4 ms·

Lisp implemented in under 1K of JavaScript

• deleted 12y ago
  [deleted]
• guard-of-terra 12y ago
  Thank you for at least not writing another Brainfuck clone.
• mattdw 12y ago
  It's JSON lists as s-exps, which means (as I understand it) that the author doesn't need to implement parsing, only traversal and evaluation. (Which can essentially be a big-ass case statement.) ["def", "foo", 1] ["fn", "foo", ["a", "b"], […]] It's not the most attractive Lisp I've seen…
  • infogulch 12y ago
    So write a lisp parser, then dump the result into this. I like that they didn't include a parser in compacted code, such a parser wouldn't be very interesting.
    • zardeh 12y ago
      So, uhmm, def parse(s): return json.loads('['+re.sub('([")])\s*(["(])','\g<1>,\g<2>',re.sub('[^()\s]+','"\g<0>"',s)).replace('(','[').replace(')',']')+']') works for python, I'm assuming javascript has something equally small
      • infogulch 12y ago
        Yes, uninteresting, as I said. Lisp syntax is quite simple, so I would not expect it to be very difficult to make a regex to parse it. Btw, does that handle quoted strings, strings with syntax characters in them, and strings with escapes?
        • agumonkey 12y ago
          And dotted pairs ? I had a super cute sexp parser in PHP, until I started handling sexp fully.
          • gps408 12y ago
            Would dotted pair notation make sense for this lisp where lists are arrays, not linked cons cells?
            • agumonkey 12y ago
              IMHO, yes, binary building blocks matter a lot in lisp philosophy, whether or not they're built on javascript arrays.
              • gps408 12y ago
                Thanks for responding, man. That's my point though. There is no cons building block in this lisp. I don't think (1 2 . 3) can be represented in it so having the notation for it makes no sense.
• andrewchambers 12y ago
  This person wrote a lisp in 1K lines of C (not bytes :)), the cool thing is that also includes a copying garbage collector. https://github.com/rui314/minilisp https://github.com/rui314/minilisp
  • rrmm 12y ago
    IMO, the garbage collection (along with optimization) is the most interesting part of implementing a lisp.
  • mrottenkolber 12y ago
    I wrote a minimal Lisp compiler (targeting C) when I was a bit younger. :> My GC was just a really bad reference counting implementation though. I dare you to make fun of my "hash function". Hehe. https://github.com/eugeneia/microlisp https://github.com/eugeneia/microlisp
    • rrmm 12y ago
      Your hash function is fast! So it's got that going for it.
      • PhantomGremlin 12y ago
        I had to go look. Not hard to find. I'll just say this, back in the prehistoric 1970s, a '%' operation was eschewed, because it wasn't fast (relatively speaking)!!! It often was used anyway, because it's very effective considering its simplicity.
• PinnBrain 12y ago
  So much effort to go under 1K (in the era of 128GiB fingernail chips), with this .gitignore: node_modules -uglify -crush -regpack
• TazeTSchnitzel 12y ago
  I wrote a minimal Lisp for PHP in about an hour: https://gist.github.com/TazeTSchnitzel/44720ea3aec64a9e330a https://gist.github.com/TazeTSchnitzel/44720ea3aec64a9e330a