Lil' Fun Langs

#1

Post by surprisetalk » Fri, Feb 20, 2026, 5:34 PM UTC

Lil' Fun Langs
taylor.town

Re: Lil' Fun Langs

#2

Post by mlajtos » Fri, Feb 20, 2026, 6:37 PM UTC

Fluent – 4K lines – including parser, interpreter, standard library, IDE, UI, docs, examples. Will grow though.

https://github.com/mlajtos/fluent/blob/main/client.tsx

Re: Lil' Fun Langs

#3

Post by surprisetalk » Fri, Feb 20, 2026, 6:58 PM UTC

mlajtos wrote: post #2

Fluent – 4K lines – including parser, interpreter, standard library, IDE, UI, docs, examples. Will grow though. https://github.com/mlajtos/fluent/blob/main/client.tsx

I'll add it! Thanks.

EDIT: Actually, it's not quite "ML-family" enough for this post. But it is a remarkably cool project! :)

Re: Lil' Fun Langs

#4

Post by nimbus-hn-test » Fri, Feb 20, 2026, 7:38 PM UTC

[dead]

Re: Lil' Fun Langs

#5

Post by dunham » Fri, Feb 20, 2026, 7:45 PM UTC

My little language Newt is 7 kloc. Dunno if it's worth including, it's mostly an exercise to learn how these things work and is not as polished as I'd like.

- Self-hosted

- Compiles to javascript

- Bidirectional typechecking with NbE (based on elaboration zoo)

- Dependent type checking

- type classes

- ADTs with dependent pattern matching

- TCO (trampoline for mutually tail recursive functions)

- Erasure of compile-time only values (0, ω quantities, but not linear)

- Web playground

- LSP (added this month)

- Syntax is similar to Agda / Idris / Haskell

https://github.com/dunhamsteve/newt

Re: Lil' Fun Langs

#6

Post by solomonb » Fri, Feb 20, 2026, 8:09 PM UTC

surprisetalk wrote: post #3

mlajtos wrote: post #2

Fluent – 4K lines – including parser, interpreter, standard library, IDE, UI, docs, examples. Will grow though. https://github.com/mlajtos/fluent/blob/main/client.tsx

I'll add it! Thanks. EDIT: Actually, it's not quite "ML-family" enough for this post. But it is a remarkably cool project! :)

If you're accepting additions here is a fun one some friends and I did as experiment at the Topos Institute: https://github.com/ToposInstitute/polytt

And here is a set of single file lambda calculus implementations with a variety of extensions: https://github.com/solomon-b/lambda-calculus-hs

`polytt` is kind of an ended experiment but that lambda calculus repo i plan to extend in the near future.

Re: Lil' Fun Langs

#7

Post by lachlan_gray » Fri, Feb 20, 2026, 9:12 PM UTC

Another crazy one is SectorLISP, 223 lines of asm

https://justine.lol/sectorlisp2/

Re: Lil' Fun Langs

#8

Post by ecto » Fri, Feb 20, 2026, 9:40 PM UTC

loon is a lisp! https://github.com/ecto/loon

  [type Shape
    [Circle Float]
    [Rect Float Float]]
  
  [fn area [s]
    [match s
      [Circle r]  => [* 3.14 r r]
      [Rect w h]  => [* w h]]]
  
  [area [Circle 5.0]]

Re: Lil' Fun Langs

#9

Post by grimgrin » Fri, Feb 20, 2026, 9:48 PM UTC

ecto wrote: post #8

loon is a lisp! https://github.com/ecto/loon [type Shape [Circle Float] [Rect Float Float]] [fn area [s] [match s [Circle r] => [* 3.14 r r] [Rect w h] => [* w h]]] [area [Circle 5.0]]

idk how I haven't crossed a lisp with square brackets but dang I am sorta stunned at how I've never even envisioned it? thanks

Re: Lil' Fun Langs

#10

Post by taolson » Fri, Feb 20, 2026, 10:50 PM UTC

dunham wrote: post #5

My little language Newt is 7 kloc. Dunno if it's worth including, it's mostly an exercise to learn how these things work and is not as polished as I'd like. - Self-hosted - Compiles to javascript - Bidirectional typechecking with NbE (based on elaboration zoo) - Dependent type checking - type classes - ADTs with dependent pattern matching - TCO (trampoline for mutually tail recursive functions) - Erasure of compile-t…

Either newt was already in the list, or it got added. We talked a bit about using our languages for AoC 2024 -- looks like you've been keeping busy working on it!