A Lisp in 99LOC(github.com)

108 pointsby shikaanhace 11 meses26 comments

https://github.com/Robert-van-Engelen/tinylisp

27 comments

eqvinoxhace 11 meses

Holy cow this is —structurally, not just expression— some of the worst C code I have ever seen, with the abuse of the 'double' type, 'T' cast that looks like a declaration, endian dependency, and strict aliasing violations galore… does this even work on a modern compiler? o.O

omoikanehace 11 meses

It does not, because there is a syntax error on line 81 (extra close parenthesis):

https://github.com/Robert-van-Engelen/tinylisp/blob/2d0fb35b...

Y_Yhace 11 meses

Brought to you by this marvellous commit with the message "update",

https://github.com/Robert-van-Engelen/tinylisp/commit/40c6c0...

f1shyhace 11 meses

Certainly not the worst I have seen, by far; but yes, not pretty. IMHO “Just for making it shorter“. I would very much prefer 200 lines of actually readable nice code.

sevensorhace 11 meses

For reading, I enjoyed fe, which was very clear: https://news.ycombinator.com/item?id=36239175

f1shyhace 11 meses

Yes! Exactly what I meant. 700 lines, but of code that can be understood, and looks clearly as C. Also btw, the general file structure, the documentation, I prefer fe any day of the week. Thanks for pointing that out, I will take a look at it.

OhMeadhbhhace 11 meses

Yeah. It's munged to fit in 99 lines.

eqvinoxhace 11 meses

That's besides my point, which is why I said "structure, not just expression".

It could've used a struct rather than wedging tags into a double's first byte and still be 99 lines.

fami-comhace 11 meses

That's a standard technique in interpreters. All non-toy Javascript engines use it, for example.

cardiffspacemanhace 11 meses

Nan-boxing is awesome.

Spivakhace 11 meses

If that's the trick you object to then you will be sad to hear that Ruby uses it.

messehace 11 meses

Surpringly readable though, despite all that, if you've ever implanted a language in similar constraints.

messehace 11 meses

*implemented.

Too late to edit now.

OhMeadhbhhace 11 meses

Previously:

* https://news.ycombinator.com/item?id=32100035

* https://news.ycombinator.com/item?id=32095655

and

* https://BI6.US/CO/N/20250420.HTML#/042402

lisperhace 11 meses

Lisp in ~100 lines of Python:

https://flownet.com/ron/l.py

ginkohace 11 meses

Can’t you just “import lisp”?

lisperhace 11 meses

Um, no?

    Python 3.11.6 (v3.11.6:8b6ee5ba3b, Oct  2 2023, 11:18:21) [Clang 13.0.0 (clang-1300.0.29.30)] on darwin
    Type "help", "copyright", "credits" or "license" for more information.
    >>> import lisp
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    ModuleNotFoundError: No module named 'lisp'

f1shyhace 11 meses

Or from the venerable: https://norvig.com/lispy.html

nivertechhace 11 meses

A better starting point:

https://github.com/Robert-van-Engelen/tinylisp/blob/main/tin...

jhbadgerhace 11 meses

It's interesting that he seems to have written this for a pocket computer, because there actually was a pocket computer of similar vintage that had LISP built in -- 1989's Casio AI-1000

https://pockemul.com/index.php/2020/04/27/pockemul-1-10-0-ne...

forgotpwd16hace 11 meses

>C code in this project is strongly Lisp-like in compact form

Kinda reminds me J-flavored Whitney's one-page J interpreter.

mark_l_watsonhace 11 meses

The commented longer program listing was fun to read.

coderatlargehace 11 meses

can it execute the y-combinator?

f1shyhace 11 meses

I’m pretty sure does not handle TCO… so probably not, unless with a huge stack.

gbaconhace 11 meses

See tinylisp-extras.c for TCO.

https://github.com/Robert-van-Engelen/tinylisp/blob/2d0fb35b...

spyrjahace 11 meses

It doesn't appear to, but you could always add this to the included common.lisp file:

  (define Y (lambda (f) (lambda args ((f (Y f)) . args))))

curtisszmaniahace 11 meses