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
omoikane 2 days ago [-]
It does not, because there is a syntax error on line 81 (extra close parenthesis):
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.
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.
messe 2 days ago [-]
Surpringly readable though, despite all that, if you've ever implanted a language in similar constraints.
messe 2 days ago [-]
*implemented.
Too late to edit now.
OhMeadhbh 2 days ago [-]
Yeah. It's munged to fit in 99 lines.
eqvinox 2 days ago [-]
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-com 2 days ago [-]
That's a standard technique in interpreters. All non-toy Javascript engines use it, for example.
cardiffspaceman 2 days ago [-]
Nan-boxing is awesome.
Spivak 2 days ago [-]
If that's the trick you object to then you will be sad to hear that Ruby uses it.
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'
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://github.com/Robert-van-Engelen/tinylisp/blob/2d0fb35b...
https://github.com/Robert-van-Engelen/tinylisp/commit/40c6c0...
Too late to edit now.
It could've used a struct rather than wedging tags into a double's first byte and still be 99 lines.
* https://news.ycombinator.com/item?id=32100035
* https://news.ycombinator.com/item?id=32095655
and
* https://BI6.US/CO/N/20250420.HTML#/042402
https://flownet.com/ron/l.py
https://github.com/Robert-van-Engelen/tinylisp/blob/main/tin...
https://pockemul.com/index.php/2020/04/27/pockemul-1-10-0-ne...
Kinda reminds me J-flavored Whitney's one-page J interpreter.
https://github.com/Robert-van-Engelen/tinylisp/blob/2d0fb35b...