Pluto is a unique dialect of Lua with a focus on general-purpose programming

38 90s_dev 21 7/1/2025, 12:58:22 AM github.com ↗

Comments (21)

matusnovak · 14m ago
Is it possible to use Pluto alongside with a binding library such as Sol2[0]? I don't mind not being able to set type hints in the bindings to use in some IDE, I can create stubs for it manually.

[0]: https://github.com/ThePhD/sol2

yannis · 1h ago
Well written and well documented. I will be trying it out. One drawback that I see is the use of packages from LuaRocks might be an issue and one does not really want to cope with compilation issues. But Lua is a beautiful language in any form.
wavemode · 6h ago
Curious how this compares with Luau: https://luau.org
Rochus · 3h ago
Rochus · 3h ago
Interesting, apparently the source also includes a (modified) version of the PUC Lua VM. Why don't they just generate bytecode for the existing VM and leave it as is (unless the modified version somehow would significantly increase performance)? What changes were necessary to the original VM to implement the language?
90s_dev · 3h ago
Some features like break N and default function args seem to be incompatible with the vanilla lua vm.
Rochus · 11m ago
I think that would be achievable with plain PUC Lua bytecode; it's actually just a jump. The same for default function arguments; the VM doesn't actually care how many arguments the caller pushes on stack, and providing default values is easy to implement for the caller.
tzury · 4h ago
Well, this is a very poor design, one which makes me think what is the purpose of this project in the first place?

    for i = 1, 10 do -- Loop 1.
        for ii = 1, 5 do -- Loop 2.
            break 1 -- This will break from Loop 2.
            break 2 -- This will break from Loop 1.
        end
    end
https://pluto-lang.org/docs/New%20Features/Break%20Statement
gitaarik · 3h ago
Seems logical to me. 1 = break the current level, 2 = break 1 level up, 3 = break 2 levels up, etc.

If you would do it the other way around, and then if you would add another for loop around the others, the breaks will break. You wouldn't expect that if you're modifying this code without looking at the current breaks or knowing about the break behavior.

If you however move the break statements inside a new for loop, at the most inner level, it would seem obvious that you have to update the break numbers.

nextaccountic · 2h ago
Adding a label to each loop and breaking by label (like in Rust) feels better and more resistant to code changes
lifthrasiir · 1h ago
I don't particularly dislike that design, but Lua already supports a goto target label `::label::` so I think the following syntax would work better:

    ::outer:: for i = 1, 10 do
        ::inner:: for ii = 1, 5 do
            break inner
            break outer
        end
    end
raincole · 42m ago
That's a Lua dialect so I don't know what you expect ;)
philsnow · 3h ago
What's poor about it, the numbers in the example? Think of them as inner/outer instead of "1" and "2". Without this kind of break statement, what do you do when you want to exit the outer loop, something like this probably:

  local stop = false
  for i = 1, 10 do         -- outer loop
    if stop then break end
    for j = 1, 5 do        -- inner loop
      break                -- to break from inner loop
      stop = true; break   -- to break from outer loop
    end
  end
So this new feature fits with the general theme of pluto being a very-sugared lua.
aa-jv · 2h ago
This is just poor language design.

The reason one might find this cumbersome or problematic, is in the case of very large numbers of lines of code - sure, your example is visible and somewhat readable (arguable) in its current form - but tell me you won't have issues when the loop is 80 or 100 lines of code, and you need to add another inner loop as part of the development process.

Are you now going to go through and be sure all your breaks are numbered properly? Are you really, though?

Better, imho, would have been to introduce labels and "break <label>", but even that is going to cause more headaches than its worth.

Ultimately, one shouldn't write such horrid code anyway.

chirsz · 4h ago
I guess it is inspired by De Bruijn index[1].

[^1]: https://en.wikipedia.org/wiki/De_Bruijn_index

sweetgiorni · 4h ago
That's... interesting.
tzot · 36m ago
If the numeric argument to break is what you find interesting, then this is exactly the same construct as the shell's break argument:

https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V...

ModernMech · 4h ago

  "Pluto aspires to be a version of Lua with a larger feature-set, that is all. Pluto is not a Lua-killer, an attempted successor, or any of that. Many people (rightly so) love Lua precisely because of the design philosophy. And fundamentally, Pluto is a major deviation from Lua's design philosophy. Some may prefer this, some may not."
90s_dev · 9h ago
Basically a more convenient/intuitive Lua for JS/C/Java/C++ users, plus optional static typing. May in fact use this instead of Lua.
JdeBP · 17m ago
There's almost nothing in there that's like C or C++. But there's a definite influence of .NET and C♯ with things like null-coalescing, null-conditionals, and interpolated strings.
Imustaskforhelp · 5h ago
Yea. I am definitely trying this out too. It really has some new features changes that I wished lua had.