fe: A tiny, embeddable language implemented in ANSI C

by sph • 3 years ago

177 106 3 years ago

I was wondering what the goal of the project is. The README is not very clear on it, but the implementation document [1] does state design goals:

- Small memory usage within a fixed-sized memory region — no mallocs

- Practical for small scripts (extension scripts, config files)

- Concise source — less than 1000 loc

- Portable ANSI C (Windows, Linux, DOS — 32 and 64bit)

- Simple and easy to understand source

- Simple and easy to use C API

[1] https://github.com/rxi/fe/blob/master/doc/impl.md

LeifCarrotson• 3 years ago

- Portable ANSI C (Windows, Linux, DOS — 32 and 64bit)

I skimmed through the source, and aside from reading a file from STDIN to a `static char buf[64000];`, nothing in this seems to use the POSIX API. With that buffer trimmed to an appropriate length, it appears it could run on a microcontroller, which is always a useful thing to have.

jhvkjhk• 3 years ago

The author developed some games. Maybe the goal of fe is to write game scripts.

frou_dh2• 3 years ago

Doesn't really count as language design if it's toy Lisp #9368. Language implementation exercise, yes.

zokier2• 3 years ago

Who is counting?

frou_dh2• 3 years ago

Well I counted 0 references to Lisp or Scheme in the documentation, so it seems to be presented as novel.

baq3• 3 years ago

Me, I’m counting!

kristianpaul• 3 years ago

Wondering how it compares to Lua

zokier2• 3 years ago

Almost two orders of magnitude smaller codebase.

ideasman42• 3 years ago

Are there any projects using this?

stevekemp2• 3 years ago

cel7 is a 60kb framework for making grid-based games limited to 4-bit color ASCII output. The framework is based around the fe programming language:

https://rxi.itch.io/cel7

There is a community edition which can be used, as the original is closed source:

https://github.com/kiedtl/cel7ce

There is also "aq", a small framework for making audio toys:

https://github.com/rxi/aq

stevefan1999• 3 years ago

Just another LISP clone...

tm2t• 3 years ago

Yes, and? What's wrong with that?

masukomi2• 3 years ago

nothing's wrong with another lisp clone.

the problem is with not being upfront about it. The problem is the implication that this is something new, that may solve some new problem in some new way.

Now, it MAY do something other lisp clones don't, but if it does there's zero indication of it in the readme.

jacknews8• 3 years ago

car? cdr? bye!

zeckalpha2• 3 years ago

What do you think HN is written in?

jacknews8• 3 years ago

lisp is great, I'm currently learning Janet, playing with fennel and clojure.

But a new 'lispish' should not replicate ancient historical 'accidents', IMHO, and in fact lisp itself should deprecate these names (and caar, caadr, caaaddr ... OMG).

first, rest, or head, tail, or whatever please.

incrudible• 3 years ago

Who cares what HN is written in? It could be written in anything. No, I do not buy the Blub programmer argument, either. Yes, maybe literal geniuses are attracted by exotic languages, but genius alone makes for poor business decisions.

sirsuki• 3 years ago

I once wrote a tiny DSL language. I used LISP (S-Expressions with parenthesis) because it semantically fit and made the parser much easier to write. I was laughed at and ridiculed by my peers. Everyone hated it that I had to attempt two other language styles just to compensate. I had a chuckle seeing fe syntax is LISP like and I was like “See? I’m not the only one.” Many just can’t give LISP and S-Expressions their due regard. Same for Reverse Polish Notation. I was born on the wrong planet.

drpixie• 3 years ago

I love RPN for calculating - I still regularly use a HP11C (Swiss Micros replica).

But I hate coding or reading prefix (list) or postfix (rpn, forth, etc) languages. Once wrote a substantial project is Postscript - works fine but note easy on the brain.

Guess it comes from just too much familiarity with infix notation!

packetlost3• 3 years ago

I personally find prefix and RP notations to be pretty easy to read, but writing is harder for me. I've introduced bugs into FORTH programs because I did a + b instead of a b + out of habit. I think both notations have their place and not everyone will be able to make the switch

nine_k4• 3 years ago

There are Lisp macros that allow writing infix arithmetics. Even fe is said to support macros.

lelanthran2• 3 years ago

No you weren't, many of us, like myself, have designed small languages over the years.

