mostly in the build side of things (I'm almost there, but Windows/MSVC is driving me nuts).

[Ughuuu]

O boi, yeah, making build work with luajit is not trivial. Last time i set it up i gave up and used vcpkg(i was doing with cmake). I'm not sure if there is someone doing scons and building luajit or not.
Afaik though, luajit is api compatible with lua. So just building statically luajit and then linking at compile time with it should do the trick. If you can even find a prebuilt version would be best for this use case. Or you can do with dll. How do you think of doing selecting of lua version?(if they were dlls, you could just have users use the dll they want, and have the main lua gdextension dll load the dlls in order(eg first it tries to load lua.dll, then liajit.dll, etc)). However, this would be vulnerable to a certain type of attack, by infecting the dll.
Having all of them statically linked could also prove difficult, bc of function collisions.
Only way is to distribute multiple versions of it.

[gilzoide]

I'm not sure if there is someone doing scons and building luajit or not.

I was able to build LuaJIT from SCons using its own Makefile (invoking make), but on Windows I'm trying to use MSVC and the msvcbuild.bat script, which is the only thing that is giving me trouble when linking into the GDExtension DLL (maybe it's C vs C++ problem in MSVC, idk). But I'll fix this later in a Windows machine (I usually work on macOS, so I was testing directly in GitHub Actions). Eventually it will work =D

How do you think of doing selecting of lua version?

My idea is to distribute separate versions of the addon, one for each Lua runtime. Luau would be another separate one.

[Kevadroz]

We could also support Moonscript and Pluto and whatnot.

May I suggest also supporting YueScript?

Not sure if those runtimes should live all in the same package or if they should be forks.

Also I think that languages like Moonscript and YueScript that compile to lua should just be included in any version that can support the languages. (For example those two should work just fine in PUC lua and luajit, and should work in Pluto in compatibility mode).

[always4ever11]

Luau would be nice for sandboxing (it has support for CPU and memory sandboxing, I don't think this is currently present in this extension)