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.

I assume they did that for performance reasons, because removing entries is slow probably? From user perspective, it would have made it more sense to remove the key instead defining it as nil and then expecting the user to handle the nil. The key does not stop existing, right? I don't program in Lua.

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'm guessing the author didn't want to mess with a framework every time they post, with different page layouts they might've evolved over the years. Though the absence of site-wide navigation is still baffling.

Good HTML is coherent by itself. Depends on if the html is good or not.

Idk, PHP chugs on splendidly with arrays that combine both arrays and maps. I regret to say that PHP is considerably faster than some better languages like Python and Ruby, and arrays are the workhorse structure there.

(Like, PHP's approach to FastCGI is that the script's runtime is destroyed after every request and then started anew for the next one, and it still outperforms Python's always-on approach. Of mainstream languages, only Node can compete.)