Experience has shown that having a map as your only data structure is definitely a mistake. It's much better to support real arrays too. I doubt it would have made the implementation significantly more complex either (maybe even simpler for luajit).
this post was submitted on 12 Feb 2026
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i think the most interesting design detail of lua tables is just glossed over as "nil-holes" in this article. namely, that nil values do not exist. there is no table.delete(key) method, you just zero out the value and the key stops existing. the same thing is true for any variable, if you set it to nil it ceases to be. i find that implementation fascinating.
Except it's ass if you want to do non-destructive data processing of arbitrary structures and your input and output might have null as a value. You can't just know about fields a, b, and c of the table and leave everything else as it is, you need to know the whole structure and make sure you write null in the output for fields that have nil in them.
Or, more realistically, use libraries that implement null as custom user data.
Iirc Roberto Ierusalimschy even considered introducing a null value in one of the recent versions, of course confusingly named ‘undefined’ — but changed his mind. Perhaps it's for the better than to have such a backwards name for it.
To my knowledge, Lisps like Emacs Lisp implement this better: trying to get a value for a nonexistent key will get you nil, but you can still retrieve the list of all keys, including ones that are set to nil.
yeah that's probably when you should drop down to C.
Eh, dkjson implements null as an object with a metatable function that encodes it back as "null". Hopefully it's considered equal to itself in comparisons.
Dkjson is fast enough for most scripting purposes. OTOH cjson's userdata null is supported by some other libraries that deal with data structures.
Of course, there's a problem then that various libs may have their own nulls, not equal to each other. There's even a lib that tries to marry some of them.
Such a strange website. Pretty decent content, but just lying around as HTML/js/css files without a coherent layout to tie them all together? Reminds me of good ol' internet.
Yes, I like it. It makes only one (big) mistake: a horizontal table-of-contents. Nobody does that. You can put it on the left, or above the text, but... not like that.
wdym coherent layout? this thing looks more coherent than any reactwebbloatapp i have seen
it is also very mobile friendly, no lag while scrolling because react is being the bloated garbage it is
I mean overall website, not the page itself. The page is super, but if you fiddle with the url a bit, the site has more nice content. But each page is different and seemingly don’t connect from other pages.
Good HTML is coherent by itself. Depends on if the html is good or not.