After a few of these, you stop designing syntax: you just skip the syntax and directly read ASTs instead of whatever syntax you wasted your time on.

My next language is going to be a FORTH of some type .

carapace• 3 years ago

I worked with Joy for some time and came to the conclusion that syntax is a MacGuffin.

packetlost3• 3 years ago

I don't think it's worth making a FORTH unless you plan to build an optimizing compiler better than what iForth, gForth, or VFX have done, open source and maintain it, or exclusively target microcontrollers. FORTH is a great "language" but the ecosystem is tiny and the tooling is pretty minimal.

baq3• 3 years ago

You’d be hailed as a genius if you replaced s-expressions with yaml.

cpeterso• 3 years ago

John McCarthy had the opposite experience: he originally planned to replace Lisp's S-expressions with a more ALGOL-like syntax called M-expressions, but other people liked S-expressions and he never got around to implementing M-expressions.

https://en.wikipedia.org/wiki/M-expression

rurban• 3 years ago

= for defun, really? why not set?

= really is for equality in lisp, not assignment

stefncb• 3 years ago

Why is it so strange that someone ignored a convention?

maleldil3• 3 years ago

Because it's a 50-year old convention, and there doesn't seem to be a compelling reason for ignoring it. The language then uses `is` for equality, including numbers.

It's just weird, especially given they're using old-fashioned car/cdr instead of head/tail.

sph2• 3 years ago

There is no mention of this being a Lisp anywhere in the name or README files.

You are mistaken in assuming that, since it has parens, then it must conform to being a Lisp.

JonChesterfield• 3 years ago

I read (= a b) as unification and slowly pieced together that it was probably assignment. Not as equality as the results of all the expressions starting = were discarded.

hayley-patton• 3 years ago

APL, ML and Pascal too. There is a story that Ken Iverson, the inventor of APL, was passing a terminal at which a Fortran programmer had just typed:

      I = I+1

Ken paused for a moment, muttered “no it doesn’t”, and passed on.

zogomoox• 3 years ago

When I see amazingly compact language implementations like this, the effect on me is not 'I want to use this language' but rather 'I should also write my own LISP'.

tjoff• 3 years ago

I misread it as 'I should write my own LSP [for that language]', which might be neat project too!

stevekemp2• 3 years ago

I wrote a lisp, a while back, and then later added an LSP for it.

Since lisp is so simple in terms of syntax what I really did was tab-completion, and info-on-hover, for the built-in functions like "car", "cdr", and the primitives I added as part of a more complex standard-library.

In my case I was writing in go and I found an LSP-server package which was trivial to use. So getting the integration with emacs, vim, etc, was really trivial:

https://github.com/tliron/glsp

ranger_danger• 3 years ago

Strange effect however I kinda felt it too. But alas `#include <setjmp.h>` here be dragons.

mananaysiempre• 3 years ago

Unless you want half your C logic to be error propagation, it’ll have to be <setjmp.h>, all its flaws notwithstanding. Manual unwinding can be done tastefully (see Tcl), but in the single-digit-KLOC weight class it’s not really a choice.

fsckboy• 3 years ago

while we're marvelling about how small and compact it is, then just replace them (with something uglier and less performant), it's not rocket science

bpierre• 3 years ago

Not to be confused with Fe: https://fe-lang.org/

yebyen• 3 years ago

There's an awful lot of languages with an .fe code file extension, aren't there:

https://ferite.sourceforge.net/

calibas• 3 years ago

Also not be confused with ferric oxide: https://www.rust-lang.org/

joeatwork• 3 years ago

If this project interests you but is a bit more minimal than you need, the Janet language is a slightly-less but still pretty lightweight embeddable Lisp with a strong library and community: https://janet-lang.org/

rychco• 3 years ago

I just started toying with Janet recently & so far it’s very pleasant

schemescape5• 3 years ago

Has anyone here switched from Common Lisp or Scheme/Racket to Janet? If so, what was good/bad about the switch? Or was it just different?

