LjTools VS tl

I dug a little more and came across this tool which does seem to have the capability to view all LuaJIT Bytecode. https://github.com/rochus-keller/LjTools

> a large lua game code base, over 4000 files, 1.5 million lines of code

Interesting; how do you manage to keep consistency? Do you have special tools to e.g. detect inadvertent global variables? I once wrote a Smalltalk VM in Lua (https://github.com/rochus-keller/Smalltalk/blob/master/Inter...) which is a much smaller code base but even with this size I quickly would have lost track of e.g. scopes and names without tools I had to write myself (https://github.com/rochus-keller/LJTools).

Most of my languages have VM backends; see e.g. https://github.com/rochus-keller/Oberon; I implemented different backends generating LuaJIT bytecode; a year ago I switched to Mono which is based on ECMA-335; here is a discussion why I switched: https://github.com/rochus-keller/Oberon/releases/tag/IDEv0.9.0; I implemented utility libraries for both LuaJIT and CIL bytecode; see https://github.com/rochus-keller/LjTools/, https://github.com/rochus-keller/Pelib/ and https://github.com/rochus-keller/MonoTools/. I evaluated many VMs and think the mentioned ones are best suited. There were a lot of challenges with both technologies, what is to be expected, and too much to describe here.

LuaJIT is well suited as a backend/runtime environment for custom languages; I did it several times (see e.g. https://github.com/rochus-keller/Smalltalk, https://github.com/rochus-keller/Som/, https://github.com/rochus-keller/Oberon/). I also implemented a bit of infrastructure to ease the reuse: https://github.com/rochus-keller/LjTools. LuaJIT has some limitations though; if you require closures you have to know that the corresponding LuaJIT FNEW bytecode is not yet supported by the JIT, i.e. switches to the interpreter; as a work-around I implemented my own closures; LuaJIT also doesn't support multi-threading, but co-routines; and there is no debugger, and the infrastructure to implement one has limitations (i.e. performance is low when running to breakpoints). For most of my projects this was no issue. Recently I switched to CIL/Mono for my Oberon+ implementation which was a good move. But still I consider LuaJIT a good choice if you can cope with the mentioned limitations. The major advantage of LuaJIT is the small footprint and impressive performance for dynamic languages.

Implementing a VM is certainly interesting, but if you just need a fast backend you could generate LuaJIT bytecode (see e.g. https://github.com/rochus-keller/ljtools/ LuaJitComposer.h/cpp).

If you want to re-use LuaJIT as a backend, have e.g. a look at https://github.com/rochus-keller/ljtools

Recently I mostly use https://github.com/rochus-keller/LjTools#lua-parser-and-ide-features

it's based off MIR, does it have something to do with https://mlir.llvm.org/ ?

for typed lua, there is another effort https://github.com/teal-language/tl in addition to the mentioned typescript approach: https://github.com/andremm/typedlua

I had the pleasure of working with Lua 5.1 back in the late noughties. For me it's replaced Tcl whenever I want something I can configure above a C library. At the time I used it I found it quite nice but I'll also not forget the hours I wasted tracking down nil table corruptions which could have easily been caught by a type checker.

I had some hope that Luau https://luau-lang.org or Teal https://github.com/teal-language/tl would make things better but with the following example

    function foo(x: number): string

I wonder why the author doesn't use Teal [0] - a typed dialect of lua.

[O] https://github.com/teal-language/tl

Check out Teal

There is already https://github.com/teal-language/tl, which is typed Lua. I think fennel exists to serve a different niche-- personally I use it not for any type features; I just like the syntax better, and others may find certain features like the macro system useful.

There's also some languages made to compile straight to Lua: - MoonScript is the most popular Lua wrapper - it's built to be more Python-like, featuring indentation-based scopes, function calls without parentheses, lambda syntax, list comprehension, and much more. - Yuescript is a modern update to MoonScript that adds more features (I haven't used it myself, so I'm not entirely sure exactly how it differs from MS). - Teal is a version of Lua that adds static typing for better code standards.

Terra and Nelua are both very different in goals than Teal. Teal is literally gradual types integrated into Lua keeping as many of Lua's idioms as possible (to a fault[1]). Terra and Nelua are both very metaprogrammable systems programming languages. Nelua's goals are primarily to soften C's rough edges, comparable to something like Nim.

There's another one you missed in Pallene[2]. But again, it's goal was to optimize the stack sharing involved in using the C API. It also adds types though and maintains Lua idioms as much as possible.

[1]: https://github.com/teal-language/tl/discussions/339

[2]: https://github.com/pallene-lang/pallene