I recently started learning Common Lisp, and it’s been mostly great, but my two complaints are 1) memory usage and 2) deployment (copy source or distribute a relatively huge world image—and I haven’t found any way to get a fully static build without patches, even with ECL).

Janet could solve both of those, although I’d pay a performance penalty due to it being interpreted, and I assume there are a lot fewer libraries/tools. I really like the idea of a Lua-sized Lisp, but I’m not sure if I should jump ship from a traditional Lisp yet.

baq3• 3 years ago

I’ve never done basically any lisp except a toy project but this

distribute a relatively huge world image

in my understanding of the lisp world is actually a feature…?

nine_k4• 3 years ago

Janet is planned and built as an embeddable language; CL is not.

Lyngbakr• 3 years ago

Does Janet have something like Clojure's threading (->, ->>)?

tionis• 3 years ago

Yes it does: https://janet-lang.org/api/index.html#-%3E%3E

klibertp• 3 years ago

For a Lisp not to have threading macros, it would need not to have macros, period. Writing these is so trivially simple you can ask ChatGPT to do it and it would get it right on the first try.

On a related note: it would be an interesting read if someone tried tracing the threading macros to some origin point(s) in the past. There seem to be two main variations, Lisp's ->/->> and |> in many functional languages (Elixir, OCaml, Raku). The construct seems to have gotten popularized by Clojure and F#, but I don't think it was invented in either (maybe rediscovered).

It had to start at some point, somewhere, but I wasn't able to locate that point.

wsc981• 3 years ago

Maybe a little bit offtopic, but rxi also made a few Lua / LÖVE 2D libraries that I've been able to put to good use, namely shash [0], lume [1], json.lua [2] and classic [3].

He makes some nice stuff.

---

[0] https://github.com/rxi/shash

[1] https://github.com/rxi/lume

[2] https://github.com/rxi/json.lua

[3] https://github.com/rxi/classic

vitiral2• 3 years ago

cool a lisp clone. Good work.

Could macros be used to add structs? How much code would this require?

I don't feel like a language is real until you can associate data. It's literally the first thing I do when I start any software project that's not a five line script

Iwan-Zotow• 3 years ago

Femtolisp anyone? Use in Julia I believe

https://github.com/JeffBezanson/femtolisp

ComputerGuru• 3 years ago

Here is as good of a place as any to ask: does anyone know of an embeddable scripting language pretty much exactly like Lua but with more C-like syntax?

EDIT: the best alternatives I'd previously found were rhai (still niche and weak library) and sandboxed JS (heavier than I would like and the standard library is still poor).

avgcorrection• 3 years ago

I haven’t heard of that. Something that just compiles to Lua would probably be the easiest way to achieve that.

vitiral2• 3 years ago

Not exactly the requirements your asking but you might be interested in the language I'm writing

github.com/civboot/fngi

xlo• 3 years ago

Maybe AngelScript?

alwaysbeconsing• 3 years ago

Maybe Wren? It has classes and method syntax too but it's mostly C like: curly-braced blocks, operators are pretty much the same, slash and slash-asterisk comments, if/while/for with parens, ... Statements are not terminated by semicolons, though.

https://wren.io/syntax.html

schemescape5• 3 years ago

For JavaScript, did you look at QuickJS? I believe the binary size is in the same range as Lua.

The standard library isn’t terribly extensive, but I think it’s more comprehensive than Lua, no?

kortex• 3 years ago

Donnie: I made a new language
Therapist: New language, or LISP dialect?
Donnie: LISP again

Mostly a dig at the title. Jokes aside, I love how concise this is. Not sure how I feel about readability, too many inline if {} blocks for my liking, and a bit arcane. But I'm never not gonna upvote novel languages. Something about language creation delights me.

beeforpork• 3 years ago

There's also ulisp (for Arduino projects etc.): http://www.ulisp.com/

This is larger, because there are functions for accessing peripherals, and the core is more standard lispy with 'caadr' et.al., and it has a compacting GC, so images can be saved as a compact blob.

slmjkdbtl• 3 years ago

i always go to rxi if I want to read some good concise c code, every one is worth reading

fe: A tiny, embeddable language implemented in ANSI C

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